diff --git a/.claude/CLAUDE.md b/.claude/CLAUDE.md
index e08a75b8e2..801b84de36 100644
--- a/.claude/CLAUDE.md
+++ b/.claude/CLAUDE.md
@@ -77,6 +77,14 @@ Multiple service providers for optional features (auto-discovered via composer.j
 
 Tests use `Tests\Utils\` namespace for test fixtures (Models, Queries, Mutations, etc.).
 
+### GraphQL string style in tests
+
+- Always annotate GraphQL literals with `/** @lang GraphQL */`.
+- Default to nowdoc: `<<<'GRAPHQL'`.
+- Use heredoc: `<<<GRAPHQL` only if interpolation is required.
+- Avoid quoted multiline GraphQL strings.
+- Preserve intentional indentation/whitespace in schema and assertion-sensitive tests.
+
 ## Code Style
 
 - PHPStan level 8
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 180b8e323e..d6937117e2 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -128,6 +128,16 @@ $user = User::create([
 ]);
 ```
 
+### GraphQL strings in tests
+
+Use a consistent representation for GraphQL literals in tests:
+
+- Use `/** @lang GraphQL */` before GraphQL string literals.
+- Use nowdoc (`<<<'GRAPHQL'`) for static GraphQL content.
+- Use heredoc (`<<<GRAPHQL`) only when interpolation is required.
+- Prefer nowdoc/heredoc over quoted multiline strings.
+- For schema/assertion cases where whitespace matters, keep indentation deliberate and stable.
+
 ## Working with proto files
 
 Lighthouse uses [protobuf](https://developers.google.com/protocol-buffers) files for [federated tracing](src/Tracing/FederatedTracing/reports.proto).
diff --git a/tests/Console/UnionDirective.php b/tests/Console/UnionDirective.php
index 7d10e23456..66cc59c63d 100644
--- a/tests/Console/UnionDirective.php
+++ b/tests/Console/UnionDirective.php
@@ -10,10 +10,10 @@ final class UnionDirective extends BaseDirective implements Directive
     public static function definition(): string
     {
         return /** @lang GraphQL */ <<<'GRAPHQL'
-"""
-Some other definition then the original.
-"""
-directive @union on UNION
-GRAPHQL;
+        """
+        Some other definition then the original.
+        """
+        directive @union on UNION
+        GRAPHQL;
     }
 }
diff --git a/tests/Console/ValidateSchemaCommandTest.php b/tests/Console/ValidateSchemaCommandTest.php
index f119a397af..a5f0968800 100644
--- a/tests/Console/ValidateSchemaCommandTest.php
+++ b/tests/Console/ValidateSchemaCommandTest.php
@@ -10,13 +10,13 @@ final class ValidateSchemaCommandTest extends TestCase
 {
     public function testValidatesCorrectSchema(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 arg: ID @eq
             ): ID @guard
         }
-        ';
+        GRAPHQL;
         $tester = $this->commandTester(new ValidateSchemaCommand());
         $tester->execute([]);
 
@@ -25,11 +25,11 @@ public function testValidatesCorrectSchema(): void
 
     public function testFailsValidationUnknownDirective(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @unknown
         }
-        ';
+        GRAPHQL;
         $tester = $this->commandTester(new ValidateSchemaCommand());
 
         $this->expectException(DirectiveException::class);
@@ -42,11 +42,11 @@ public function testFailsValidationDirectiveInWrongLocation(): void
         $this->markTestSkipped('This validation needs to be in the upstream webonyx/graphql-php validation');
 
         // @phpstan-ignore-next-line https://github.com/phpstan/phpstan-phpunit/issues/52
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query @field {
             foo: ID @eq
         }
-        ';
+        GRAPHQL;
         $tester = $this->commandTester(new ValidateSchemaCommand());
         $tester->execute([]);
 
diff --git a/tests/Integration/Async/AsyncDirectiveTest.php b/tests/Integration/Async/AsyncDirectiveTest.php
index bd7a931f75..ec914bc603 100644
--- a/tests/Integration/Async/AsyncDirectiveTest.php
+++ b/tests/Integration/Async/AsyncDirectiveTest.php
@@ -16,18 +16,18 @@ public function testDispatchesMutation(): void
     {
         $this->mockResolver(static fn (mixed $root, array $args, GraphQLContext $context, ResolveInfo $resolveInfo) => null);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             fooAsync: Boolean! @mock @async
         }
-        ';
+        GRAPHQL;
 
         $queue = Queue::fake();
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             fooAsync
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'fooAsync' => true,
             ],
@@ -48,18 +48,18 @@ public function testDispatchesMutationOnCustomQueue(): void
     {
         $this->mockResolver(static fn (mixed $root, array $args, GraphQLContext $context, ResolveInfo $resolveInfo) => null);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             fooAsync: Boolean! @mock @async(queue: "custom")
         }
-        ';
+        GRAPHQL;
 
         $queue = Queue::fake();
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             fooAsync
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'fooAsync' => true,
             ],
@@ -82,10 +82,10 @@ public function testOnlyOnMutations(): void
         $this->expectExceptionObject(new DefinitionException(
             'The @async directive must only be used on root mutation fields, found it on Query.foo.',
         ));
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Boolean! @async
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Auth/CanDirectiveDBTest.php b/tests/Integration/Auth/CanDirectiveDBTest.php
index b2924feb9b..8a1af82520 100644
--- a/tests/Integration/Auth/CanDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanDirectiveDBTest.php
@@ -25,7 +25,7 @@ public function testQueriesForSpecificModel(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID @whereKey): User
                 @can(ability: "view", find: "id")
@@ -35,15 +35,15 @@ public function testQueriesForSpecificModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->getKey(),
         ])->assertJson([
             'data' => [
@@ -64,7 +64,7 @@ public function testFailsToFindSpecificModel(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID @whereKey): User
                 @can(ability: "view", find: "id")
@@ -74,15 +74,15 @@ public function testFailsToFindSpecificModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -104,7 +104,7 @@ public function testThrowsCustomExceptionWhenFailsToFindModel(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID @whereKey): User
                 @can(ability: "view", find: "id")
@@ -114,18 +114,18 @@ public function testThrowsCustomExceptionWhenFailsToFindModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $this->rethrowGraphQLErrors();
 
         try {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: "not-present") {
                     name
                 }
             }
-            ');
+            GRAPHQL);
         } catch (Error $error) {
             $previous = $error->getPrevious();
 
@@ -142,7 +142,7 @@ public function testFailsToFindSpecificModelWithFindOrFailFalse(): void
 
         $this->mockResolver(null);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID @whereKey): User
                 @can(ability: "view", find: "id", findOrFail: false)
@@ -152,15 +152,15 @@ public function testFailsToFindSpecificModelWithFindOrFailFalse(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => null,
             ],
@@ -173,7 +173,7 @@ public function testThrowsIfFindValueIsNotGiven(): void
         $user->name = UserPolicy::ADMIN;
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID): User
                 @can(ability: "view", find: "some.path")
@@ -183,15 +183,15 @@ public function testThrowsIfFindValueIsNotGiven(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLError(CanDirective::missingKeyToFindModel('some.path'));
+        GRAPHQL)->assertGraphQLError(CanDirective::missingKeyToFindModel('some.path'));
     }
 
     public function testFindUsingNestedInputWithDotNotation(): void
@@ -200,7 +200,7 @@ public function testFindUsingNestedInputWithDotNotation(): void
         $this->assertInstanceOf(User::class, $user);
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(input: FindUserInput): User
                 @can(ability: "view", find: "input.id")
@@ -214,9 +214,9 @@ public function testFindUsingNestedInputWithDotNotation(): void
         input FindUserInput {
           id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(input: {
               id: $id
@@ -224,7 +224,7 @@ public function testFindUsingNestedInputWithDotNotation(): void
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -253,7 +253,7 @@ public function testThrowsIfNotAuthorized(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             post(foo: ID! @whereKey): Post
                 @can(ability: "view", find: "foo")
@@ -263,15 +263,15 @@ public function testThrowsIfNotAuthorized(): void
         type Post {
             title: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($foo: ID!) {
             post(foo: $foo) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'foo' => $post->id,
         ])->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
     }
@@ -292,7 +292,7 @@ public function testHandleMultipleModels(): void
         $postB->user()->associate($admin);
         $postB->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             deletePosts(ids: [ID!]! @whereKey): [Post!]!
                 @can(ability: "delete", find: "ids")
@@ -302,15 +302,15 @@ public function testHandleMultipleModels(): void
         type Post {
             title: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($ids: [ID!]!) {
             deletePosts(ids: $ids) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'ids' => [$postA->id, $postB->id],
         ])->assertJson([
             'data' => [
@@ -336,7 +336,7 @@ public function testWorksWithSoftDeletes(): void
         $this->assertInstanceOf(Task::class, $task);
         $task->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             task(id: ID! @whereKey): Task
                 @can(ability: "adminOnly", find: "id")
@@ -347,15 +347,15 @@ public function testWorksWithSoftDeletes(): void
         type Task {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id, trashed: WITH) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertJson([
             'data' => [
@@ -375,7 +375,7 @@ public function testQueriesForSpecificModelWithQuery(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(name: String! @eq): User
                 @can(ability: "view", query: true)
@@ -385,15 +385,15 @@ public function testQueriesForSpecificModelWithQuery(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($name: String!) {
             user(name: $name) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'name' => $user->name,
         ])->assertJson([
             'data' => [
@@ -414,7 +414,7 @@ public function testFailsToFindSpecificModelWithQuery(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @can(ability: "view", query: true)
@@ -424,15 +424,15 @@ public function testFailsToFindSpecificModelWithQuery(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -455,7 +455,7 @@ public function testHandleMultipleModelsWithQuery(): void
         $postB->user()->associate($admin);
         $postB->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             deletePosts(ids: [ID!]! @whereKey): [Post!]!
                 @can(ability: "delete", query: true)
@@ -465,15 +465,15 @@ public function testHandleMultipleModelsWithQuery(): void
         type Post {
             title: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($ids: [ID!]!) {
             deletePosts(ids: $ids) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'ids' => [$postA->id, $postB->id],
         ])->assertJson([
             'data' => [
@@ -499,7 +499,7 @@ public function testWorksWithSoftDeletesWithQuery(): void
         $this->assertInstanceOf(Task::class, $task);
         $task->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             task(id: ID! @whereKey): Task
                 @can(ability: "adminOnly", query: true)
@@ -510,15 +510,15 @@ public function testWorksWithSoftDeletesWithQuery(): void
         type Task {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id, trashed: WITH) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertJson([
             'data' => [
@@ -537,7 +537,7 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
 
         $user = factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!]!
                 @can(ability: "view", resolved: true)
@@ -547,9 +547,9 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 data {
@@ -557,7 +557,7 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'data' => [
@@ -583,7 +583,7 @@ public function testChecksAgainstRelation(): void
         $user->company()->associate($company);
         $user->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             company: Company @first
         }
@@ -597,9 +597,9 @@ public function testChecksAgainstRelation(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             company {
                 users {
@@ -607,7 +607,7 @@ public function testChecksAgainstRelation(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'company' => [
                     'users' => [
@@ -628,7 +628,7 @@ public function testChecksAgainstMissingResolvedModelWithFind(): void
 
         $user = factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID @whereKey): User
                 @can(ability: "view", resolved: true)
@@ -638,15 +638,15 @@ public function testChecksAgainstMissingResolvedModelWithFind(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
diff --git a/tests/Integration/Auth/CanFindDirectiveDBTest.php b/tests/Integration/Auth/CanFindDirectiveDBTest.php
index a6ac5fe73a..d24482bc00 100644
--- a/tests/Integration/Auth/CanFindDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanFindDirectiveDBTest.php
@@ -24,7 +24,7 @@ public function testQueriesForSpecificModel(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canFind(ability: "view", find: "id")
@@ -34,15 +34,15 @@ public function testQueriesForSpecificModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->getKey(),
         ])->assertJson([
             'data' => [
@@ -62,7 +62,7 @@ public function testCustomModelName(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             account(id: ID! @whereKey): Account
                 @canFind(ability: "view", find: "id", model: "User")
@@ -72,15 +72,15 @@ public function testCustomModelName(): void
         type Account {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             account(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->getKey(),
         ])->assertJson([
             'data' => [
@@ -101,7 +101,7 @@ public function testFailsToFindSpecificModel(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canFind(ability: "view", find: "id")
@@ -111,15 +111,15 @@ public function testFailsToFindSpecificModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -141,7 +141,7 @@ public function testThrowsCustomExceptionWhenFailsToFindModel(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canFind(ability: "view", find: "id")
@@ -151,18 +151,18 @@ public function testThrowsCustomExceptionWhenFailsToFindModel(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $this->rethrowGraphQLErrors();
 
         try {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: "not-present") {
                     name
                 }
             }
-            ');
+            GRAPHQL);
         } catch (Error $error) {
             $previous = $error->getPrevious();
 
@@ -181,7 +181,7 @@ public function testFailsToFindSpecificModelConcealException(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canFind(ability: "view", find: "id", action: EXCEPTION_NOT_AUTHORIZED)
@@ -191,15 +191,15 @@ public function testFailsToFindSpecificModelConcealException(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -220,7 +220,7 @@ public function testDoesntConcealResolverException(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             throwWhenInvoked(id: ID!): User
                 @canFind(ability: "view", find: "id", action: EXCEPTION_NOT_AUTHORIZED)
@@ -229,15 +229,15 @@ public function testDoesntConcealResolverException(): void
         type User {
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             throwWhenInvoked(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->getKey(),
         ])->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
     }
@@ -250,7 +250,7 @@ public function testFailsToFindSpecificModelWithFindOrFailFalse(): void
 
         $this->mockResolver(null);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canFind(ability: "view", find: "id", findOrFail: false)
@@ -260,15 +260,15 @@ public function testFailsToFindSpecificModelWithFindOrFailFalse(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => null,
             ],
@@ -281,7 +281,7 @@ public function testThrowsIfFindValueIsNotGiven(): void
         $user->name = UserPolicy::ADMIN;
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID): User
                 @canFind(ability: "view", find: "some.path")
@@ -291,15 +291,15 @@ public function testThrowsIfFindValueIsNotGiven(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLError(CanDirective::missingKeyToFindModel('some.path'));
+        GRAPHQL)->assertGraphQLError(CanDirective::missingKeyToFindModel('some.path'));
     }
 
     public function testFindUsingNestedInputWithDotNotation(): void
@@ -308,7 +308,7 @@ public function testFindUsingNestedInputWithDotNotation(): void
         $this->assertInstanceOf(User::class, $user);
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(input: FindUserInput!): User
                 @canFind(ability: "view", find: "input.id")
@@ -322,9 +322,9 @@ public function testFindUsingNestedInputWithDotNotation(): void
         input FindUserInput {
           id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(input: {
               id: $id
@@ -332,7 +332,7 @@ public function testFindUsingNestedInputWithDotNotation(): void
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -361,7 +361,7 @@ public function testThrowsIfNotAuthorized(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             post(foo: ID! @whereKey): Post
                 @canFind(ability: "view", find: "foo")
@@ -371,15 +371,15 @@ public function testThrowsIfNotAuthorized(): void
         type Post {
             title: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($foo: ID!) {
             post(foo: $foo) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'foo' => $post->id,
         ])->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
     }
@@ -400,7 +400,7 @@ public function testHandleMultipleModels(): void
         $postB->user()->associate($admin);
         $postB->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             deletePosts(ids: [ID!]! @whereKey): [Post!]!
                 @canFind(ability: "delete", find: "ids")
@@ -410,15 +410,15 @@ public function testHandleMultipleModels(): void
         type Post {
             title: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($ids: [ID!]!) {
             deletePosts(ids: $ids) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'ids' => [$postA->id, $postB->id],
         ])->assertJson([
             'data' => [
@@ -444,7 +444,7 @@ public function testWorksWithSoftDeletes(): void
         $this->assertInstanceOf(Task::class, $task);
         $task->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             task(id: ID! @whereKey): Task
                 @canFind(ability: "adminOnly", find: "id")
@@ -455,15 +455,15 @@ public function testWorksWithSoftDeletes(): void
         type Task {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id, trashed: WITH) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Auth/CanModelDirectiveDBTest.php b/tests/Integration/Auth/CanModelDirectiveDBTest.php
index e6f8d893d0..75e5fe46fa 100644
--- a/tests/Integration/Auth/CanModelDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanModelDirectiveDBTest.php
@@ -15,7 +15,7 @@ public function testDoesntConcealResolverException(): void
         $admin->name = UserPolicy::ADMIN;
         $this->be($admin);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             throwWhenInvoked: Task
                 @canModel(ability: "adminOnly", action: EXCEPTION_NOT_AUTHORIZED)
@@ -24,14 +24,14 @@ public function testDoesntConcealResolverException(): void
         type Task {
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             throwWhenInvoked {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
     }
 }
diff --git a/tests/Integration/Auth/CanQueryDirectiveDBTest.php b/tests/Integration/Auth/CanQueryDirectiveDBTest.php
index 669a16f736..5f6f30aa56 100644
--- a/tests/Integration/Auth/CanQueryDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanQueryDirectiveDBTest.php
@@ -20,7 +20,7 @@ public function testQueriesForSpecificModelWithQuery(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(name: String! @eq): User
                 @canQuery(ability: "view")
@@ -30,15 +30,15 @@ public function testQueriesForSpecificModelWithQuery(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($name: String!) {
             user(name: $name) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'name' => $user->name,
         ])->assertJson([
             'data' => [
@@ -59,7 +59,7 @@ public function testFailsToFindSpecificModelWithQuery(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canQuery(ability: "view", query: true)
@@ -69,15 +69,15 @@ public function testFailsToFindSpecificModelWithQuery(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -93,7 +93,7 @@ public function testDoesntConcealResolverException(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             throwWhenInvoked(id: ID!): User
                 @canQuery(ability: "view", action: EXCEPTION_NOT_AUTHORIZED)
@@ -102,15 +102,15 @@ public function testDoesntConcealResolverException(): void
         type User {
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             throwWhenInvoked(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->getKey(),
         ])->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
     }
@@ -131,7 +131,7 @@ public function testHandleMultipleModelsWithQuery(): void
         $postB->user()->associate($admin);
         $postB->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             deletePosts(ids: [ID!]! @whereKey): [Post!]!
                 @canQuery(ability: "delete")
@@ -141,15 +141,15 @@ public function testHandleMultipleModelsWithQuery(): void
         type Post {
             title: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($ids: [ID!]!) {
             deletePosts(ids: $ids) {
                 title
             }
         }
-        ', [
+        GRAPHQL, [
             'ids' => [$postA->id, $postB->id],
         ])->assertJson([
             'data' => [
@@ -175,7 +175,7 @@ public function testWorksWithSoftDeletesWithQuery(): void
         $this->assertInstanceOf(Task::class, $task);
         $task->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             task(id: ID! @whereKey): Task
                 @canQuery(ability: "adminOnly")
@@ -186,15 +186,15 @@ public function testWorksWithSoftDeletesWithQuery(): void
         type Task {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id, trashed: WITH) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Auth/CanResolvedDirectiveDBTest.php b/tests/Integration/Auth/CanResolvedDirectiveDBTest.php
index a0248458c4..0d83ad4823 100644
--- a/tests/Integration/Auth/CanResolvedDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanResolvedDirectiveDBTest.php
@@ -17,7 +17,7 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
 
         $user = factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!]!
                 @canResolved(ability: "view")
@@ -27,9 +27,9 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 data {
@@ -37,7 +37,7 @@ public function testChecksAgainstResolvedModelsFromPaginator(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'data' => [
@@ -63,7 +63,7 @@ public function testChecksAgainstRelation(): void
         $user->company()->associate($company);
         $user->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             company: Company @first
         }
@@ -77,9 +77,9 @@ public function testChecksAgainstRelation(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             company {
                 users {
@@ -87,7 +87,7 @@ public function testChecksAgainstRelation(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'company' => [
                     'users' => [
@@ -108,7 +108,7 @@ public function testChecksAgainstMissingResolvedModelWithFind(): void
 
         $user = factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @whereKey): User
                 @canResolved(ability: "view")
@@ -118,15 +118,15 @@ public function testChecksAgainstMissingResolvedModelWithFind(): void
         type User {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: "not-present") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
diff --git a/tests/Integration/Auth/CanRootDirectiveDBTest.php b/tests/Integration/Auth/CanRootDirectiveDBTest.php
index 53f86c0048..2bf2e01c6c 100644
--- a/tests/Integration/Auth/CanRootDirectiveDBTest.php
+++ b/tests/Integration/Auth/CanRootDirectiveDBTest.php
@@ -15,7 +15,7 @@ public function testDoesntConcealResolverException(): void
         $admin->name = UserPolicy::ADMIN;
         $this->be($admin);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             throwWhenInvoked: Task
         }
@@ -23,14 +23,14 @@ public function testDoesntConcealResolverException(): void
         type Task {
             name: String! @canRoot(ability: "adminOnly", action: EXCEPTION_NOT_AUTHORIZED)
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             throwWhenInvoked {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(ThrowWhenInvoked::ERROR_MESSAGE);
     }
 }
diff --git a/tests/Integration/AutomaticPersistedQueriesTest.php b/tests/Integration/AutomaticPersistedQueriesTest.php
index 04c8a49660..c2a925f67a 100644
--- a/tests/Integration/AutomaticPersistedQueriesTest.php
+++ b/tests/Integration/AutomaticPersistedQueriesTest.php
@@ -149,11 +149,11 @@ public function testConfigDisabled(): void
         $config->set('lighthouse.query_cache.enable', true);
         $config->set('lighthouse.persisted_queries', false);
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
 
         $sha256 = hash('sha256', $query);
 
@@ -192,11 +192,11 @@ public function testCacheDisabled(): void
         $config->set('lighthouse.query_cache.enable', false);
         $config->set('lighthouse.persisted_queries', true);
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
 
         $sha256 = hash('sha256', $query);
 
diff --git a/tests/Integration/Bind/BindDirectiveTest.php b/tests/Integration/Bind/BindDirectiveTest.php
index 93330deb1e..67e3592d42 100644
--- a/tests/Integration/Bind/BindDirectiveTest.php
+++ b/tests/Integration/Bind/BindDirectiveTest.php
@@ -21,7 +21,7 @@ final class BindDirectiveTest extends DBTestCase
 
     public function testSchemaValidationFailsWhenClassArgumentDefinedOnFieldArgumentIsNotAClass(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -29,23 +29,23 @@ public function testSchemaValidationFailsWhenClassArgumentDefinedOnFieldArgument
             type Query {
                 user(user: ID! @bind(class: "NotAClass")): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             '@bind argument `class` defined on `user.user` must be an existing class, received `NotAClass`.',
         ));
-        $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(user: "1") {
                     id
                 }
             }
-            GRAPHQL);
+        GRAPHQL);
     }
 
     public function testSchemaValidationFailsWhenClassArgumentDefinedOnInputFieldIsNotAClass(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -57,27 +57,25 @@ public function testSchemaValidationFailsWhenClassArgumentDefinedOnInputFieldIsN
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             '@bind argument `class` defined on `RemoveUsersInput.users` must be an existing class, received `NotAClass`.',
         ));
-        $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => ['1'],
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => ['1'],
             ],
-        );
+        ]);
     }
 
     public function testSchemaValidationFailsWhenClassArgumentDefinedOnFieldArgumentIsNotAModelOrCallableClass(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -85,23 +83,23 @@ public function testSchemaValidationFailsWhenClassArgumentDefinedOnFieldArgument
             type Query {
                 user(user: ID! @bind(class: "stdClass")): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             '@bind argument `class` defined on `user.user` must extend Illuminate\Database\Eloquent\Model or define the method `__invoke`, but `stdClass` does neither.',
         ));
-        $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(user: "1") {
                     id
                 }
             }
-            GRAPHQL);
+        GRAPHQL);
     }
 
     public function testSchemaValidationFailsWhenClassArgumentDefinedOnInputFieldIsNotAModelOrCallableClass(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -113,22 +111,20 @@ public function testSchemaValidationFailsWhenClassArgumentDefinedOnInputFieldIsN
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             '@bind argument `class` defined on `RemoveUsersInput.users` must extend Illuminate\Database\Eloquent\Model or define the method `__invoke`, but `stdClass` does neither.',
         ));
-        $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => ['1'],
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => ['1'],
             ],
-        );
+        ]);
     }
 
     public function testModelBindingOnFieldArgument(): void
@@ -137,7 +133,7 @@ public function testModelBindingOnFieldArgument(): void
 
         $this->mockResolver(fn (mixed $root, array $args): User => $args['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -145,17 +141,17 @@ public function testModelBindingOnFieldArgument(): void
             type Query {
                 user(user: ID! @bind(class: "Tests\\Utils\\Models\\User")): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => $user->getKey()],
-        );
+        GRAPHQL, [
+            'id' => $user->getKey(),
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -168,7 +164,7 @@ public function testModelBindingOnFieldArgument(): void
 
     public function testMissingModelBindingOnFieldArgument(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -176,15 +172,15 @@ public function testMissingModelBindingOnFieldArgument(): void
             type Query {
                 user(user: ID! @bind(class: "Tests\\Utils\\Models\\User")): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(user: "1") {
                     id
                 }
             }
-            GRAPHQL);
+        GRAPHQL);
         $response->assertOk();
         $response->assertGraphQLValidationError('user', trans('validation.exists', ['attribute' => 'user']));
     }
@@ -192,7 +188,7 @@ public function testMissingModelBindingOnFieldArgument(): void
     public function testMissingOptionalModelBindingOnFieldArgument(): void
     {
         $this->mockResolver(fn (mixed $root, array $args) => $args['user']);
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -202,17 +198,17 @@ public function testMissingOptionalModelBindingOnFieldArgument(): void
                     user: ID! @bind(class: "Tests\\Utils\\Models\\User", required: false)
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => '1'],
-        );
+        GRAPHQL, [
+            'id' => '1',
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -227,7 +223,7 @@ public function testModelBindingByColumnOnFieldArgument(): void
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -237,17 +233,17 @@ public function testModelBindingByColumnOnFieldArgument(): void
                     user: String! @bind(class: "Tests\\Utils\\Models\\User", column: "email")
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($email: String!) {
                 user(user: $email) {
                     id
                 }
             }
-            GRAPHQL,
-            ['email' => $user->email],
-        );
+        GRAPHQL, [
+            'email' => $user->email,
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -269,7 +265,7 @@ public function testModelBindingWithEagerLoadingOnFieldArgument(): void
             return $args['user'];
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -279,17 +275,17 @@ public function testModelBindingWithEagerLoadingOnFieldArgument(): void
                     user: ID! @bind(class: "Tests\\Utils\\Models\\User", with: ["company"])
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => $user->getKey()],
-        );
+        GRAPHQL, [
+            'id' => $user->getKey(),
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -313,7 +309,7 @@ public function testModelBindingWithTooManyResultsOnFieldArgument(): void
             $user->save();
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -323,17 +319,17 @@ public function testModelBindingWithTooManyResultsOnFieldArgument(): void
                     user: String! @bind(class: "Tests\\Utils\\Models\\User", column: "name")
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $makeRequest = fn (): TestResponse => $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $makeRequest = fn (): TestResponse => $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($name: String!) {
                 user(user: $name) {
                     id
                 }
             }
-            GRAPHQL,
-            ['name' => $users->first()->name],
-        );
+        GRAPHQL, [
+            'name' => $users->first()->name,
+        ]);
         $this->assertThrowsMultipleRecordsFoundException($makeRequest, $users->count());
     }
 
@@ -348,7 +344,7 @@ public function testModelCollectionBindingOnFieldArgument(): void
             return true;
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -358,15 +354,15 @@ public function testModelCollectionBindingOnFieldArgument(): void
                     users: [ID!]! @bind(class: "Tests\\Utils\\Models\\User")
                 ): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($users: [ID!]!) {
                 removeUsers(users: $users)
             }
-            GRAPHQL,
-            ['users' => $users->map(fn (User $user): int => $user->getKey())],
-        );
+        GRAPHQL, [
+            'users' => $users->map(fn (User $user): int => $user->getKey()),
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -385,7 +381,7 @@ public function testMissingModelCollectionBindingOnFieldArgument(): void
     {
         $user = factory(User::class)->create();
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -395,17 +391,15 @@ public function testMissingModelCollectionBindingOnFieldArgument(): void
                     users: [ID!]! @bind(class: "Tests\\Utils\\Models\\User")
                 ): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($users: [ID!]!) {
                 removeUsers(users: $users)
             }
-            GRAPHQL,
-            [
-                'users' => [$user->getKey(), '10'],
-            ],
-        );
+        GRAPHQL, [
+            'users' => [$user->getKey(), '10'],
+        ]);
         $response->assertOk();
         $response->assertGraphQLValidationError('users.1', trans('validation.exists', ['attribute' => 'users.1']));
     }
@@ -421,7 +415,7 @@ public function testMissingOptionalModelCollectionBindingOnFieldArgument(): void
             return true;
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -431,17 +425,15 @@ public function testMissingOptionalModelCollectionBindingOnFieldArgument(): void
                     users: [ID!]! @bind(class: "Tests\\Utils\\Models\\User", required: false)
                 ): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($users: [ID!]!) {
                 removeUsers(users: $users)
             }
-            GRAPHQL,
-            [
-                'users' => [$user->getKey(), '10'],
-            ],
-        );
+        GRAPHQL, [
+            'users' => [$user->getKey(), '10'],
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -464,7 +456,7 @@ public function testModelCollectionBindingWithTooManyResultsOnFieldArgument(): v
             $user->save();
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -474,17 +466,15 @@ public function testModelCollectionBindingWithTooManyResultsOnFieldArgument(): v
                     users: [String!]! @bind(class: "Tests\\Utils\\Models\\User", column: "name")
                 ): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $makeRequest = fn (): TestResponse => $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $makeRequest = fn (): TestResponse => $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($users: [String!]!) {
                 removeUsers(users: $users)
             }
-            GRAPHQL,
-            [
-                'users' => [$users->first()->name],
-            ],
-        );
+        GRAPHQL, [
+            'users' => [$users->first()->name],
+        ]);
         $this->assertThrowsMultipleRecordsFoundException($makeRequest, $users->count());
     }
 
@@ -494,7 +484,7 @@ public function testModelBindingOnInputField(): void
 
         $this->mockResolver(fn (mixed $root, array $args): User => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -506,21 +496,19 @@ public function testModelBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => $user->getKey(),
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => $user->getKey(),
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -533,7 +521,7 @@ public function testModelBindingOnInputField(): void
 
     public function testMissingModelBindingOnInputField(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -545,21 +533,19 @@ public function testMissingModelBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => '1',
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => '1',
             ],
-        );
+        ]);
         $response->assertOk();
         $response->assertGraphQLValidationError('input.user', trans('validation.exists', [
             'attribute' => 'input.user',
@@ -570,7 +556,7 @@ public function testMissingOptionalModelBindingOnInputField(): void
     {
         $this->mockResolver(fn (mixed $root, array $args) => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -582,21 +568,19 @@ public function testMissingOptionalModelBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => '1',
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => '1',
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -611,7 +595,7 @@ public function testModelBindingByColumnOnInputField(): void
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -623,21 +607,19 @@ public function testModelBindingByColumnOnInputField(): void
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => $user->email,
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => $user->email,
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -659,7 +641,7 @@ public function testModelBindingWithEagerLoadingOnInputField(): void
             return $args['input']['user'];
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -671,21 +653,19 @@ public function testModelBindingWithEagerLoadingOnInputField(): void
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => $user->getKey(),
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => $user->getKey(),
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -709,7 +689,7 @@ public function testModelBindingWithTooManyResultsOnInputField(): void
             $user->save();
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -721,21 +701,19 @@ public function testModelBindingWithTooManyResultsOnInputField(): void
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $makeRequest = fn (): TestResponse => $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $makeRequest = fn (): TestResponse => $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => $users->first()->name,
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => $users->first()->name,
             ],
-        );
+        ]);
         $this->assertThrowsMultipleRecordsFoundException($makeRequest, $users->count());
     }
 
@@ -750,7 +728,7 @@ public function testModelCollectionBindingOnInputField(): void
             return true;
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -762,19 +740,17 @@ public function testModelCollectionBindingOnInputField(): void
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => $users->map(fn (User $user): int => $user->getKey()),
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => $users->map(fn (User $user): int => $user->getKey()),
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -794,7 +770,7 @@ public function testMissingModelCollectionBindingOnInputField(): void
     {
         $user = factory(User::class)->create();
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -806,19 +782,17 @@ public function testMissingModelCollectionBindingOnInputField(): void
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => [$user->getKey(), '10'],
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => [$user->getKey(), '10'],
             ],
-        );
+        ]);
         $response->assertOk();
         $response->assertGraphQLValidationError('input.users.1', trans('validation.exists', [
             'attribute' => 'input.users.1',
@@ -836,7 +810,7 @@ public function testMissingOptionalModelCollectionBindingOnInputField(): void
             return true;
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -848,19 +822,17 @@ public function testMissingOptionalModelCollectionBindingOnInputField(): void
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => [$user->getKey(), '10'],
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => [$user->getKey(), '10'],
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -884,7 +856,7 @@ public function testModelCollectionBindingWithTooManyResultsOnInputField(): void
             $user->save();
         });
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -896,19 +868,17 @@ public function testModelCollectionBindingWithTooManyResultsOnInputField(): void
             type Mutation {
                 removeUsers(input: RemoveUsersInput!): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $makeRequest = fn (): TestResponse => $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $makeRequest = fn (): TestResponse => $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: RemoveUsersInput!) {
                 removeUsers(input: $input)
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'users' => [$users->first()->name],
-                ],
+        GRAPHQL, [
+            'input' => [
+                'users' => [$users->first()->name],
             ],
-        );
+        ]);
         $this->assertThrowsMultipleRecordsFoundException($makeRequest, $users->count());
     }
 
@@ -919,7 +889,7 @@ public function testCallableClassBindingOnFieldArgument(): void
 
         $this->mockResolver(fn (mixed $root, array $args): User => $args['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -927,17 +897,17 @@ public function testCallableClassBindingOnFieldArgument(): void
             type Query {
                 user(user: ID! @bind(class: "Tests\\Utils\\Bind\\SpyCallableClassBinding")): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => $user->getKey()],
-        );
+        GRAPHQL, [
+            'id' => $user->getKey(),
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -952,7 +922,7 @@ public function testMissingCallableClassBindingOnFieldArgument(): void
     {
         $this->instance(SpyCallableClassBinding::class, new SpyCallableClassBinding(null));
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -962,17 +932,17 @@ public function testMissingCallableClassBindingOnFieldArgument(): void
                     user: ID! @bind(class: "Tests\\Utils\\Bind\\SpyCallableClassBinding")
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => '1'],
-        );
+        GRAPHQL, [
+            'id' => '1',
+        ]);
         $response->assertOk();
         $response->assertGraphQLValidationError('user', trans('validation.exists', ['attribute' => 'user']));
     }
@@ -983,7 +953,7 @@ public function testMissingOptionalCallableClassBindingOnFieldArgument(): void
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -993,17 +963,17 @@ public function testMissingOptionalCallableClassBindingOnFieldArgument(): void
                     user: ID! @bind(class: "Tests\\Utils\\Bind\\SpyCallableClassBinding", required: false)
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => '1'],
-        );
+        GRAPHQL, [
+            'id' => '1',
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -1019,7 +989,7 @@ public function testCallableClassBindingWithDirectiveArgumentsOnFieldArgument():
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1034,17 +1004,17 @@ class: "Tests\\Utils\\Bind\\SpyCallableClassBinding"
                     )
                 ): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(user: $id) {
                     id
                 }
             }
-            GRAPHQL,
-            ['id' => '1'],
-        );
+        GRAPHQL, [
+            'id' => '1',
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -1065,7 +1035,7 @@ public function testCallableClassBindingOnInputField(): void
 
         $this->mockResolver(fn (mixed $root, array $args): User => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1077,21 +1047,19 @@ public function testCallableClassBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => $user->getKey(),
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => $user->getKey(),
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -1106,7 +1074,7 @@ public function testMissingCallableClassBindingOnInputField(): void
     {
         $this->instance(SpyCallableClassBinding::class, new SpyCallableClassBinding(null));
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1118,21 +1086,19 @@ public function testMissingCallableClassBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User! @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => '1',
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => '1',
             ],
-        );
+        ]);
         $response->assertOk();
         $response->assertGraphQLValidationError('input.user', trans('validation.exists', ['attribute' => 'input.user']));
     }
@@ -1143,7 +1109,7 @@ public function testMissingOptionalCallableClassBindingOnInputField(): void
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1155,21 +1121,19 @@ public function testMissingOptionalCallableClassBindingOnInputField(): void
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => '1',
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => '1',
             ],
-        );
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
@@ -1185,7 +1149,7 @@ public function testCallableClassBindingWithDirectiveArgumentsOnInputField(): vo
 
         $this->mockResolver(fn (mixed $root, array $args) => $args['input']['user']);
 
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1202,21 +1166,19 @@ class: "Tests\\Utils\\Bind\\SpyCallableClassBinding"
             type Query {
                 user(input: UserInput!): User @mock
             }
-            GRAPHQL;
+        GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($input: UserInput!) {
                 user(input: $input) {
                     id
                 }
             }
-            GRAPHQL,
-            [
-                'input' => [
-                    'user' => '1',
-                ],
+        GRAPHQL, [
+            'input' => [
+                'user' => '1',
             ],
-        );
+        ]);
 
         $response->assertGraphQLErrorFree();
         $response->assertJson([
@@ -1243,7 +1205,7 @@ public function testMultipleBindingsInSameRequest(): void
             return true;
         });
 
-        $this->schema =  /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema =  /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
             }
@@ -1258,18 +1220,16 @@ public function testMultipleBindingsInSameRequest(): void
                     company: ID! @bind(class: "Tests\\Utils\\Models\\Company")
                 ): Boolean! @mock
             }
-            GRAPHQL . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($user: ID!, $company: ID!) {
                 addUserToCompany(user: $user, company: $company)
             }
-            GRAPHQL,
-            [
-                'user' => $user->getKey(),
-                'company' => $company->getKey(),
-            ],
-        );
+        GRAPHQL, [
+            'user' => $user->getKey(),
+            'company' => $company->getKey(),
+        ]);
         $response->assertGraphQLErrorFree();
         $response->assertJson([
             'data' => [
diff --git a/tests/Integration/Cache/CacheDirectiveTest.php b/tests/Integration/Cache/CacheDirectiveTest.php
index aa0edebd19..cee9be8d4a 100644
--- a/tests/Integration/Cache/CacheDirectiveTest.php
+++ b/tests/Integration/Cache/CacheDirectiveTest.php
@@ -30,7 +30,7 @@ public function testStoreResolverResultInCache(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String @cache
@@ -39,15 +39,15 @@ public function testStoreResolverResultInCache(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -60,7 +60,7 @@ public function testStoreResolverResultInCache(): void
 
     public function testCacheKeyIsValidOnFieldDefinition(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type User {
                 id: ID!
                 name: String @cache
@@ -70,7 +70,7 @@ public function testCacheKeyIsValidOnFieldDefinition(): void
             type Query {
                 user: User @first
             }
-        ';
+        GRAPHQL;
 
         $schemaValidator = $this->app->make(SchemaValidator::class);
 
@@ -87,7 +87,7 @@ public function testPlaceCacheKeyOnAnyField(): void
             'email' => 'foo@bar.com',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String @cache
@@ -97,15 +97,15 @@ public function testPlaceCacheKeyOnAnyField(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -124,7 +124,7 @@ public function testCacheKeyWithRenameDirective(): void
             'email_name' => 'foo@bar.com',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String @cache
@@ -134,15 +134,15 @@ public function testCacheKeyWithRenameDirective(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -160,7 +160,7 @@ public function testIDCacheKeyWithRenameDirective(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID! @rename(attribute: "id_")
             name: String @cache
@@ -169,15 +169,15 @@ public function testIDCacheKeyWithRenameDirective(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -199,7 +199,7 @@ public function testStoreResolverResultInPrivateCache(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String @cache(private: true)
@@ -208,15 +208,15 @@ public function testStoreResolverResultInPrivateCache(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -234,7 +234,7 @@ public function testStoreResolverResultInCacheWhenUsingNodeDirective(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -247,15 +247,15 @@ public function testStoreResolverResultInCacheWhenUsingNodeDirective(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -273,7 +273,7 @@ public function testFallsBackToPublicCacheIfUserIsNotAuthenticated(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String @cache(private: true)
@@ -282,15 +282,15 @@ public function testFallsBackToPublicCacheIfUserIsNotAuthenticated(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foobar',
@@ -305,7 +305,7 @@ public function testStorePaginateResolverInCache(): void
     {
         factory(User::class, 5)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -314,9 +314,9 @@ public function testStorePaginateResolverInCache(): void
         type Query {
             users: [User] @paginate(type: PAGINATOR, model: "User") @cache
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 5) {
                 paginatorInfo {
@@ -328,7 +328,7 @@ public function testStorePaginateResolverInCache(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $result = $this->cache->get('lighthouse:Query::users:first:5');
 
@@ -347,7 +347,7 @@ public function testCacheHasManyResolver(): void
             $post->save();
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String
@@ -362,9 +362,9 @@ public function testCacheHasManyResolver(): void
         type Query {
             user(id: ID! @eq): User @find(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 id
@@ -376,7 +376,7 @@ public function testCacheHasManyResolver(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $dbQueryCountForPost = 0;
         DB::listen(static function (QueryExecuted $query) use (&$dbQueryCountForPost): void {
@@ -418,7 +418,7 @@ public function testAttachTagsToCache(): void
 
         $tags = ['lighthouse:User:1', 'lighthouse:User:1:posts'];
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String
@@ -433,9 +433,9 @@ public function testAttachTagsToCache(): void
         type Query {
             user(id: ID! @eq): User @find(model: "User") @cache
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 id
@@ -447,7 +447,7 @@ public function testAttachTagsToCache(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $dbQueryCountForPost = 0;
         DB::listen(static function (QueryExecuted $query) use (&$dbQueryCountForPost): void {
@@ -486,7 +486,7 @@ public function testUseFalsyResultsInCache(): void
             'field_integer' => 1,
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             field_boolean: Boolean @cache
@@ -497,7 +497,7 @@ public function testUseFalsyResultsInCache(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $this->cache->setMultiple([
             'lighthouse:User:1:field_boolean' => false,
@@ -505,7 +505,7 @@ public function testUseFalsyResultsInCache(): void
             'lighthouse:User:1:field_integer' => 0,
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 field_boolean
@@ -513,7 +513,7 @@ public function testUseFalsyResultsInCache(): void
                 field_integer
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'field_boolean' => false,
diff --git a/tests/Integration/Cache/ClearCacheDirectiveTest.php b/tests/Integration/Cache/ClearCacheDirectiveTest.php
index a9f62c413c..4313b3fcbf 100644
--- a/tests/Integration/Cache/ClearCacheDirectiveTest.php
+++ b/tests/Integration/Cache/ClearCacheDirectiveTest.php
@@ -20,11 +20,11 @@ protected function setUp(): void
 
     public function testClearCacheForEntireType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo: Int! @clearCache(type: "Foo")
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:']);
 
@@ -33,22 +33,22 @@ public function testClearCacheForEntireType(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
 
     public function testClearCacheForAllFieldsOfType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo: Int! @clearCache(type: "Foo", field: "bar")
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo::bar']);
 
@@ -57,22 +57,22 @@ public function testClearCacheForAllFieldsOfType(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
 
     public function testClearCacheForTypeWithIDByArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo(id: ID!): Int! @clearCache(type: "Foo", idSource: { argument: "id" })
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:1']);
 
@@ -81,18 +81,18 @@ public function testClearCacheForTypeWithIDByArgument(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo(id: 1)
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
 
     public function testClearCacheForTypeWithIDByArgumentNestedPath(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         input FooInput {
             id: ID!
         }
@@ -100,7 +100,7 @@ public function testClearCacheForTypeWithIDByArgumentNestedPath(): void
         type Mutation {
             foo(input: FooInput!): Int! @clearCache(type: "Foo", idSource: { argument: "input.id" })
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:1']);
 
@@ -109,11 +109,11 @@ public function testClearCacheForTypeWithIDByArgumentNestedPath(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo(input: { id: 1 })
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
@@ -124,7 +124,7 @@ public function testClearCacheForTypeWithIDByField(): void
             'bar' => 2,
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar: Int!
         }
@@ -134,7 +134,7 @@ public function testClearCacheForTypeWithIDByField(): void
                 @mock
                 @clearCache(type: "Foo", idSource: { field: "bar" })
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:2']);
 
@@ -143,13 +143,13 @@ public function testClearCacheForTypeWithIDByField(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo {
                 bar
             }
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
@@ -166,7 +166,7 @@ public function testClearCacheForMultipleTypesWithIDByField(): void
             ],
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar: Int!
         }
@@ -176,7 +176,7 @@ public function testClearCacheForMultipleTypesWithIDByField(): void
                 @mock
                 @clearCache(type: "Foo", idSource: { field: "*.bar" })
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache1 = $this->cache->tags(['lighthouse:Foo:1']);
         $taggedCache2 = $this->cache->tags(['lighthouse:Foo:2']);
@@ -188,13 +188,13 @@ public function testClearCacheForMultipleTypesWithIDByField(): void
         $this->assertTrue($taggedCache1->has($key));
         $this->assertTrue($taggedCache2->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foos {
                 bar
             }
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache1->has($key));
         $this->assertFalse($taggedCache2->has($key));
@@ -208,7 +208,7 @@ public function testClearCacheForTypeWithIDByFieldNestedPath(): void
             ],
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Bar {
             baz: Int!
         }
@@ -222,7 +222,7 @@ public function testClearCacheForTypeWithIDByFieldNestedPath(): void
                 @mock
                 @clearCache(type: "Foo", idSource: { field: "bar.baz" })
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:3']);
 
@@ -231,7 +231,7 @@ public function testClearCacheForTypeWithIDByFieldNestedPath(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo {
                 bar {
@@ -239,18 +239,18 @@ public function testClearCacheForTypeWithIDByFieldNestedPath(): void
                 }
             }
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
 
     public function testClearCacheForTypeWithIDByArgumentForField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo(id: ID!): Int! @clearCache(type: "Foo", idSource: { argument: "id" }, field: "baz")
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $taggedCache = $this->cache->tags(['lighthouse:Foo:1:baz']);
 
@@ -259,11 +259,11 @@ public function testClearCacheForTypeWithIDByArgumentForField(): void
 
         $this->assertTrue($taggedCache->has($key));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo(id: 1)
         }
-        ')->assertGraphQLErrorFree();
+        GRAPHQL)->assertGraphQLErrorFree();
 
         $this->assertFalse($taggedCache->has($key));
     }
diff --git a/tests/Integration/CacheControl/CacheControlDirectiveTest.php b/tests/Integration/CacheControl/CacheControlDirectiveTest.php
index 67a0ec4012..5fa6d55c25 100644
--- a/tests/Integration/CacheControl/CacheControlDirectiveTest.php
+++ b/tests/Integration/CacheControl/CacheControlDirectiveTest.php
@@ -18,7 +18,7 @@ public function testDefaultAppResponseHeader(): void
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String
@@ -27,15 +27,15 @@ public function testDefaultAppResponseHeader(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertHeader('Cache-Control', 'no-cache, private');
+        GRAPHQL)->assertHeader('Cache-Control', 'no-cache, private');
     }
 
     public function testInheritance(): void
@@ -44,7 +44,7 @@ public function testInheritance(): void
             'id' => 1,
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -52,15 +52,15 @@ public function testInheritance(): void
         type Query {
             me: User @mock @cacheControl(maxAge: 5, scope: PRIVATE)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             me {
                 id
             }
         }
-        ')->assertHeader('Cache-Control', 'max-age=5, private');
+        GRAPHQL)->assertHeader('Cache-Control', 'max-age=5, private');
     }
 
     /** @dataProvider rootScalarDataProvider */
@@ -69,12 +69,12 @@ public function testRootScalar(string $query, string $expectedHeaderString): voi
     {
         $this->mockResolver(1);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             default: ID @mock
             withDirective: ID @mock @cacheControl(maxAge: 5)
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($query)
             ->assertHeader('Cache-Control', $expectedHeaderString);
@@ -83,26 +83,26 @@ public function testRootScalar(string $query, string $expectedHeaderString): voi
     /** @return iterable<array{string, string}> */
     public static function rootScalarDataProvider(): iterable
     {
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 default
             }
-            ',
+        GRAPHQL,
             'no-cache, private',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 withDirective
             }
-            ',
+        GRAPHQL,
             'max-age=5, public',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 default
                 withDirective
             }
-            ',
+        GRAPHQL,
             'no-cache, private',
         ];
     }
@@ -114,7 +114,7 @@ public function testInheritanceWithNonScalar(): void
             'self' => null,
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             child: User
@@ -123,9 +123,9 @@ public function testInheritanceWithNonScalar(): void
         type Query {
             me: User @mock @cacheControl(maxAge: 5, scope: PRIVATE)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             me {
                 child {
@@ -133,7 +133,7 @@ public function testInheritanceWithNonScalar(): void
                 }
             }
         }
-        ')->assertHeader('Cache-Control', 'no-cache, private');
+        GRAPHQL)->assertHeader('Cache-Control', 'no-cache, private');
     }
 
     /** @dataProvider argumentsDataProvider */
@@ -145,7 +145,7 @@ public function testDirectiveArguments(string $directive, string $expectedHeader
             'name' => 'foobar',
         ]);
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type User {
             id: ID!
             name: String {$directive}
@@ -154,15 +154,15 @@ public function testDirectiveArguments(string $directive, string $expectedHeader
         type Query {
             user: User @mock @cacheControl(maxAge:50)
         }
-        ";
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertHeader('Cache-Control', $expectedHeaderString);
+        GRAPHQL)->assertHeader('Cache-Control', $expectedHeaderString);
     }
 
     /** @return iterable<array{string, string}> */
@@ -180,7 +180,7 @@ public static function argumentsDataProvider(): iterable
     #[DataProvider('nestedQueryDataProvider')]
     public function testUseDirectiveNested(string $query, string $expectedHeaderString): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany @cacheControl(maxAge: 50)
             posts: [Post!]! @hasMany
@@ -206,7 +206,7 @@ public function testUseDirectiveNested(string $query, string $expectedHeaderStri
             team: Team @first @cacheControl
             teamWithCache: Team @first @cacheControl(maxAge: 20)
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -230,7 +230,7 @@ public function testUseDirectiveNested(string $query, string $expectedHeaderStri
     /** @return iterable<array{string, string}> */
     public static function nestedQueryDataProvider(): iterable
     {
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks {
@@ -239,10 +239,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'max-age=5, private',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks {
@@ -250,10 +250,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'max-age=5, private',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 team {
                     users {
@@ -263,10 +263,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'no-cache, public',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 team {
                     users {
@@ -276,10 +276,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'no-cache, public',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 teamWithCache {
                     users {
@@ -289,10 +289,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'max-age=20, public',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 teamWithCache {
                     users {
@@ -302,10 +302,10 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'no-cache, public',
         ];
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 teamWithCache {
                     users {
@@ -316,14 +316,14 @@ public static function nestedQueryDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'no-cache, private',
         ];
     }
 
     public function testUsePaginate(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR) @cacheControl(maxAge: 50)
         }
@@ -337,7 +337,7 @@ public function testUsePaginate(): void
         type Query {
             users: [User] @paginate @cacheControl(maxAge: 5, scope: PRIVATE)
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -345,7 +345,7 @@ public function testUsePaginate(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(first: 10) {
                     paginatorInfo {
@@ -361,7 +361,7 @@ public function testUsePaginate(): void
                    }
                 }
             }
-            ')
+        GRAPHQL)
             ->assertHeader('Cache-Control', 'max-age=5, private');
     }
 
@@ -369,7 +369,7 @@ public function testUsePaginate(): void
     #[DataProvider('typeLevelCacheDataProvider')]
     public function testTypeLevelCache(string $query, string $expectedHeaderString): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany
             tasksWithCache: [Task!]! @hasMany(relation: "tasks") @cacheControl(maxAge: 20)
@@ -384,7 +384,7 @@ public function testTypeLevelCache(string $query, string $expectedHeaderString):
         type Query {
             user: User @first @cacheControl(maxAge: 50, scope: PRIVATE)
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -399,7 +399,7 @@ public function testTypeLevelCache(string $query, string $expectedHeaderString):
     /** @return iterable<array{string, string}> */
     public static function typeLevelCacheDataProvider(): iterable
     {
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks {
@@ -408,11 +408,11 @@ public static function typeLevelCacheDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'max-age=10, private',
         ];
 
-        yield [/** @lang GraphQL */ '
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasksWithCache {
@@ -421,7 +421,7 @@ public static function typeLevelCacheDataProvider(): iterable
                     }
                 }
             }
-            ',
+        GRAPHQL,
             'max-age=20, private',
         ];
     }
diff --git a/tests/Integration/CustomDefaultResolverTest.php b/tests/Integration/CustomDefaultResolverTest.php
index a316cba684..f16e40e44f 100644
--- a/tests/Integration/CustomDefaultResolverTest.php
+++ b/tests/Integration/CustomDefaultResolverTest.php
@@ -15,7 +15,7 @@ public function testSpecifyACustomDefaultResolver(): void
             'bar' => 'should not be returned',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo @mock
         }
@@ -23,19 +23,19 @@ public function testSpecifyACustomDefaultResolver(): void
         type Foo {
             bar: Int
         }
-        ';
+        GRAPHQL;
 
         $previous = Executor::getDefaultFieldResolver();
 
         Executor::setDefaultFieldResolver(static fn (): int => self::CUSTOM_RESOLVER_RESULT);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 bar
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'bar' => self::CUSTOM_RESOLVER_RESULT,
diff --git a/tests/Integration/DefaultSchemaTest.php b/tests/Integration/DefaultSchemaTest.php
index 79ec0e00fb..9302328c63 100644
--- a/tests/Integration/DefaultSchemaTest.php
+++ b/tests/Integration/DefaultSchemaTest.php
@@ -48,24 +48,24 @@ public function testPassesValidation(): void
     public function testFindRequiresExactlyOneArgument(): void
     {
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('email', 'The email field is required when id is not present.')
             ->assertGraphQLValidationError('id', 'The id field is required when email is not present.');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: 1, email: "foo@bar.baz") {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('email', 'The email field prohibits id from being present.')
             ->assertGraphQLValidationError('id', 'The id field prohibits email from being present.');
     }
@@ -76,13 +76,13 @@ public function testFindById(): void
         $user = factory(User::class)->create();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user(id: $id) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $user->id,
             ])
             ->assertExactJson([
@@ -97,7 +97,7 @@ public function testFindById(): void
     public function testEmptyUsers(): void
     {
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     data {
@@ -105,7 +105,7 @@ public function testEmptyUsers(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'users' => [
@@ -121,7 +121,7 @@ public function testAllUsers(): void
         factory(User::class)->times($amount)->create();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     data {
@@ -129,7 +129,7 @@ public function testAllUsers(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(2, 'data.users.data');
     }
 
@@ -156,7 +156,7 @@ public function testUsersByName(): void
 
     private function usersByName(string $name): TestResponse
     {
-        return $this->graphQL(/** @lang GraphQL */ '
+        return $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($name: String!) {
                 users(name: $name) {
                     data {
@@ -164,7 +164,7 @@ private function usersByName(string $name): TestResponse
                     }
                 }
             }
-            ',
+        GRAPHQL,
             [
                 'name' => $name,
             ],
diff --git a/tests/Integration/Defer/DeferDBTest.php b/tests/Integration/Defer/DeferDBTest.php
index b111fc0481..47357fcbb1 100644
--- a/tests/Integration/Defer/DeferDBTest.php
+++ b/tests/Integration/Defer/DeferDBTest.php
@@ -33,7 +33,7 @@ public function testDeferBelongsToFields(): void
 
         $this->mockResolver($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -46,11 +46,11 @@ public function testDeferBelongsToFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $this->countQueries($queryCount);
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 email
@@ -59,7 +59,7 @@ public function testDeferBelongsToFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(1, $queryCount);
         $this->assertCount(2, $chunks);
@@ -91,7 +91,7 @@ public function testDeferNestedRelationshipFields(): void
 
         $this->mockResolver($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
             users: [User] @hasMany
@@ -105,11 +105,11 @@ public function testDeferNestedRelationshipFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $this->countQueries($queryCount);
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 email
@@ -121,7 +121,7 @@ public function testDeferNestedRelationshipFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(2, $queryCount);
         $this->assertCount(3, $chunks);
@@ -162,7 +162,7 @@ public function testDeferNestedListFields(): void
 
         $this->mockResolver($companies);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
             users: [User] @hasMany
@@ -176,11 +176,11 @@ public function testDeferNestedListFields(): void
         type Query {
             companies: [Company] @mock
         }
-        ';
+        GRAPHQL;
 
         $this->countQueries($queryCount);
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             companies {
                 name
@@ -192,7 +192,7 @@ public function testDeferNestedListFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(2, $queryCount);
         $this->assertCount(3, $chunks);
diff --git a/tests/Integration/Defer/DeferIncludeSkipTest.php b/tests/Integration/Defer/DeferIncludeSkipTest.php
index f937903ea8..7d82337b96 100644
--- a/tests/Integration/Defer/DeferIncludeSkipTest.php
+++ b/tests/Integration/Defer/DeferIncludeSkipTest.php
@@ -7,10 +7,10 @@
 
 final class DeferIncludeSkipTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     directive @include(if: Boolean!) on FIELD
     directive @skip(if: Boolean!) on FIELD
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . "\n" . self::PLACEHOLDER_QUERY;
 
     protected function getPackageProviders($app): array
     {
@@ -22,33 +22,33 @@ protected function getPackageProviders($app): array
 
     public function testDoesNotDeferWithIncludeFalse(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo @defer @include(if: false)
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [],
         ]);
     }
 
     public function testDoesDeferWithIncludeTrue(): void
     {
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo @defer @include(if: true)
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
     }
 
     public function testDoesNotDeferWithIncludeFalseFromVariable(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($include: Boolean!) {
             foo @defer @include(if: $include)
         }
-        ', [
+        GRAPHQL, [
             'include' => false,
         ])->assertExactJson([
             'data' => [],
@@ -57,33 +57,33 @@ public function testDoesNotDeferWithIncludeFalseFromVariable(): void
 
     public function testDoesNotDeferWithSkipTrue(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo @defer @skip(if: true)
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [],
         ]);
     }
 
     public function testDoesDeferWithSkipFalse(): void
     {
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo @defer @skip(if: false)
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
     }
 
     public function testDoesNotDeferWithSkipTrueFromVariable(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($skip: Boolean!) {
             foo @defer @skip(if: $skip)
         }
-        ', [
+        GRAPHQL, [
             'skip' => true,
         ])->assertExactJson([
             'data' => [],
diff --git a/tests/Integration/Defer/DeferTest.php b/tests/Integration/Defer/DeferTest.php
index 5e90c9b6a0..44a603dc6d 100644
--- a/tests/Integration/Defer/DeferTest.php
+++ b/tests/Integration/Defer/DeferTest.php
@@ -28,7 +28,7 @@ protected function getPackageProviders($app): array
 
     public function testAddsTheDeferClientDirective(): void
     {
-        $introspection = $this->graphQL(/** @lang GraphQL */ '
+        $introspection = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query IntrospectionQuery {
           __schema {
             directives {
@@ -36,7 +36,7 @@ public function testAddsTheDeferClientDirective(): void
             }
           }
         }
-        ');
+        GRAPHQL);
 
         $this->assertContains(
             'defer',
@@ -53,7 +53,7 @@ public function testDeferFields(): void
             ],
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -62,9 +62,9 @@ public function testDeferFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -73,7 +73,7 @@ public function testDeferFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             [
@@ -110,7 +110,7 @@ public function testDeferNestedFields(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -119,9 +119,9 @@ public function testDeferNestedFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -133,7 +133,7 @@ public function testDeferNestedFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(3, $chunks);
 
@@ -160,7 +160,7 @@ public function testDeferNestedFieldsOnMutations(): void
             ],
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -173,9 +173,9 @@ public function testDeferNestedFieldsOnMutations(): void
         type Mutation {
             updateUser(name: String!): User @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(
                 name: "Foo"
@@ -186,7 +186,7 @@ public function testDeferNestedFieldsOnMutations(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             [
@@ -228,7 +228,7 @@ public function testDeferListFields(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             title: String
             author: User
@@ -241,9 +241,9 @@ public function testDeferListFields(): void
         type Query {
             posts: [Post] @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts {
                 title
@@ -252,7 +252,7 @@ public function testDeferListFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
 
@@ -290,7 +290,7 @@ public function testDeferGroupedListFields(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Comment {
             message: String
         }
@@ -308,9 +308,9 @@ public function testDeferGroupedListFields(): void
         type Query {
             posts: [Post] @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts {
                 title
@@ -322,7 +322,7 @@ public function testDeferGroupedListFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
 
@@ -357,7 +357,7 @@ public function testCancelsDefermentAfterMaxExecutionTime(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -366,14 +366,14 @@ public function testCancelsDefermentAfterMaxExecutionTime(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $defer = $this->app->make(Defer::class);
 
         // Set max execution time to now so we immediately resolve deferred fields
         $defer->setMaxExecutionTime(microtime(true));
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -385,7 +385,7 @@ public function testCancelsDefermentAfterMaxExecutionTime(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         // If we didn't hit the max execution time we would have 3 items in the array
         $this->assertCount(2, $chunks);
@@ -413,7 +413,7 @@ public function testCancelsDefermentAfterMaxNestedFields(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -422,13 +422,13 @@ public function testCancelsDefermentAfterMaxNestedFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $defer = $this->app->make(Defer::class);
 
         $defer->setMaxNestedFields(1);
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -440,7 +440,7 @@ public function testCancelsDefermentAfterMaxNestedFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
 
@@ -463,7 +463,7 @@ public function testThrowsExceptionOnNunNullableFields(): void
             ],
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User!
@@ -472,9 +472,9 @@ public function testThrowsExceptionOnNunNullableFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -483,7 +483,7 @@ public function testThrowsExceptionOnNunNullableFields(): void
                 }
             }
         }
-        ')->assertGraphQLErrorMessage(DeferrableDirective::THE_DEFER_DIRECTIVE_CANNOT_BE_USED_ON_A_NON_NULLABLE_FIELD);
+        GRAPHQL)->assertGraphQLErrorMessage(DeferrableDirective::THE_DEFER_DIRECTIVE_CANNOT_BE_USED_ON_A_NON_NULLABLE_FIELD);
     }
 
     public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
@@ -496,7 +496,7 @@ public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
             'skipped',
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         directive @include(if: Boolean!) on FIELD
         directive @skip(if: Boolean!) on FIELD
 
@@ -508,9 +508,9 @@ public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -519,7 +519,7 @@ public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => [
                     'name' => 'John Doe',
@@ -527,7 +527,7 @@ public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($include: Boolean!, $skip: Boolean!) {
             userInclude: user {
                 name
@@ -554,7 +554,7 @@ public function testDoesNotDeferWithIncludeAndSkipDirectives(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'include' => false,
             'skip' => true,
         ])->assertExactJson([
@@ -585,7 +585,7 @@ public function testRequiresDeferDirectiveOnAllFieldDeclarations(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -594,9 +594,9 @@ public function testRequiresDeferDirectiveOnAllFieldDeclarations(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         fragment UserWithParent on User {
             name
             parent {
@@ -611,7 +611,7 @@ public function testRequiresDeferDirectiveOnAllFieldDeclarations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => $data,
             ],
@@ -624,7 +624,7 @@ public function testThrowsIfTryingToDeferRootMutationFields(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -633,15 +633,15 @@ public function testThrowsIfTryingToDeferRootMutationFields(): void
         type Mutation {
             updateUser(name: String!): User @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation UpdateUser {
             updateUser(name: "John Doe") @defer {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(DeferrableDirective::THE_DEFER_DIRECTIVE_CANNOT_BE_USED_ON_A_ROOT_MUTATION_FIELD);
+        GRAPHQL)->assertGraphQLErrorMessage(DeferrableDirective::THE_DEFER_DIRECTIVE_CANNOT_BE_USED_ON_A_ROOT_MUTATION_FIELD);
     }
 
     public function testDoesNotDeferFieldsIfFalse(): void
@@ -654,7 +654,7 @@ public function testDoesNotDeferFieldsIfFalse(): void
         ];
         $this->mockResolver($data);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User
@@ -663,9 +663,9 @@ public function testDoesNotDeferFieldsIfFalse(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -674,7 +674,7 @@ public function testDoesNotDeferFieldsIfFalse(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => $data,
             ],
@@ -695,7 +695,7 @@ public function testIncludesErrorsForDeferredFields(): void
             'throw',
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             parent: User @mock(key: "throw")
@@ -704,9 +704,9 @@ public function testIncludesErrorsForDeferredFields(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
-        $chunks = $this->streamGraphQL(/** @lang GraphQL */ '
+        $chunks = $this->streamGraphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
@@ -715,7 +715,7 @@ public function testIncludesErrorsForDeferredFields(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertCount(2, $chunks);
 
diff --git a/tests/Integration/ErrorHandlersTest.php b/tests/Integration/ErrorHandlersTest.php
index c86f2fc4c4..de5dd173cc 100644
--- a/tests/Integration/ErrorHandlersTest.php
+++ b/tests/Integration/ErrorHandlersTest.php
@@ -17,17 +17,17 @@ public function testErrorHandlerReturningNull(): void
             throw new \Exception();
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => null,
             ],
diff --git a/tests/Integration/ErrorTest.php b/tests/Integration/ErrorTest.php
index ab42c1af2c..d137aa26ef 100644
--- a/tests/Integration/ErrorTest.php
+++ b/tests/Integration/ErrorTest.php
@@ -31,18 +31,19 @@ public function testRejectsEmptyRequest(): void
 
     public function testRejectsEmptyQuery(): void
     {
-        $this->graphQL('')
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+        GRAPHQL)
             ->assertStatus(200)
             ->assertGraphQLErrorMessage('GraphQL Request must include at least one of those two parameters: "query" or "queryId"');
     }
 
     public function testRejectsInvalidQuery(): void
     {
-        $result = $this->graphQL(/** @lang GraphQL */ '
-        {
-            nonExistingField
-        }
-        ');
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                {
+                    nonExistingField
+                }
+        GRAPHQL);
         $result->assertStatus(200);
 
         $this->assertStringContainsString(
@@ -61,17 +62,17 @@ public function testReturnsFullGraphQLError(bool $parseSourceLocations): void
         $message = 'some error';
         $this->mockResolver(static fn (): Error => new Error($message));
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $response = $this
             ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
-            {
-                foo
-            }
+                        {
+                            foo
+                        }
             GRAPHQL)
             ->assertStatus(200)
             ->assertJson([
@@ -108,7 +109,9 @@ public function testIgnoresInvalidJSONVariables(): void
     {
         $this
             ->postGraphQL([
-                'query' => /** @lang GraphQL */ '{}',
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
+                {}
+                GRAPHQL,
                 'variables' => '{}',
             ])
             ->assertStatus(200);
@@ -119,18 +122,18 @@ public function testHandlesErrorInResolver(): void
         $message = 'foo';
         $this->mockResolver(static fn () => throw new Error($message));
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             ->assertJson([
                 'data' => [
@@ -151,50 +154,50 @@ public function testRethrowsInternalExceptions(): void
 
         $this->mockResolver(static fn () => throw new \Exception('foo'));
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             ->assertJsonCount(1, 'errors');
 
         $config->set('lighthouse.debug', DebugFlag::RETHROW_INTERNAL_EXCEPTIONS);
 
         $this->expectException(\Exception::class);
-        $this->graphQL(/** @lang GraphQL */ '
-        {
-            foo
-        }
-        ');
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                {
+                    foo
+                }
+        GRAPHQL);
     }
 
     public function testReturnsMultipleErrors(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        input TestInput {
-            string: String!
-            integer: Int!
-        }
-
-        type Query {
-            foo(input: TestInput): ID
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input TestInput {
+                    string: String!
+                    integer: Int!
+                }
+        
+                type Query {
+                    foo(input: TestInput): ID
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(input: {})
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(input: {})
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             ->assertGraphQLErrorMessage('Field TestInput.string of required type String! was not provided.')
             ->assertGraphQLErrorMessage('Field TestInput.integer of required type Int! was not provided.');
@@ -205,12 +208,12 @@ public function testSplitsErrorsForMultipleOperations(): void
         $config = $this->app->make(ConfigRepository::class);
         $config->set('lighthouse.debug', DebugFlag::INCLUDE_DEBUG_MESSAGE);
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: Int
-            bar: String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: Int
+                    bar: String
+                }
+        GRAPHQL;
 
         $dispatcher = $this->app->make(EventsDispatcher::class);
         $dispatcher->listen(
@@ -221,19 +224,19 @@ public function testSplitsErrorsForMultipleOperations(): void
         $this
             ->postGraphQL([
                 [
-                    'query' => /** @lang GraphQL */ '
-                        query Foo {
-                            foo
-                        }
-                        ',
+                    'query' => /** @lang GraphQL */ <<<'GRAPHQL'
+                                            query Foo {
+                                                foo
+                                            }
+                    GRAPHQL,
                     'operationName' => 'Foo',
                 ],
                 [
-                    'query' => /** @lang GraphQL */ '
-                        query Bar {
-                            bar
-                        }
-                        ',
+                    'query' => /** @lang GraphQL */ <<<'GRAPHQL'
+                                            query Bar {
+                                                bar
+                                            }
+                    GRAPHQL,
                     'operationName' => 'Bar',
                 ],
             ])
@@ -274,19 +277,19 @@ public function testReturnsPartialDataIfNullableFieldFails(): void
         $error = new \Exception('fail');
         $this->mockResolver(static fn () => throw $error, 'fail');
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            success: Int! @mock(key: "success")
-            fail: Int @mock(key: "fail")
-        }
-        ';
-
-        $this->graphQL(/** @lang GraphQL */ '
-            {
-                success
-                fail
-            }
-            ')
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    success: Int! @mock(key: "success")
+                    fail: Int @mock(key: "fail")
+                }
+        GRAPHQL;
+
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                    {
+                        success
+                        fail
+                    }
+        GRAPHQL)
             ->assertStatus(200)
             ->assertJson([
                 'data' => [
@@ -308,19 +311,19 @@ public function testReturnsNoDataIfNonNullableFieldFails(): void
         $error = new \Exception('fail');
         $this->mockResolver(static fn () => throw $error, 'fail');
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            success: Int! @mock(key: "success")
-            fail: Int! @mock(key: "fail")
-        }
-        ';
-
-        $this->graphQL(/** @lang GraphQL */ '
-            {
-                success
-                fail
-            }
-            ')
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    success: Int! @mock(key: "success")
+                    fail: Int! @mock(key: "fail")
+                }
+        GRAPHQL;
+
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                    {
+                        success
+                        fail
+                    }
+        GRAPHQL)
             ->assertStatus(200)
             ->assertJsonMissingPath('data')
             ->assertGraphQLError($error);
@@ -328,18 +331,18 @@ public function testReturnsNoDataIfNonNullableFieldFails(): void
 
     public function testUnknownTypeInVariableDefinition(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(bar: ID): ID
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(bar: ID): ID
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            query ($bar: UnknownType) {
-                foo(bar: $bar)
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        query ($bar: UnknownType) {
+                            foo(bar: $bar)
+                        }
+            GRAPHQL)
             ->assertGraphQLErrorMessage('Unknown type "UnknownType".');
     }
 
@@ -352,18 +355,18 @@ public function testAssertGraphQLDebugMessage(): void
 
         $this->mockResolver(static fn () => throw new \Exception($message));
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             /** @see FormattedError::$internalErrorMessage */
             ->assertGraphQLErrorMessage('Internal server error')
@@ -376,18 +379,18 @@ public function testAssertGraphQLErrorClientSafe(): void
 
         $this->mockResolver(static fn () => throw $error);
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             ->assertGraphQLError($error);
     }
@@ -401,18 +404,18 @@ public function testAssertGraphQLErrorNonClientSafe(): void
 
         $this->mockResolver(static fn () => throw $exception);
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: ID @mock
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertStatus(200)
             /** @see FormattedError::$internalErrorMessage */
             ->assertGraphQLErrorMessage('Internal server error')
diff --git a/tests/Integration/Events/FieldDirective.php b/tests/Integration/Events/FieldDirective.php
index 3525b84d8a..e46ffb5e19 100644
--- a/tests/Integration/Events/FieldDirective.php
+++ b/tests/Integration/Events/FieldDirective.php
@@ -9,10 +9,10 @@ final class FieldDirective extends BaseDirective
     public static function definition(): string
     {
         return /** @lang GraphQL */ <<<'GRAPHQL'
-"""
-An alternate @field.
-"""
-directive @field on FIELD_DEFINITION
-GRAPHQL;
+        """
+        An alternate @field.
+        """
+        directive @field on FIELD_DEFINITION
+        GRAPHQL;
     }
 }
diff --git a/tests/Integration/Execution/ArgBuilderDirectiveTest.php b/tests/Integration/Execution/ArgBuilderDirectiveTest.php
index aae8966fee..1bb3ded777 100644
--- a/tests/Integration/Execution/ArgBuilderDirectiveTest.php
+++ b/tests/Integration/Execution/ArgBuilderDirectiveTest.php
@@ -8,19 +8,19 @@
 
 final class ArgBuilderDirectiveTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type User {
         id: ID!
         name: String
         email: String
     }
-    ';
+    GRAPHQL;
 
     public function testAttachNeqFilterToQuery(): void
     {
         $users = factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -28,19 +28,19 @@ public function testAttachNeqFilterToQuery(): void
         type Query {
             users(id: ID @neq): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user = $users->first();
         $this->assertInstanceOf(User::class, $user);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID) {
                 users(id: $id) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $user->id,
             ])
             ->assertJsonCount(2, 'data.users');
@@ -56,7 +56,7 @@ public function testAttachInFilterToQuery(): void
         $user2 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user2);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -64,16 +64,16 @@ public function testAttachInFilterToQuery(): void
         type Query {
             users(include: [Int] @in(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [Int]) {
                 users(include: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => [
                     $user1->id,
                     $user2->id,
@@ -92,7 +92,7 @@ public function testAttachNotInFilterToQuery(): void
         $user2 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user2);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -100,16 +100,16 @@ public function testAttachNotInFilterToQuery(): void
         type Query {
             users(exclude: [Int] @notIn(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [Int]) {
                 users(exclude: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => [
                     $user1->id,
                     $user2->id,
@@ -122,7 +122,7 @@ public function testAttachWhereFilterToQuery(): void
     {
         $users = factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -130,19 +130,19 @@ public function testAttachWhereFilterToQuery(): void
         type Query {
             users(id: Int @where(operator: ">")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user = $users->first();
         $this->assertInstanceOf(User::class, $user);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($userId: Int) {
                 users(id: $userId) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'userId' => $user->id,
             ])
             ->assertJsonCount(2, 'data.users');
@@ -152,7 +152,7 @@ public function testAttachTwoWhereFilterWithTheSameKeyToQuery(): void
     {
         factory(User::class, 5)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -163,9 +163,9 @@ public function testAttachTwoWhereFilterWithTheSameKeyToQuery(): void
                 end: Int @where(key: "id", operator: "<")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 start: 1
@@ -174,12 +174,12 @@ public function testAttachTwoWhereFilterWithTheSameKeyToQuery(): void
                 id
             }
         }
-        ')->assertJsonCount(3, 'data.users');
+        GRAPHQL)->assertJsonCount(3, 'data.users');
     }
 
     public function testAttachWhereBetweenFilterToQuery(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -189,7 +189,7 @@ public function testAttachWhereBetweenFilterToQuery(): void
                 createdBetween: [String!]! @whereBetween(key: "created_at")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
@@ -198,7 +198,7 @@ public function testAttachWhereBetweenFilterToQuery(): void
         $user->created_at = now()->subDay();
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($between: [String!]!) {
             users(
                 createdBetween: $between
@@ -206,7 +206,7 @@ public function testAttachWhereBetweenFilterToQuery(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'between' => [
                 now()->subDay()->startOfDay()->format('Y-m-d H:i:s'),
                 now()->subDay()->endOfDay()->format('Y-m-d H:i:s'),
@@ -216,7 +216,7 @@ public function testAttachWhereBetweenFilterToQuery(): void
 
     public function testUseInputObjectsForWhereBetweenFilter(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 created: TimeRange @whereBetween(key: "created_at")
@@ -227,7 +227,7 @@ public function testUseInputObjectsForWhereBetweenFilter(): void
             start: String!
             end: String!
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
@@ -236,7 +236,7 @@ public function testUseInputObjectsForWhereBetweenFilter(): void
         $user->created_at = now()->subDay();
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($start: String!, $end: String!) {
             users(
                 created: {
@@ -247,7 +247,7 @@ public function testUseInputObjectsForWhereBetweenFilter(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'start' => now()->subDay()->startOfDay()->format('Y-m-d H:i:s'),
             'end' => now()->subDay()->endOfDay()->format('Y-m-d H:i:s'),
         ])->assertJsonCount(1, 'data.users');
@@ -255,13 +255,13 @@ public function testUseInputObjectsForWhereBetweenFilter(): void
 
     public function testAttachWhereNotBetweenFilterToQuery(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 notCreatedBetween: [String!]! @whereNotBetween(key: "created_at")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
@@ -270,7 +270,7 @@ public function testAttachWhereNotBetweenFilterToQuery(): void
         $user->created_at = now()->subDay();
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($between: [String!]!) {
             users(
                 notCreatedBetween: $between
@@ -278,7 +278,7 @@ public function testAttachWhereNotBetweenFilterToQuery(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'between' => [
                 now()->subDay()->startOfDay()->format('Y-m-d H:i:s'),
                 now()->subDay()->endOfDay()->format('Y-m-d H:i:s'),
@@ -288,13 +288,13 @@ public function testAttachWhereNotBetweenFilterToQuery(): void
 
     public function testAttachWhereClauseFilterToQuery(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 created_at: String! @where(clause: "whereYear")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
@@ -305,68 +305,68 @@ public function testAttachWhereClauseFilterToQuery(): void
         $user->created_at = $oneYearAgo;
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($created_at: String!) {
             users(created_at: $created_at) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'created_at' => $oneYearAgo->format('Y'),
         ])->assertJsonCount(1, 'data.users');
     }
 
     public function testOnlyProcessesFilledArguments(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 id: ID @eq
                 name: String @where(operator: "like")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $users = factory(User::class, 3)->create();
 
         $user = $users->first();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($name: String) {
             users(name: $name) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'name' => $user->name,
         ])->assertJsonCount(1, 'data.users');
     }
 
     public function testDoesNotProcessUnusedVariable(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 ids: [ID!] @in
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($ids: [ID!]) {
             users(ids: $ids) {
                 id
             }
         }
-        ')->assertJsonCount(3, 'data.users');
+        GRAPHQL)->assertJsonCount(3, 'data.users');
     }
 
     public function testAttachMultipleWhereFiltersToQuery(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts(
                 content: String
@@ -378,7 +378,7 @@ public function testAttachMultipleWhereFiltersToQuery(): void
         type Post {
             id: Int!
         }
-        ';
+        GRAPHQL;
 
         $content = 'foo';
 
@@ -399,13 +399,13 @@ public function testAttachMultipleWhereFiltersToQuery(): void
         $titleAndBody->save();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($content: String) {
                 posts(content: $content) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'content' => $content,
             ])
             ->assertExactJson([
diff --git a/tests/Integration/Execution/DataLoader/RelationBatchLoaderTest.php b/tests/Integration/Execution/DataLoader/RelationBatchLoaderTest.php
index be3066f249..5d7eff84dc 100644
--- a/tests/Integration/Execution/DataLoader/RelationBatchLoaderTest.php
+++ b/tests/Integration/Execution/DataLoader/RelationBatchLoaderTest.php
@@ -17,7 +17,7 @@ final class RelationBatchLoaderTest extends DBTestCase
 {
     public function testResolveBatchedFieldsFromBatchedRequests(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -29,7 +29,7 @@ public function testResolveBatchedFieldsFromBatchedRequests(): void
         type Query {
             user(id: ID! @eq): User @find
         }
-        ';
+        GRAPHQL;
 
         $userCount = 2;
         $tasksPerUser = 3;
@@ -41,7 +41,7 @@ public function testResolveBatchedFieldsFromBatchedRequests(): void
                 );
             });
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         query User($id: ID!) {
             user(id: $id) {
                 tasks {
@@ -49,7 +49,7 @@ public function testResolveBatchedFieldsFromBatchedRequests(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $this
             ->postGraphQL([
@@ -75,7 +75,7 @@ public function testResolveBatchedFieldsFromBatchedRequests(): void
     #[DataProvider('batchloadRelationsSetting')]
     public function testBatchloadRelations(bool $batchloadRelations, int $expectedQueryCount): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -87,7 +87,7 @@ public function testBatchloadRelations(bool $batchloadRelations, int $expectedQu
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $userCount = 2;
         $tasksPerUser = 3;
@@ -103,7 +103,7 @@ public function testBatchloadRelations(bool $batchloadRelations, int $expectedQu
 
         $this->assertQueryCountMatches($expectedQueryCount, function () use ($userCount, $tasksPerUser): void {
             $this
-                ->graphQL(/** @lang GraphQL */ '
+                ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 {
                     users {
                         tasks {
@@ -111,7 +111,7 @@ public function testBatchloadRelations(bool $batchloadRelations, int $expectedQu
                         }
                     }
                 }
-                ')
+                GRAPHQL)
                 ->assertJsonCount($userCount, 'data.users')
                 ->assertJsonCount($tasksPerUser, 'data.users.0.tasks')
                 ->assertJsonCount($tasksPerUser, 'data.users.1.tasks');
@@ -120,7 +120,7 @@ public function testBatchloadRelations(bool $batchloadRelations, int $expectedQu
 
     public function testDoesNotBatchloadRelationsWithDifferentDatabaseConnections(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type AlternateConnection {
             id: ID
         }
@@ -132,7 +132,7 @@ public function testDoesNotBatchloadRelationsWithDifferentDatabaseConnections():
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $userCount = 2;
         $alternateConnectionsPerUser = 3;
@@ -147,7 +147,7 @@ public function testDoesNotBatchloadRelationsWithDifferentDatabaseConnections():
         $this->countQueries($queryCount);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     alternateConnections {
@@ -155,7 +155,7 @@ public function testDoesNotBatchloadRelationsWithDifferentDatabaseConnections():
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount($userCount, 'data.users')
             ->assertJsonCount($alternateConnectionsPerUser, 'data.users.0.alternateConnections')
             ->assertJsonCount($alternateConnectionsPerUser, 'data.users.1.alternateConnections');
@@ -165,7 +165,7 @@ public function testDoesNotBatchloadRelationsWithDifferentDatabaseConnections():
 
     public function testDoesNotBatchloadRelationsWithNullDatabaseConnections(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type NullConnection {
             users: [User!]! @hasMany
         }
@@ -177,7 +177,7 @@ public function testDoesNotBatchloadRelationsWithNullDatabaseConnections(): void
         type Query {
             nullConnections: [NullConnection!]! @all
         }
-        ';
+        GRAPHQL;
 
         $nullConnectionsCount = 2;
         $usersPerNullConnection = 3;
@@ -193,7 +193,7 @@ public function testDoesNotBatchloadRelationsWithNullDatabaseConnections(): void
 
         $this->assertQueryCountMatches(2, function () use ($nullConnectionsCount, $usersPerNullConnection): void {
             $this
-                ->graphQL(/** @lang GraphQL */ '
+                ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 {
                     nullConnections {
                         users {
@@ -201,7 +201,7 @@ public function testDoesNotBatchloadRelationsWithNullDatabaseConnections(): void
                         }
                     }
                 }
-                ')
+                GRAPHQL)
                 ->assertJsonCount($nullConnectionsCount, 'data.nullConnections')
                 ->assertJsonCount($usersPerNullConnection, 'data.nullConnections.0.users')
                 ->assertJsonCount($usersPerNullConnection, 'data.nullConnections.1.users');
@@ -217,7 +217,7 @@ public static function batchloadRelationsSetting(): iterable
 
     public function testCombineEagerLoadsThatAreTheSame(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -230,12 +230,12 @@ public function testCombineEagerLoadsThatAreTheSame(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     tasks {
@@ -243,21 +243,21 @@ public function testCombineEagerLoadsThatAreTheSame(): void
                     }
                 }
             }
-            ');
+            GRAPHQL);
         });
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     name
                 }
             }
-            ');
+            GRAPHQL);
         });
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     name
@@ -266,13 +266,13 @@ public function testCombineEagerLoadsThatAreTheSame(): void
                     }
                 }
             }
-            ');
+            GRAPHQL);
         });
     }
 
     public function testSplitsEagerLoadsByScopes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -285,12 +285,12 @@ public function testSplitsEagerLoadsByScopes(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
         $this->assertQueryCountMatches(3, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     name
@@ -299,13 +299,13 @@ public function testSplitsEagerLoadsByScopes(): void
                     }
                 }
             }
-            ');
+            GRAPHQL);
         });
     }
 
     public function testSplitsEagerLoadsWithArguments(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -318,12 +318,12 @@ public function testSplitsEagerLoadsWithArguments(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)->create();
 
         $this->assertQueryCountMatches(3, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     name
@@ -332,13 +332,13 @@ public function testSplitsEagerLoadsWithArguments(): void
                     }
                 }
             }
-            ');
+            GRAPHQL);
         });
     }
 
     public function testTwoBatchLoadedQueriesWithDifferentResults(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
         }
@@ -350,7 +350,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
         type Query {
             user(id: ID! @eq): User @find
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 2)
             ->create()
@@ -361,7 +361,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
             });
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: 1) {
                     tasks {
@@ -369,7 +369,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'user' => [
@@ -389,7 +389,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: 2) {
                     tasks {
@@ -397,7 +397,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'user' => [
@@ -420,7 +420,7 @@ public function testTwoBatchLoadedQueriesWithDifferentResults(): void
     /** @return never */
     public function testCombineEagerLoadsThatAreTheSameRecursively(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             task(id: Int! @eq): Task @find
         }
@@ -437,7 +437,7 @@ public function testCombineEagerLoadsThatAreTheSameRecursively(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -456,7 +456,7 @@ public function testCombineEagerLoadsThatAreTheSameRecursively(): void
         $this->countQueries($queryCount);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: Int!) {
                 task(id: $id) {
                     name
@@ -467,7 +467,7 @@ public function testCombineEagerLoadsThatAreTheSameRecursively(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $task->id,
             ])
             ->assertJson([
@@ -491,7 +491,7 @@ public function testCombineEagerLoadsThatAreTheSameRecursively(): void
 
     public function testBatchLoaderWithExpiredCacheEntry(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts: [Post!]! @all @cache(maxAge: 20)
         }
@@ -509,7 +509,7 @@ public function testBatchLoaderWithExpiredCacheEntry(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
         $user1 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user1);
@@ -539,7 +539,7 @@ public function testBatchLoaderWithExpiredCacheEntry(): void
             $comment->save();
         }
 
-        $firstRequest = $this->graphQL(/** @lang GraphQL */ '
+        $firstRequest = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query {
             posts {
                 comments {
@@ -549,7 +549,7 @@ public function testBatchLoaderWithExpiredCacheEntry(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         Cache::forget(
             (new CacheKeyAndTagsGenerator())->key(
@@ -563,7 +563,7 @@ public function testBatchLoaderWithExpiredCacheEntry(): void
             ),
         );
 
-        $secondRequest = $this->graphQL(/** @lang GraphQL */ '
+        $secondRequest = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query {
             posts {
                 comments {
@@ -573,7 +573,7 @@ public function testBatchLoaderWithExpiredCacheEntry(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame($firstRequest->json(), $secondRequest->json());
     }
diff --git a/tests/Integration/Execution/DataLoader/RelationCountBatchLoaderTest.php b/tests/Integration/Execution/DataLoader/RelationCountBatchLoaderTest.php
index 2473edd9b5..d5d2d96dc5 100644
--- a/tests/Integration/Execution/DataLoader/RelationCountBatchLoaderTest.php
+++ b/tests/Integration/Execution/DataLoader/RelationCountBatchLoaderTest.php
@@ -20,7 +20,7 @@ public function testResolveBatchedCountsFromBatchedRequests(): void
                 });
             });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID
             name: String
@@ -37,15 +37,15 @@ public function testResolveBatchedCountsFromBatchedRequests(): void
             user(id: ID! @eq): User @find
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 tasks_count
             }
         }
-        ';
+        GRAPHQL;
 
         $this
             ->postGraphQL([
diff --git a/tests/Integration/Execution/FieldBuilderDirectiveTest.php b/tests/Integration/Execution/FieldBuilderDirectiveTest.php
index b236351053..2ad8a1a898 100644
--- a/tests/Integration/Execution/FieldBuilderDirectiveTest.php
+++ b/tests/Integration/Execution/FieldBuilderDirectiveTest.php
@@ -9,21 +9,21 @@
 
 final class FieldBuilderDirectiveTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Post {
         id: Int!
     }
-    ';
+    GRAPHQL;
 
     public function testLimitPostByAuthenticatedUser(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts: [Post!]!
                 @all
                 @whereAuth(relation: "user")
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -36,13 +36,13 @@ public function testLimitPostByAuthenticatedUser(): void
 
         $this->be($user);
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query {
             posts {
                 id
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             $ownedPosts->pluck('id')->all(),
@@ -52,7 +52,7 @@ public function testLimitPostByAuthenticatedUser(): void
 
     public function testChangeGuard(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts: [Post!]!
                 @all
@@ -61,7 +61,7 @@ public function testChangeGuard(): void
                     guards: ["web"]
                 )
         }
-        ';
+        GRAPHQL;
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
         $ownedPosts = factory(Post::class, 3)->make();
@@ -75,13 +75,13 @@ public function testChangeGuard(): void
         $authFactory->guard('web')->setUser($user);
 
         $response = $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query {
                 posts {
                     id
                 }
             }
-            ');
+            GRAPHQL);
 
         $this->assertSame(
             $ownedPosts->pluck('id')->all(),
diff --git a/tests/Integration/Execution/MutationExecutor/BelongsToManyTest.php b/tests/Integration/Execution/MutationExecutor/BelongsToManyTest.php
index 967935b8dd..e164f7b50f 100644
--- a/tests/Integration/Execution/MutationExecutor/BelongsToManyTest.php
+++ b/tests/Integration/Execution/MutationExecutor/BelongsToManyTest.php
@@ -10,7 +10,7 @@
 
 final class BelongsToManyTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Role {
         id: ID!
         name: String
@@ -106,11 +106,11 @@ final class BelongsToManyTest extends DBTestCase
         id: ID! # role ID
         meta: String
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testSyncWithoutDetaching(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "user1"
@@ -144,7 +144,7 @@ public function testSyncWithoutDetaching(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'id' => '1',
@@ -174,7 +174,7 @@ public function testSyncWithoutDetaching(): void
 
     public function testCreateWithNewBelongsToMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createRole(input: {
                 name: "foobar"
@@ -197,7 +197,7 @@ public function testCreateWithNewBelongsToMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createRole' => [
                     'id' => '1',
@@ -215,7 +215,7 @@ public function testCreateWithNewBelongsToMany(): void
 
     public function testUpsertWithBelongsToManyOnNonExistentData(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertRole(input: {
                 id: 1
@@ -241,7 +241,7 @@ public function testUpsertWithBelongsToManyOnNonExistentData(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertRole' => [
                     'id' => '1',
@@ -326,7 +326,7 @@ public function testCreateAndConnectWithBelongsToMany(): void
         $user->name = 'user_two';
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createRole(input: {
                 name: "foobar"
@@ -342,7 +342,7 @@ public function testCreateAndConnectWithBelongsToMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createRole' => [
                     'id' => '1',
@@ -374,7 +374,7 @@ public function testUpsertUsingCreationAndConnectWithBelongsToMany(): void
         $user->name = 'user_two';
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertRole(input: {
                 id: 1
@@ -391,7 +391,7 @@ public function testUpsertUsingCreationAndConnectWithBelongsToMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertRole' => [
                     'id' => '1',
@@ -418,7 +418,7 @@ public function testCreateWithBelongsToMany(): void
         $role->name = 'is_admin';
         $role->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateRole(input: {
                 id: 1
@@ -442,7 +442,7 @@ public function testCreateWithBelongsToMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateRole' => [
                     'id' => '1',
@@ -470,7 +470,7 @@ public function testAllowsNullOperations(): void
     {
         factory(Role::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateRole(input: {
                 id: 1
@@ -494,7 +494,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateRole' => [
                     'id' => '1',
@@ -512,7 +512,7 @@ public function testUpsertUsingCreationWithBelongsToMany(): void
         $role->name = 'is_admin';
         $role->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateRole(input: {
                 id: 1
@@ -538,7 +538,7 @@ public function testUpsertUsingCreationWithBelongsToMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateRole' => [
                     'id' => '1',
@@ -830,7 +830,7 @@ public function testSyncExistingUsersDuringCreateToABelongsToManyRelation(): voi
     {
         factory(User::class, 2)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createRole(input: {
                 name: "foobar"
@@ -845,7 +845,7 @@ public function testSyncExistingUsersDuringCreateToABelongsToManyRelation(): voi
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createRole' => [
                     'id' => '1',
@@ -867,7 +867,7 @@ public function testSyncExistingUsersDuringCreateUsingUpsertToABelongsToManyRela
     {
         factory(User::class, 2)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertRole(input: {
                 id: 1
@@ -883,7 +883,7 @@ public function testSyncExistingUsersDuringCreateUsingUpsertToABelongsToManyRela
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertRole' => [
                     'id' => '1',
@@ -914,7 +914,7 @@ public function testDisconnectAllRelatedModelsOnEmptySync(string $action): void
 
         $this->assertCount(1, $role->users);
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         mutation {
             {$action}Role(input: {
                 id: 1
@@ -929,7 +929,7 @@ public function testDisconnectAllRelatedModelsOnEmptySync(string $action): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 "{$action}Role" => [
                     'id' => '1',
@@ -955,7 +955,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingSync(): void
 
         $meta = Lorem::sentence();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($meta: String) {
             pivotsUpdateUser(input: {
                 id: 1,
@@ -979,7 +979,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingSync(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'meta' => $meta,
         ])->assertJson([
             'data' => [
@@ -1014,7 +1014,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingSyncWithoutDetach(): v
 
         $meta = Lorem::sentence();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($meta: String) {
             pivotsUpdateUser(input: {
                 id: 1,
@@ -1034,7 +1034,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingSyncWithoutDetach(): v
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'meta' => $meta,
         ])->assertJson([
             'data' => [
@@ -1063,7 +1063,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingConnect(): void
 
         $meta = Lorem::sentence();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($meta: String) {
             pivotsUpdateUser(input: {
                 id: 1,
@@ -1083,7 +1083,7 @@ public function testConnectUserWithRoleAndPivotMetaByUsingConnect(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'meta' => $meta,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Execution/MutationExecutor/BelongsToTest.php b/tests/Integration/Execution/MutationExecutor/BelongsToTest.php
index 65f56e4721..660a9f4575 100644
--- a/tests/Integration/Execution/MutationExecutor/BelongsToTest.php
+++ b/tests/Integration/Execution/MutationExecutor/BelongsToTest.php
@@ -12,7 +12,7 @@
 
 final class BelongsToTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID!
         name: String!
@@ -81,14 +81,14 @@ final class BelongsToTest extends DBTestCase
         disconnect: Boolean
         delete: Boolean
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateAndConnectWithBelongsTo(): void
     {
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -103,7 +103,7 @@ public function testCreateAndConnectWithBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -118,7 +118,7 @@ public function testCreateAndConnectWithBelongsTo(): void
 
     public function testBelongsToExplicitNullHasNoEffect(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -131,7 +131,7 @@ public function testBelongsToExplicitNullHasNoEffect(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -147,7 +147,7 @@ public function testUpsertUsingCreateAndConnectWithBelongsTo(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -163,7 +163,7 @@ public function testUpsertUsingCreateAndConnectWithBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -181,7 +181,7 @@ public function testAllowsNullOperations(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -202,7 +202,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -215,7 +215,7 @@ public function testAllowsNullOperations(): void
 
     public function testCreateWithNewBelongsTo(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -232,7 +232,7 @@ public function testCreateWithNewBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -247,7 +247,7 @@ public function testCreateWithNewBelongsTo(): void
 
     public function testUpsertWithNewBelongsTo(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -265,7 +265,7 @@ public function testUpsertWithNewBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -345,7 +345,7 @@ public function testUpsertBelongsToWithIDNull(): void
 
     public function testUpsertUsingCreateWithNewBelongsTo(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -363,7 +363,7 @@ public function testUpsertUsingCreateWithNewBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -378,7 +378,7 @@ public function testUpsertUsingCreateWithNewBelongsTo(): void
 
     public function testUpsertUsingCreateWithNewUpsertBelongsTo(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -397,7 +397,7 @@ public function testUpsertUsingCreateWithNewUpsertBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -417,7 +417,7 @@ public function testCreateAndUpdateBelongsTo(): void
         $user->name = 'foo';
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -436,7 +436,7 @@ public function testCreateAndUpdateBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -457,7 +457,7 @@ public function testUpsertUsingCreateAndUpdateBelongsTo(): void
         $user->name = 'foo';
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -477,7 +477,7 @@ public function testUpsertUsingCreateAndUpdateBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -494,7 +494,7 @@ public function testUpsertUsingCreateAndUpdateBelongsTo(): void
     /** @see https://github.com/nuwave/lighthouse/pull/2570 */
     public function testSavesOnlyOnceWithMultipleBelongsTo(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User! @update
         }
@@ -540,7 +540,7 @@ public function testSavesOnlyOnceWithMultipleBelongsTo(): void
             id: ID!
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $user = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user);
@@ -554,7 +554,7 @@ public function testSavesOnlyOnceWithMultipleBelongsTo(): void
             $queries[] = $query->sql;
         });
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -584,7 +584,7 @@ public function testSavesOnlyOnceWithMultipleBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'id' => '1',
@@ -612,7 +612,7 @@ public function testUpsertUsingCreateAndUpdateUsingUpsertBelongsTo(): void
         $user->name = 'foo';
         $user->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -632,7 +632,7 @@ public function testUpsertUsingCreateAndUpdateUsingUpsertBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -678,7 +678,7 @@ public function testUpdateAndDisconnectBelongsTo(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}Task" => [
@@ -708,7 +708,7 @@ public function testCreateUsingUpsertAndDisconnectBelongsTo(): void
         $task->user()->associate($user);
         $task->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -724,7 +724,7 @@ public function testCreateUsingUpsertAndDisconnectBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -774,7 +774,7 @@ public function testUpdateAndDeleteBelongsTo(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}Task" => [
@@ -802,7 +802,7 @@ public function testCreateUsingUpsertAndDeleteBelongsTo(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -818,7 +818,7 @@ public function testCreateUsingUpsertAndDeleteBelongsTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -868,7 +868,7 @@ public function testDoesNotDeleteOrDisconnectOnFalsyValues(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}Task" => [
@@ -895,7 +895,7 @@ public function testDoesNotDeleteOrDisconnectOnFalsyValues(string $action): void
 
     public function testUpsertAcrossTwoNestedBelongsToRelations(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
             roles: [Role!] @belongsToMany
@@ -929,9 +929,9 @@ public function testUpsertAcrossTwoNestedBelongsToRelations(): void
         input UpsertRoleInput {
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 name: "foo"
@@ -951,7 +951,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'name' => 'foo',
@@ -967,7 +967,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelations(): void
 
     public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -1011,10 +1011,10 @@ public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingMo
         input UpsertRoleUsersRelation {
             sync: [ID!]
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         // Create the first User with a Role.
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 name: "foo"
@@ -1036,7 +1036,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingMo
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -1059,7 +1059,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingMo
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 id: "1"
@@ -1087,7 +1087,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingMo
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -1102,7 +1102,7 @@ public function testUpsertAcrossTwoNestedBelongsToRelationsAndOverrideExistingMo
 
     public function testCreateMultipleBelongsToThatDontExistYet(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type RoleUserPivot {
             id: ID!
             user: User!
@@ -1148,9 +1148,9 @@ public function testCreateMultipleBelongsToThatDontExistYet(): void
             id: ID!
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createRoleUser(input: {
                 id: "1"
@@ -1178,7 +1178,7 @@ public function testCreateMultipleBelongsToThatDontExistYet(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createRoleUser' => [
                     'id' => '1',
@@ -1197,7 +1197,7 @@ public function testCreateMultipleBelongsToThatDontExistYet(): void
 
     public function testCreateMultipleBelongsToThatDontExistYetWithExistingRecords(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type RoleUserPivot {
             id: ID!
             meta: String
@@ -1245,9 +1245,9 @@ public function testCreateMultipleBelongsToThatDontExistYetWithExistingRecords()
             id: ID
             name: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createRoleUser(input: {
                 meta: "asdf"
@@ -1273,7 +1273,8 @@ public function testCreateMultipleBelongsToThatDontExistYetWithExistingRecords()
                     name
                 }
             }
-        }';
+        }
+        GRAPHQL;
 
         // This must first create a user, then a role, then attach them to the pivot
         $this->graphQL($query)->assertJson([
diff --git a/tests/Integration/Execution/MutationExecutor/HasManyTest.php b/tests/Integration/Execution/MutationExecutor/HasManyTest.php
index a66bed5c47..bf564e1de9 100644
--- a/tests/Integration/Execution/MutationExecutor/HasManyTest.php
+++ b/tests/Integration/Execution/MutationExecutor/HasManyTest.php
@@ -11,7 +11,7 @@
 
 final class HasManyTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID!
         name: String!
@@ -83,11 +83,11 @@ final class HasManyTest extends DBTestCase
         id: ID
         name: String
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateWithNewHasMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -107,7 +107,7 @@ public function testCreateWithNewHasMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'id' => '1',
@@ -131,7 +131,7 @@ public function testCreateWithConnectHasMany(): void
         $task2 = factory(Task::class)->create();
         $this->assertInstanceOf(Task::class, $task2);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: CreateUserInput!) {
                 createUser(input: $input) {
                     name
@@ -141,7 +141,7 @@ public function testCreateWithConnectHasMany(): void
                     }
                 }
             }
-            ',
+        GRAPHQL,
             [
                 'input' => [
                     'name' => 'foo',
@@ -176,7 +176,7 @@ public function testAllowsNullOperations(): void
     {
         factory(User::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -194,7 +194,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -206,7 +206,7 @@ public function testAllowsNullOperations(): void
 
     public function testUpsertWithNewHasMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -225,7 +225,7 @@ public function testUpsertWithNewHasMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'id' => '1',
@@ -243,7 +243,7 @@ public function testUpsertWithNewHasMany(): void
 
     public function testUpsertHasManyWithoutId(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 name: "foo"
@@ -261,7 +261,7 @@ public function testUpsertHasManyWithoutId(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -279,7 +279,7 @@ public function testUpsertHasManyWithoutId(): void
 
     public function testCreateUsingUpsertWithNewHasMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 id: 1
@@ -299,7 +299,7 @@ public function testCreateUsingUpsertWithNewHasMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -443,7 +443,7 @@ public function testUpsertHasMany(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}User" => [
@@ -489,7 +489,7 @@ public function testDeleteHasMany(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}User" => [
@@ -516,7 +516,7 @@ public function testConnectHasMany(string $action): void
 
         $actionInputName = ucfirst($action);
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
             mutation (\$input: {$actionInputName}UserInput!) {
                 {$action}User(input: \$input) {
                     id
@@ -527,7 +527,7 @@ public function testConnectHasMany(string $action): void
                     }
                 }
             }
-            ",
+        GRAPHQL,
             [
                 'input' => [
                     'id' => $user->id,
@@ -578,7 +578,7 @@ public function testDisconnectHasMany(string $action): void
 
         $actionInputName = ucfirst($action);
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
             mutation (\$input: {$actionInputName}UserInput!) {
                 {$action}User(input: \$input) {
                     id
@@ -589,7 +589,7 @@ public function testDisconnectHasMany(string $action): void
                     }
                 }
             }
-        ", [
+        GRAPHQL, [
             'input' => [
                 'id' => $user->id,
                 'name' => 'foo',
@@ -619,7 +619,7 @@ public function testDisconnectHasMany(string $action): void
 
     public function testUpsertAcrossPivotTableOverrideExistingModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -654,10 +654,10 @@ public function testUpsertAcrossPivotTableOverrideExistingModel(): void
         input UpsertRoleUsersRelation {
             sync: [ID!]
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         // Create the first User with a Role.
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 name: "foo"
@@ -675,7 +675,7 @@ public function testUpsertAcrossPivotTableOverrideExistingModel(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -697,7 +697,7 @@ public function testUpsertAcrossPivotTableOverrideExistingModel(): void
         // Create another User.
         factory(User::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 id: "1"
@@ -720,7 +720,7 @@ public function testUpsertAcrossPivotTableOverrideExistingModel(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => '1',
@@ -735,7 +735,7 @@ public function testUpsertAcrossPivotTableOverrideExistingModel(): void
 
     public function testConnectModelWithCustomKey(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -771,11 +771,11 @@ public function testConnectModelWithCustomKey(): void
             connect: [ID!]
             disconnect: [ID!]
         }
-        ';
+        GRAPHQL;
 
         factory(CustomPrimaryKey::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation {
                 createUser(input: {
                     name: "foo"
@@ -790,7 +790,7 @@ public function testConnectModelWithCustomKey(): void
                     }
                 }
             }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'id' => '1',
@@ -810,7 +810,7 @@ public function testConnectModelWithCustomKey(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation {
                 updateUser(input: {
                     id: "1"
@@ -826,7 +826,7 @@ public function testConnectModelWithCustomKey(): void
                     }
                 }
             }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'id' => '1',
@@ -849,7 +849,7 @@ public function testUpdateNestedHasMany(): void
         $task = factory(Task::class)->create();
         $this->assertInstanceOf(Task::class, $task);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: UpdateUserInput!) {
                 updateUser(input: $input) {
                     id
@@ -860,7 +860,7 @@ public function testUpdateNestedHasMany(): void
                     }
                 }
             }
-           ', [
+        GRAPHQL, [
             'input' => [
                 'id' => $user->id,
                 'name' => 'foo',
diff --git a/tests/Integration/Execution/MutationExecutor/HasOneTest.php b/tests/Integration/Execution/MutationExecutor/HasOneTest.php
index 3780e60abd..b6856e22c7 100644
--- a/tests/Integration/Execution/MutationExecutor/HasOneTest.php
+++ b/tests/Integration/Execution/MutationExecutor/HasOneTest.php
@@ -9,7 +9,7 @@
 
 final class HasOneTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID!
         name: String!
@@ -77,11 +77,11 @@ final class HasOneTest extends DBTestCase
         id: ID
         title: String
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateWithNewHasOne(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -99,7 +99,7 @@ public function testCreateWithNewHasOne(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -115,7 +115,7 @@ public function testCreateWithNewHasOne(): void
 
     public function testUpsertWithNewHasOne(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -134,7 +134,7 @@ public function testUpsertWithNewHasOne(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -150,7 +150,7 @@ public function testUpsertWithNewHasOne(): void
 
     public function testCreateUsingUpsertWithNewHasOne(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 2
@@ -170,7 +170,7 @@ public function testCreateUsingUpsertWithNewHasOne(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '2',
@@ -186,7 +186,7 @@ public function testCreateUsingUpsertWithNewHasOne(): void
 
     public function testUpsertHasOneWithoutID(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 name: "foo"
@@ -204,7 +204,7 @@ public function testUpsertHasOneWithoutID(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -220,7 +220,7 @@ public function testUpsertHasOneWithoutID(): void
 
     public function testUpsertHasOneWithIDNull(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 name: "foo"
@@ -239,7 +239,7 @@ public function testUpsertHasOneWithIDNull(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
diff --git a/tests/Integration/Execution/MutationExecutor/MorphManyTest.php b/tests/Integration/Execution/MutationExecutor/MorphManyTest.php
index fdcb73ef13..497cd79de4 100644
--- a/tests/Integration/Execution/MutationExecutor/MorphManyTest.php
+++ b/tests/Integration/Execution/MutationExecutor/MorphManyTest.php
@@ -9,7 +9,7 @@
 
 final class MorphManyTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID!
         name: String!
@@ -81,11 +81,11 @@ final class MorphManyTest extends DBTestCase
         id: ID
         url: String
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateWithNewMorphMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -102,7 +102,7 @@ public function testCreateWithNewMorphMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -119,7 +119,7 @@ public function testCreateWithNewMorphMany(): void
 
     public function testCreateWithUpsertMorphMany(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -137,7 +137,7 @@ public function testCreateWithUpsertMorphMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -157,7 +157,7 @@ public function testCreateWithConnectMorphMany(): void
         $image1 = factory(Image::class)->create();
         $this->assertInstanceOf(Image::class, $image1);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation ($input: CreateTaskInput!) {
                 createTask(input: $input) {
                     id
@@ -167,7 +167,7 @@ public function testCreateWithConnectMorphMany(): void
                     }
                 }
             }
-        ', [
+        GRAPHQL, [
             'input' => [
                 'name' => 'foo',
                 'images' => [
@@ -192,7 +192,7 @@ public function testCreateWithConnectMorphMany(): void
 
     public function testUpsertMorphManyWithoutId(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 name: "foo"
@@ -210,7 +210,7 @@ public function testUpsertMorphManyWithoutId(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'id' => '1',
@@ -230,7 +230,7 @@ public function testAllowsNullOperations(): void
     {
         factory(Task::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateTask(input: {
                 id: 1
@@ -248,7 +248,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateTask' => [
                     'name' => 'foo',
@@ -289,7 +289,7 @@ public function testUpdateWithNewMorphMany(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}Task" => [
@@ -336,7 +336,7 @@ public function testUpdateAndUpdateMorphMany(string $action): void
                 }
             }
         }
-GRAPHQL
+        GRAPHQL,
         )->assertJson([
             'data' => [
                 "{$action}Task" => [
diff --git a/tests/Integration/Execution/MutationExecutor/MorphOneTest.php b/tests/Integration/Execution/MutationExecutor/MorphOneTest.php
index 5402b21914..915e287a39 100644
--- a/tests/Integration/Execution/MutationExecutor/MorphOneTest.php
+++ b/tests/Integration/Execution/MutationExecutor/MorphOneTest.php
@@ -9,7 +9,7 @@
 
 final class MorphOneTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID!
         name: String!
@@ -76,11 +76,11 @@ final class MorphOneTest extends DBTestCase
         id: ID
         url: String
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateWithNewMorphOne(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -97,7 +97,7 @@ public function testCreateWithNewMorphOne(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -112,7 +112,7 @@ public function testCreateWithNewMorphOne(): void
 
     public function testCreateWithUpsertMorphOne(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -130,7 +130,7 @@ public function testCreateWithUpsertMorphOne(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
@@ -181,7 +181,7 @@ public function testAllowsNullOperations(): void
     {
         factory(Task::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateTask(input: {
                 id: 1
@@ -199,7 +199,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateTask' => [
                     'name' => 'foo',
@@ -382,7 +382,7 @@ public function testNestedConnectMorphOne(): void
         $image = factory(Image::class)->create();
         $this->assertInstanceOf(Image::class, $image);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($input: UpdateTaskInput!) {
             updateTask(input: $input) {
                 id
@@ -392,7 +392,7 @@ public function testNestedConnectMorphOne(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'input' => [
                 'id' => $task->id,
                 'name' => 'foo',
diff --git a/tests/Integration/Execution/MutationExecutor/MorphToManyTest.php b/tests/Integration/Execution/MutationExecutor/MorphToManyTest.php
index 6a1bcd4885..2114e23f3b 100644
--- a/tests/Integration/Execution/MutationExecutor/MorphToManyTest.php
+++ b/tests/Integration/Execution/MutationExecutor/MorphToManyTest.php
@@ -7,7 +7,7 @@
 
 final class MorphToManyTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Mutation {
         createTask(input: CreateTaskInput! @spread): Task @create
         upsertTask(input: UpsertTaskInput! @spread): Task @upsert
@@ -57,7 +57,7 @@ final class MorphToManyTest extends DBTestCase
         id: ID!
         name: String!
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testCreateATaskWithExistingTagsByUsingConnect(): void
     {
@@ -66,7 +66,7 @@ public function testCreateATaskWithExistingTagsByUsingConnect(): void
         $tag->name = 'php';
         $tag->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "Finish tests"
@@ -79,7 +79,7 @@ public function testCreateATaskWithExistingTagsByUsingConnect(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'tags' => [
@@ -94,7 +94,7 @@ public function testCreateATaskWithExistingTagsByUsingConnect(): void
 
     public function testAllowsNullOperations(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "Finish tests"
@@ -111,7 +111,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'name' => 'Finish tests',
@@ -128,7 +128,7 @@ public function testUpsertATaskWithExistingTagsByUsingConnect(): void
         $tag->name = 'php';
         $tag->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -142,7 +142,7 @@ public function testUpsertATaskWithExistingTagsByUsingConnect(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'tags' => [
@@ -162,7 +162,7 @@ public function testCreateATaskWithExistingTagsByUsingSync(): void
         $tag->name = 'php';
         $tag->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "Finish tests"
@@ -175,7 +175,7 @@ public function testCreateATaskWithExistingTagsByUsingSync(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'tags' => [
@@ -195,7 +195,7 @@ public function testUpsertATaskWithExistingTagsByUsingSync(): void
         $tag->name = 'php';
         $tag->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -209,7 +209,7 @@ public function testUpsertATaskWithExistingTagsByUsingSync(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'tags' => [
@@ -224,7 +224,7 @@ public function testUpsertATaskWithExistingTagsByUsingSync(): void
 
     public function testCreateANewTagRelationByUsingCreate(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "Finish tests"
@@ -242,7 +242,7 @@ public function testCreateANewTagRelationByUsingCreate(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'tags' => [
@@ -258,7 +258,7 @@ public function testCreateANewTagRelationByUsingCreate(): void
 
     public function testUpsertANewTagRelationByUsingCreate(): void
     {
-        $this->graphQL('
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -277,7 +277,7 @@ public function testUpsertANewTagRelationByUsingCreate(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'tags' => [
@@ -293,7 +293,7 @@ public function testUpsertANewTagRelationByUsingCreate(): void
 
     public function testUpsertANewTagRelationByUsingUpsert(): void
     {
-        $this->graphQL('
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertTask(input: {
                 id: 1
@@ -313,7 +313,7 @@ public function testUpsertANewTagRelationByUsingUpsert(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertTask' => [
                     'tags' => [
diff --git a/tests/Integration/Execution/MutationExecutor/MorphToTest.php b/tests/Integration/Execution/MutationExecutor/MorphToTest.php
index 39202732b3..8e97a19039 100644
--- a/tests/Integration/Execution/MutationExecutor/MorphToTest.php
+++ b/tests/Integration/Execution/MutationExecutor/MorphToTest.php
@@ -12,7 +12,7 @@
 
 final class MorphToTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Task {
         id: ID
         name: String
@@ -90,7 +90,7 @@ final class MorphToTest extends DBTestCase
         disconnect: Boolean
         delete: Boolean
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testConnectsMorphTo(): void
     {
@@ -99,13 +99,13 @@ public function testConnectsMorphTo(): void
         $task->name = 'first_task';
         $task->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createImage(input: {
                 url: "foo"
                 imageable: {
                     connect: {
-                        type: "Tests\\\Utils\\\Models\\\Task"
+                        type: "Tests\\Utils\\Models\\Task"
                         id: 1
                     }
                 }
@@ -118,7 +118,7 @@ public function testConnectsMorphTo(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createImage' => [
                     'id' => '1',
@@ -147,7 +147,7 @@ public function testConnectsMorphToWithEnumType(): void
         $task->name = 'first_task';
         $task->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createImageWithEnumType(input: {
                 url: "foo"
@@ -166,7 +166,7 @@ public function testConnectsMorphToWithEnumType(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createImageWithEnumType' => [
                     'id' => '1',
@@ -187,14 +187,14 @@ public function testConnectsMorphToWithUpsert(): void
         $task->name = 'first_task';
         $task->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertImage(input: {
                 id: 1
                 url: "foo"
                 imageable: {
                     connect: {
-                        type: "Tests\\\Utils\\\Models\\\Task"
+                        type: "Tests\\Utils\\Models\\Task"
                         id: 1
                     }
                 }
@@ -207,7 +207,7 @@ public function testConnectsMorphToWithUpsert(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertImage' => [
                     'id' => '1',
@@ -225,7 +225,7 @@ public function testAllowsNullOperations(): void
     {
         factory(Image::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateImage(input: {
                 id: 1
@@ -242,7 +242,7 @@ public function testAllowsNullOperations(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateImage' => [
                     'url' => 'foo',
diff --git a/tests/Integration/Federation/FederationEntitiesModelTest.php b/tests/Integration/Federation/FederationEntitiesModelTest.php
index 69f0dcae0a..dc3b2a8356 100644
--- a/tests/Integration/Federation/FederationEntitiesModelTest.php
+++ b/tests/Integration/Federation/FederationEntitiesModelTest.php
@@ -20,11 +20,11 @@ protected function getPackageProviders($app): array
 
     public function testCallsEntityResolverModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User @key(fields: "id") {
           id: ID! @external
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
 
@@ -33,7 +33,7 @@ public function testCallsEntityResolverModel(): void
             'id' => (string) $user->getKey(),
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -42,7 +42,7 @@ public function testCallsEntityResolverModel(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $userRepresentation,
             ],
@@ -57,7 +57,7 @@ public function testCallsEntityResolverModel(): void
 
     public function testCallsNestedEntityResolverModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User @key(fields: "company { id }") {
           id: ID! @external
           company: Company! @belongsTo
@@ -66,7 +66,7 @@ public function testCallsNestedEntityResolverModel(): void
         type Company {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
         $company = factory(Company::class)->create();
         $this->assertInstanceOf(Company::class, $company);
@@ -84,7 +84,7 @@ public function testCallsNestedEntityResolverModel(): void
             ],
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -93,7 +93,7 @@ public function testCallsNestedEntityResolverModel(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $userRepresentation,
             ],
@@ -111,11 +111,11 @@ public function testCallsNestedEntityResolverModel(): void
 
     public function testCallsEntityResolverModelWithGlobalId(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User @key(fields: "id") {
           id: ID! @external @globalId
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
 
@@ -124,7 +124,7 @@ public function testCallsEntityResolverModelWithGlobalId(): void
             'id' => $this->app->get(GlobalId::class)->encode('User', $user->getKey()),
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -133,7 +133,7 @@ public function testCallsEntityResolverModelWithGlobalId(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $userRepresentation,
             ],
@@ -148,12 +148,12 @@ public function testCallsEntityResolverModelWithGlobalId(): void
 
     public function testHydratesExternalFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User @key(fields: "id") {
           id: ID!
           externallyProvided: String! @external
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -164,7 +164,7 @@ public function testHydratesExternalFields(): void
             'externallyProvided' => 'some value that we know nothing about',
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -174,7 +174,7 @@ public function testHydratesExternalFields(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $userRepresentation,
             ],
diff --git a/tests/Integration/Federation/FederationEntitiesTest.php b/tests/Integration/Federation/FederationEntitiesTest.php
index 7197d2022b..4bcc7e141f 100644
--- a/tests/Integration/Federation/FederationEntitiesTest.php
+++ b/tests/Integration/Federation/FederationEntitiesTest.php
@@ -21,7 +21,7 @@ protected function getPackageProviders($app): array
 
     public function testCallsEntityResolverClass(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
@@ -30,14 +30,14 @@ public function testCallsEntityResolverClass(): void
         type Query {
           foo: Int!
         }
-        ';
+        GRAPHQL;
 
         $foo = [
             '__typename' => 'Foo',
             'id' => '42',
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -46,7 +46,7 @@ public function testCallsEntityResolverClass(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $foo,
             ],
@@ -61,7 +61,7 @@ public function testCallsEntityResolverClass(): void
 
     public function testCallsBatchedEntityResolverClass(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type BatchedFoo @key(fields: "id") {
           id: ID! @external
           foo: String!
@@ -70,7 +70,7 @@ public function testCallsBatchedEntityResolverClass(): void
         type Query {
           foo: Int!
         }
-        ';
+        GRAPHQL;
 
         $foo1 = [
             '__typename' => 'BatchedFoo',
@@ -82,7 +82,7 @@ public function testCallsBatchedEntityResolverClass(): void
             'id' => '69',
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -91,7 +91,7 @@ public function testCallsBatchedEntityResolverClass(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $foo1,
                 $foo2,
@@ -109,7 +109,7 @@ public function testCallsBatchedEntityResolverClass(): void
     /** https://github.com/apollographql/apollo-federation-subgraph-compatibility/issues/70. */
     public function testMaintainsOrderOfRepresentationsInResult(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
@@ -123,7 +123,7 @@ public function testMaintainsOrderOfRepresentationsInResult(): void
         type Query {
           foo: Int!
         }
-        ';
+        GRAPHQL;
 
         $foo1 = [
             '__typename' => 'BatchedFoo',
@@ -140,7 +140,7 @@ public function testMaintainsOrderOfRepresentationsInResult(): void
             'id' => '9001',
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($representations: [_Any!]!) {
             _entities(representations: $representations) {
                 __typename
@@ -152,7 +152,7 @@ public function testMaintainsOrderOfRepresentationsInResult(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'representations' => [
                 $foo1,
                 $foo2,
@@ -171,14 +171,14 @@ public function testMaintainsOrderOfRepresentationsInResult(): void
 
     public function testThrowsWhenTypeIsUnknown(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -190,7 +190,7 @@ public function testThrowsWhenTypeIsUnknown(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             EntityResolverProvider::unknownTypename('Unknown'),
@@ -200,14 +200,14 @@ public function testThrowsWhenTypeIsUnknown(): void
 
     public function testThrowsWhenRepresentationIsNotArray(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -219,7 +219,7 @@ public function testThrowsWhenRepresentationIsNotArray(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             Any::isNotArray(),
@@ -229,14 +229,14 @@ public function testThrowsWhenRepresentationIsNotArray(): void
 
     public function testThrowsWhenTypeIsNotString(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -248,7 +248,7 @@ public function testThrowsWhenTypeIsNotString(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             Any::typenameIsNotString(),
@@ -258,17 +258,17 @@ public function testThrowsWhenTypeIsNotString(): void
 
     public function testThrowsWhenTypeIsInvalidName(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $isValidNameError = Utils::isValidNameError('1');
         $this->assertInstanceOf(Error::class, $isValidNameError);
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -280,7 +280,7 @@ public function testThrowsWhenTypeIsInvalidName(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             Any::typenameIsInvalidName($isValidNameError),
@@ -290,14 +290,14 @@ public function testThrowsWhenTypeIsInvalidName(): void
 
     public function testThrowsWhenNoKeySelectionIsSatisfied(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -309,7 +309,7 @@ public function testThrowsWhenNoKeySelectionIsSatisfied(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             'Representation does not satisfy any set of uniquely identifying keys',
@@ -319,14 +319,14 @@ public function testThrowsWhenNoKeySelectionIsSatisfied(): void
 
     public function testThrowsWhenMissingResolver(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type MissingResolver @key(fields: "id") {
           id: ID! @external
           foo: String!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _entities(
                 representations: [
@@ -341,7 +341,7 @@ public function testThrowsWhenMissingResolver(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertStringContainsString(
             EntityResolverProvider::missingResolver('MissingResolver'),
diff --git a/tests/Integration/Federation/FederationSchemaTest.php b/tests/Integration/Federation/FederationSchemaTest.php
index 36448390fa..0c5dc1311f 100644
--- a/tests/Integration/Federation/FederationSchemaTest.php
+++ b/tests/Integration/Federation/FederationSchemaTest.php
@@ -9,8 +9,8 @@
 final class FederationSchemaTest extends TestCase
 {
     private const FEDERATION_V2_SCHEMA_EXTENSION = /** @lang GraphQL */ <<<'GRAPHQL'
-    extend schema @link(url: "https://specs.apollo.dev/federation/v2.3", import: ["@composeDirective", "@extends", "@external", "@inaccessible", "@interfaceObject", "@key", "@override", "@provides", "@requires", "@shareable", "@tag"])
-    GRAPHQL;
+        extend schema @link(url: "https://specs.apollo.dev/federation/v2.3", import: ["@composeDirective", "@extends", "@external", "@inaccessible", "@interfaceObject", "@key", "@override", "@provides", "@requires", "@shareable", "@tag"])
+        GRAPHQL;
 
     protected function getPackageProviders($app): array
     {
@@ -57,12 +57,14 @@ public function testServiceQueryShouldReturnValidSdlWithoutQuery(): void
         $sdl = $this->_serviceSdl();
 
         $this->assertStringContainsString($typeFoo, $sdl);
-        $this->assertStringNotContainsString(/** @lang GraphQL */ 'type Query', $sdl);
+        $this->assertStringNotContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        type Query
+        GRAPHQL, $sdl);
     }
 
     public function testFederatedSchemaShouldContainCorrectEntityUnion(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID! @external
           foo: String!
@@ -76,7 +78,7 @@ public function testFederatedSchemaShouldContainCorrectEntityUnion(): void
         type Query {
           foo: Int!
         }
-        ');
+        GRAPHQL);
 
         $_Entity = $schema->getType('_Entity');
         $this->assertInstanceOf(UnionType::class, $_Entity);
@@ -175,13 +177,13 @@ public function testPaginationTypesAreMarkedAsSharableWhenUsingFederationV2(): v
 
     private function _serviceSdl(): string
     {
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             _service {
                 sdl
             }
         }
-        ');
+        GRAPHQL);
 
         return $response->json('data._service.sdl');
     }
diff --git a/tests/Integration/FieldMiddlewareTest.php b/tests/Integration/FieldMiddlewareTest.php
index 83c6998929..69d9394d68 100644
--- a/tests/Integration/FieldMiddlewareTest.php
+++ b/tests/Integration/FieldMiddlewareTest.php
@@ -10,7 +10,7 @@ final class FieldMiddlewareTest extends TestCase
 {
     public function testTransformsArgsBeforeCustomFieldMiddleware(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(id: ID! @trim): Foo @customFieldMiddleware
         }
@@ -18,15 +18,15 @@ public function testTransformsArgsBeforeCustomFieldMiddleware(): void
         type Foo {
             id: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(id: "   foo   ") {
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'id' => 'foo',
@@ -37,7 +37,7 @@ public function testTransformsArgsBeforeCustomFieldMiddleware(): void
 
     public function testFieldMiddlewareResolveInDefinitionOrder(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @guard
@@ -48,15 +48,15 @@ public function testFieldMiddlewareResolveInDefinitionOrder(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
     }
 
     public function testHydratesGlobalFieldMiddleware(): void
@@ -65,17 +65,17 @@ public function testHydratesGlobalFieldMiddleware(): void
             GlobalFieldMiddlewareDirective::class,
         ]]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Boolean
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => true,
             ],
diff --git a/tests/Integration/FileUploadTest.php b/tests/Integration/FileUploadTest.php
index c0b88548f9..e1de18a539 100644
--- a/tests/Integration/FileUploadTest.php
+++ b/tests/Integration/FileUploadTest.php
@@ -8,23 +8,23 @@
 
 final class FileUploadTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
-    scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
+    scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
     type Mutation {
         upload(file: Upload): Boolean
     }
-    ' . self::PLACEHOLDER_QUERY;
+    GRAPHQL . self::PLACEHOLDER_QUERY;
 
     /** https://github.com/jaydenseric/graphql-multipart-request-spec#single-file. */
     public function testResolvesUploadViaMultipartRequest(): void
     {
         $operations = [
-            'query' => /** @lang GraphQL */ '
+            'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     upload(file: $file)
                 }
-            ',
+            GRAPHQL,
             'variables' => [
                 'file' => null,
             ],
@@ -50,11 +50,11 @@ public function testResolvesUploadViaMultipartRequest(): void
     public function testUploadNull(): void
     {
         $operations = [
-            'query' => /** @lang GraphQL */ '
+            'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload) {
                     upload(file: $file)
                 }
-            ',
+            GRAPHQL,
             'variables' => [
                 'file' => null,
             ],
@@ -77,12 +77,12 @@ public function testUploadNull(): void
     public function testResolvesUploadViaBatchedMultipartRequest(): void
     {
         $operations = [
-            'query' => /** @lang GraphQL */ '
+            'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file1: Upload!, $file2: Upload!) {
                     first: upload(file: $file1)
                     second: upload(file: $file2)
                 }
-            ',
+            GRAPHQL,
             'variables' => [
                 'file1' => null,
                 'file2' => null,
diff --git a/tests/Integration/GlobalErrorRendererTest.php b/tests/Integration/GlobalErrorRendererTest.php
index 40395c8be5..776085c473 100644
--- a/tests/Integration/GlobalErrorRendererTest.php
+++ b/tests/Integration/GlobalErrorRendererTest.php
@@ -31,17 +31,17 @@ protected function resolveApplicationExceptionHandler($app): void
 
     public function testCatchesErrorWithExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'errors' => [
                 [
                     'message' => self::MESSAGE,
diff --git a/tests/Integration/GlobalId/NodeDirectiveDBTest.php b/tests/Integration/GlobalId/NodeDirectiveDBTest.php
index 60aff30853..0325473674 100644
--- a/tests/Integration/GlobalId/NodeDirectiveDBTest.php
+++ b/tests/Integration/GlobalId/NodeDirectiveDBTest.php
@@ -33,31 +33,31 @@ protected function setUp(): void
 
     public function testResolveNodes(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type User @node(resolver: "Tests\\\Integration\\\GlobalId\\\NodeDirectiveDBTest@resolveNode") {
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+        type User @node(resolver: "Tests\\Integration\\GlobalId\\NodeDirectiveDBTest@resolveNode") {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $firstGlobalId = $this->globalIdResolver->encode('User', self::TEST_TUPLES[1]['id']);
         $secondGlobalId = $this->globalIdResolver->encode('User', self::TEST_TUPLES[2]['id']);
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            first: node(id: \"{$firstGlobalId}\") {
+            first: node(id: "{$firstGlobalId}") {
                 id
                 ...on User {
                     name
                 }
             }
-            second: node(id: \"{$secondGlobalId}\") {
+            second: node(id: "{$secondGlobalId}") {
                 id
                 ...on User {
                     name
                 }
             }
         }
-        ")->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'first' => [
                     'id' => $firstGlobalId,
@@ -73,27 +73,27 @@ public function testResolveNodes(): void
 
     public function testResolveNodesViaInterface(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         interface IUser {
             name: String!
         }
-        type User implements IUser @node(resolver: "Tests\\\Integration\\\GlobalId\\\NodeDirectiveDBTest@resolveNode") {
+        type User implements IUser @node(resolver: "Tests\\Integration\\GlobalId\\NodeDirectiveDBTest@resolveNode") {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $globalId = $this->globalIdResolver->encode('User', self::TEST_TUPLES[1]['id']);
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            node: node(id: \"{$globalId}\") {
+            node: node(id: "{$globalId}") {
                 id
                 ...on IUser {
                     name
                 }
             }
         }
-        ")->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'node' => [
                     'id' => $globalId,
@@ -105,20 +105,20 @@ interface IUser {
 
     public function testUnknownNodeType(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type User @node(resolver: "Tests\\\Integration\\\GlobalId\\\NodeDirectiveDBTest@resolveNode") {
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+        type User @node(resolver: "Tests\\Integration\\GlobalId\\NodeDirectiveDBTest@resolveNode") {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $globalId = $this->globalIdResolver->encode('WrongClass', self::TEST_TUPLES[1]['id']);
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            node: node(id: \"{$globalId}\") {
+            node: node(id: "{$globalId}") {
                 id
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'node' => null,
             ],
@@ -132,24 +132,24 @@ public function testUnknownNodeType(): void
 
     public function testTypeWithoutNodeDirective(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type User @node(resolver: "Tests\\\Integration\\\Schema\\\NodeDirectiveDBTest@resolveNode") {
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+        type User @node(resolver: "Tests\\Integration\\Schema\\NodeDirectiveDBTest@resolveNode") {
             name: String!
         }
 
         type User2 {
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $globalId = $this->globalIdResolver->encode('User2', self::TEST_TUPLES[1]['id']);
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            node: node(id: \"{$globalId}\") {
+            node: node(id: "{$globalId}") {
                 id
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'node' => null,
             ],
@@ -171,11 +171,11 @@ public static function resolveNode(int|string $id): array
     #[DataProvider('modelNodeDirectiveStyles')]
     public function testResolveModelsNodes(string $directiveDefinition): void
     {
-        $this->schema .= /** @lang GraphQL */ "
+        $this->schema .= /** @lang GraphQL */ <<<GRAPHQL
         type User {$directiveDefinition} {
             name: String!
         }
-        ";
+        GRAPHQL;
 
         $user = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user);
@@ -184,16 +184,16 @@ public function testResolveModelsNodes(string $directiveDefinition): void
 
         $globalId = $this->globalIdResolver->encode('User', $user->getKey());
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            node(id: \"{$globalId}\") {
+            node(id: "{$globalId}") {
                 id
                 ...on User {
                     name
                 }
             }
         }
-        ")->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'node' => [
                     'id' => $globalId,
@@ -213,11 +213,11 @@ public static function modelNodeDirectiveStyles(): iterable
     public function testThrowsWhenNodeDirectiveIsDefinedOnNonObjectType(): void
     {
         $this->expectException(DefinitionException::class);
-        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         input Foo @node {
             bar: ID
         }
-        ');
+        GRAPHQL);
     }
 
     public function testPreservesCustomNodeField(): void
@@ -225,7 +225,7 @@ public function testPreservesCustomNodeField(): void
         $result = 42;
         $this->mockResolver($result);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             # Nonsensical example, just done this way for ease of testing.
             # Usually customization would have the purpose of adding middleware.
@@ -235,13 +235,13 @@ public function testPreservesCustomNodeField(): void
         type User @node {
             name: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             node
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'node' => $result,
             ],
diff --git a/tests/Integration/GraphQLTest.php b/tests/Integration/GraphQLTest.php
index b24ae5bbff..5a3a11ca50 100644
--- a/tests/Integration/GraphQLTest.php
+++ b/tests/Integration/GraphQLTest.php
@@ -8,21 +8,21 @@
 
 final class GraphQLTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         foo: Int
         bar: String
     }
-    ';
+    GRAPHQL;
 
     public function testResolvesQueryViaPostRequest(): void
     {
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree()
             ->assertExactJson([
                 'data' => [
@@ -38,11 +38,11 @@ public function testResolvesQueryViaGetRequest(): void
                 'graphql?'
                 . http_build_query(
                     [
-                        'query' => /** @lang GraphQL */ '
+                        'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                         {
                             foo
                         }
-                        ',
+                        GRAPHQL,
                     ],
                 ),
             )
@@ -57,14 +57,14 @@ public function testResolvesNamedOperation(): void
     {
         $this
             ->postGraphQL([
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                     query Foo {
                         foo
                     }
                     query Bar {
                         bar
                     }
-                ',
+                GRAPHQL,
                 'operationName' => 'Bar',
             ])
             ->assertExactJson([
@@ -79,18 +79,18 @@ public function testResolveBatchedQueries(): void
         $this
             ->postGraphQL([
                 [
-                    'query' => /** @lang GraphQL */ '
+                    'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                         {
                             foo
                         }
-                        ',
+                    GRAPHQL,
                 ],
                 [
-                    'query' => /** @lang GraphQL */ '
+                    'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                         {
                             bar
                         }
-                        ',
+                    GRAPHQL,
                 ],
             ])
             ->assertExactJson([
diff --git a/tests/Integration/IntrospectionTest.php b/tests/Integration/IntrospectionTest.php
index 8ef219db4f..4af8df8556 100644
--- a/tests/Integration/IntrospectionTest.php
+++ b/tests/Integration/IntrospectionTest.php
@@ -21,11 +21,11 @@ protected function setUp(): void
 
     public function testFindsTypesFromSchema(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar: Int
         }
-        ';
+        GRAPHQL;
 
         $this->assertNotNull(
             $this->introspectType('Foo'),
diff --git a/tests/Integration/LifecycleEventsTest.php b/tests/Integration/LifecycleEventsTest.php
index 2eb14e2c8f..661fb763c5 100644
--- a/tests/Integration/LifecycleEventsTest.php
+++ b/tests/Integration/LifecycleEventsTest.php
@@ -35,17 +35,17 @@ public function testDispatchesProperLifecycleEvents(): void
 
         $this->mockResolver();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
            foo: Int @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
 
         [
             $startRequest,
diff --git a/tests/Integration/Models/PropertyAccessTest.php b/tests/Integration/Models/PropertyAccessTest.php
index a95583e589..29372d2731 100644
--- a/tests/Integration/Models/PropertyAccessTest.php
+++ b/tests/Integration/Models/PropertyAccessTest.php
@@ -16,7 +16,7 @@ public function testLaravelDatabaseProperty(): void
         $user->name = $name;
         $user->save();
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -27,13 +27,13 @@ public function testLaravelDatabaseProperty(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 name
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -49,7 +49,7 @@ public function testLaravelFunctionProperty(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             laravel_function_property: String!
@@ -60,13 +60,13 @@ public function testLaravelFunctionProperty(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 laravel_function_property
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -83,7 +83,7 @@ public function testPhpProperty(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             php_property: String
@@ -94,13 +94,13 @@ public function testPhpProperty(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 php_property
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -118,7 +118,7 @@ public function testPrefersAttributeAccessorThatShadowsPhpProperty(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             incrementing: String!
@@ -129,13 +129,13 @@ public function testPrefersAttributeAccessorThatShadowsPhpProperty(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 incrementing
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -152,7 +152,7 @@ public function testPrefersAttributeAccessorNullThatShadowsPhpProperty(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             exists: Boolean
@@ -163,13 +163,13 @@ public function testPrefersAttributeAccessorNullThatShadowsPhpProperty(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 exists
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -186,7 +186,7 @@ public function testExpensivePropertyIsOnlyCalledOnce(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             expensive_property: Int!
@@ -197,13 +197,13 @@ public function testExpensivePropertyIsOnlyCalledOnce(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 expensive_property
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/MultipleRequestsTest.php b/tests/Integration/MultipleRequestsTest.php
index 1e4d2f1221..ada96a21bb 100644
--- a/tests/Integration/MultipleRequestsTest.php
+++ b/tests/Integration/MultipleRequestsTest.php
@@ -10,27 +10,27 @@ public function testFireMultipleRequestsInOneTest(): void
     {
         $this->mockResolver(static fn ($_, array $args): string => $args['this']);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             return(this: String!): String @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             return(this: "foo")
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'return' => 'foo',
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             return(this: "bar")
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'return' => 'bar',
             ],
diff --git a/tests/Integration/OrderBy/OrderByDirectiveDBTest.php b/tests/Integration/OrderBy/OrderByDirectiveDBTest.php
index 2d4b4c8166..ba085175e6 100644
--- a/tests/Integration/OrderBy/OrderByDirectiveDBTest.php
+++ b/tests/Integration/OrderBy/OrderByDirectiveDBTest.php
@@ -9,7 +9,7 @@
 
 final class OrderByDirectiveDBTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         users(
             orderBy: _ @orderBy
@@ -26,14 +26,14 @@ final class OrderByDirectiveDBTest extends DBTestCase
     enum UserColumn {
         NAME @enum(value: "name")
     }
-    ';
+    GRAPHQL;
 
     public function testOrderByTheGivenColumnAndSortOrderASC(): void
     {
         $this->createUser('B');
         $this->createUser('A');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -46,7 +46,7 @@ public function testOrderByTheGivenColumnAndSortOrderASC(): void
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -65,7 +65,7 @@ public function testOrderByTheGivenFieldAndSortOrderDESC(): void
         $this->createUser('B');
         $this->createUser('A');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -78,7 +78,7 @@ public function testOrderByTheGivenFieldAndSortOrderDESC(): void
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -98,7 +98,7 @@ public function testOrderByMultipleColumns(): void
         $this->createUser('A', 5);
         $this->createUser('C', 2);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -116,7 +116,7 @@ public function testOrderByMultipleColumns(): void
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -141,7 +141,7 @@ public function testOrderWithRestrictedColumns(): void
         $this->createUser('B');
         $this->createUser('A');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderByRestricted: [
@@ -154,7 +154,7 @@ public function testOrderWithRestrictedColumns(): void
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -173,7 +173,7 @@ public function testUseColumnEnumsArg(): void
         $this->createUser('B');
         $this->createUser('A');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderByRestrictedEnum: [
@@ -186,7 +186,7 @@ public function testUseColumnEnumsArg(): void
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -204,7 +204,7 @@ public function testRejectsDefinitionWithDuplicateColumnArgument(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 orderBy: _ @orderBy(columns: ["name"], columnsEnum: "UserColumn")
@@ -219,7 +219,7 @@ public function testRejectsDefinitionWithDuplicateColumnArgument(): void
         enum UserColumn {
             NAME @enum(value: "name")
         }
-        ');
+        GRAPHQL);
     }
 
     public function testOrderColumnOnField(): void
@@ -234,7 +234,7 @@ public function testOrderColumnOnField(): void
         $userB->name = 'B';
         $userB->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             latestUsers: [User!]!
                 @all
@@ -244,15 +244,15 @@ public function testOrderColumnOnField(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             latestUsers {
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'latestUsers' => [
                     [
@@ -268,7 +268,7 @@ public function testOrderColumnOnField(): void
 
     public function testOrderByRelationCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 orderBy: _ @orderBy(relations: [
@@ -282,7 +282,7 @@ public function testOrderByRelationCount(): void
         type User {
             id: Int!
         }
-        ';
+        GRAPHQL;
 
         $userA = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userA);
@@ -297,7 +297,7 @@ public function testOrderByRelationCount(): void
             factory(Task::class, 2)->create(),
         );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -310,7 +310,7 @@ public function testOrderByRelationCount(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -323,7 +323,7 @@ public function testOrderByRelationCount(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -336,7 +336,7 @@ public function testOrderByRelationCount(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -352,7 +352,7 @@ public function testOrderByRelationCount(): void
 
     public function testOrderByRelationAggregate(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(
                 orderBy: _ @orderBy(relations: [
@@ -371,7 +371,7 @@ public function testOrderByRelationAggregate(): void
         enum UserColumn {
             NAME @enum(value: "name")
         }
-        ';
+        GRAPHQL;
 
         $userA = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userA);
@@ -389,7 +389,7 @@ enum UserColumn {
         $taskB1->difficulty = 2;
         $userB->tasks()->save($taskB1);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -402,7 +402,7 @@ enum UserColumn {
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -415,7 +415,7 @@ enum UserColumn {
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 orderBy: [
@@ -428,7 +428,7 @@ enum UserColumn {
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
diff --git a/tests/Integration/OrderBy/OrderByDirectiveTest.php b/tests/Integration/OrderBy/OrderByDirectiveTest.php
index 1da4e882e8..68406cf9e0 100644
--- a/tests/Integration/OrderBy/OrderByDirectiveTest.php
+++ b/tests/Integration/OrderBy/OrderByDirectiveTest.php
@@ -10,13 +10,13 @@ final class OrderByDirectiveTest extends TestCase
 {
     public function testGeneratesInputWithFullyQualifiedName(): void
     {
-        $schemaString = /** @lang GraphQL */ '
+        $schemaString = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 orderBy: _ @orderBy(columns: ["bar"])
             ): ID @mock
         }
-        ';
+        GRAPHQL;
 
         $schema = $this->buildSchema($schemaString);
         $input = $schema->getType(
@@ -30,7 +30,7 @@ public function testGeneratesInputWithFullyQualifiedName(): void
 
     public function testGeneratesInputWithFullyQualifiedNameUsingRelations(): void
     {
-        $schemaString = /** @lang GraphQL */ '
+        $schemaString = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 orderBy: _ @orderBy(
@@ -42,7 +42,7 @@ public function testGeneratesInputWithFullyQualifiedNameUsingRelations(): void
                 )
             ): ID @mock
         }
-        ';
+        GRAPHQL;
 
         $schema = $this->buildSchema($schemaString);
 
@@ -82,7 +82,7 @@ public function testGeneratesInputWithFullyQualifiedNameUsingRelations(): void
 
     public function testValidatesOnlyColumnOrOneRelationIsUsed(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 orderBy: _ @orderBy(
@@ -94,10 +94,10 @@ public function testValidatesOnlyColumnOrOneRelationIsUsed(): void
                 )
             ): ID @mock
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(orderBy: [{
                     column: BAR
@@ -105,12 +105,12 @@ public function testValidatesOnlyColumnOrOneRelationIsUsed(): void
                     order: ASC
                 }])
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('orderBy.0.column', 'The order by.0.column field prohibits order by.0.foo / order by.0.baz from being present.')
             ->assertGraphQLValidationError('orderBy.0.foo', 'The order by.0.foo field prohibits order by.0.column / order by.0.baz from being present.');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(orderBy: [{
                     foo: { aggregate: COUNT }
@@ -118,7 +118,7 @@ public function testValidatesOnlyColumnOrOneRelationIsUsed(): void
                     order: ASC
                 }])
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('orderBy.0.foo', 'The order by.0.foo field prohibits order by.0.column / order by.0.baz from being present.')
             ->assertGraphQLValidationError('orderBy.0.baz', 'The order by.0.baz field prohibits order by.0.column / order by.0.foo from being present.');
     }
diff --git a/tests/Integration/Pagination/PaginateDirectiveDBTest.php b/tests/Integration/Pagination/PaginateDirectiveDBTest.php
index 3a88b068a9..b49ac5e718 100644
--- a/tests/Integration/Pagination/PaginateDirectiveDBTest.php
+++ b/tests/Integration/Pagination/PaginateDirectiveDBTest.php
@@ -23,7 +23,7 @@ public function testPaginate(): void
     {
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -31,9 +31,9 @@ public function testPaginate(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 paginatorInfo {
@@ -46,7 +46,7 @@ public function testPaginate(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -75,7 +75,7 @@ public function testSpecifyCustomBuilder(): void
 GRAPHQL;
 
         // The custom builder is supposed to change the sort order
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 1) {
                 data {
@@ -83,7 +83,7 @@ public function testSpecifyCustomBuilder(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'data' => [
@@ -120,7 +120,7 @@ public function testSpecifyCustomBuilderForRelation(): void
 GRAPHQL;
 
         // The custom builder is supposed to change the sort order
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             user(id: {$user->id}) {
                 posts(first: 10) {
@@ -130,7 +130,7 @@ public function testSpecifyCustomBuilderForRelation(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'posts' => [
@@ -185,7 +185,7 @@ public function testSpecifyCustomBuilderForScoutBuilder(): void
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($first: Int!, $page: Int!, $id: ID!) {
             posts(first: $first, page: $page, id: $id) {
                 data {
@@ -193,7 +193,7 @@ public function testSpecifyCustomBuilderForScoutBuilder(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'first' => $first,
             'page' => $page,
             'id' => $post->id,
@@ -222,7 +222,7 @@ public function testPaginateWithScopes(): void
         $unnamedUser->name = null;
         $unnamedUser->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: String!
         }
@@ -230,9 +230,9 @@ public function testPaginateWithScopes(): void
         type Query {
             users: [User!]! @paginate(scopes: ["named"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 5) {
                 paginatorInfo {
@@ -245,7 +245,7 @@ public function testPaginateWithScopes(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -306,7 +306,7 @@ public function testCreateQueryPaginatorsWithDifferentPages(): void
             $comment->save();
         }
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             posts: [Post!]! @paginate
         }
@@ -322,9 +322,9 @@ public function testCreateQueryPaginatorsWithDifferentPages(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2, page: 1) {
                 paginatorInfo {
@@ -352,7 +352,7 @@ public function testCreateQueryPaginatorsWithDifferentPages(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -385,7 +385,7 @@ public function testCreateQueryConnections(): void
     {
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -393,9 +393,9 @@ public function testCreateQueryConnections(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 pageInfo {
@@ -408,7 +408,7 @@ public function testCreateQueryConnections(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'pageInfo' => [
@@ -421,7 +421,7 @@ public function testCreateQueryConnections(): void
 
     public function testQueriesConnectionWithNoData(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -429,9 +429,9 @@ public function testQueriesConnectionWithNoData(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 5) {
                 pageInfo {
@@ -451,7 +451,7 @@ public function testQueriesConnectionWithNoData(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     'pageInfo' => [
@@ -472,7 +472,7 @@ public function testQueriesConnectionWithNoData(): void
 
     public function testQueriesPaginationWithNoData(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -480,9 +480,9 @@ public function testQueriesPaginationWithNoData(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 5) {
                 paginatorInfo {
@@ -500,7 +500,7 @@ public function testQueriesPaginationWithNoData(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -524,7 +524,7 @@ public function testQueriesFirst0(): void
         $amount = 3;
         factory(User::class, $amount)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -532,9 +532,9 @@ public function testQueriesFirst0(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 0) {
                 paginatorInfo {
@@ -552,7 +552,7 @@ public function testQueriesFirst0(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -576,7 +576,7 @@ public function testQueriesPaginationWithoutPaginatorInfo(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -584,10 +584,10 @@ public function testQueriesPaginationWithoutPaginatorInfo(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($user): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(first: 1) {
                     data {
@@ -595,7 +595,7 @@ public function testQueriesPaginationWithoutPaginatorInfo(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'users' => [
                         'data' => [
@@ -614,7 +614,7 @@ public function testQueriesConnectionWithoutPageInfo(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -622,10 +622,10 @@ public function testQueriesConnectionWithoutPageInfo(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($user): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(first: 1) {
                     edges {
@@ -635,7 +635,7 @@ public function testQueriesConnectionWithoutPageInfo(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'users' => [
                         'edges' => [
@@ -655,7 +655,7 @@ public function testQueriesConnectionPageOffset(): void
     {
         $users = factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -663,10 +663,10 @@ public function testQueriesConnectionPageOffset(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($users): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($after: String!) {
                 users(first: 2, after: $after) {
                     pageInfo {
@@ -686,7 +686,7 @@ public function testQueriesConnectionPageOffset(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'after' => Cursor::encode(2),
             ])->assertJson([
                 'data' => [
@@ -718,7 +718,7 @@ public function testQueriesConnectionPageOffsetWithoutPageInfo(): void
     {
         $users = factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -726,12 +726,12 @@ public function testQueriesConnectionPageOffsetWithoutPageInfo(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ';
+        GRAPHQL;
 
         $cursor = Cursor::encode(2);
 
         $this->assertQueryCountMatches(1, function () use ($users): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($after: String!) {
                 users(first: 2, after: $after) {
                     edges {
@@ -741,7 +741,7 @@ public function testQueriesConnectionPageOffsetWithoutPageInfo(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'after' => Cursor::encode(2),
             ])->assertJson([
                 'data' => [
@@ -763,7 +763,7 @@ public function testPaginatesWhenDefinedInTypeExtension(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -771,9 +771,9 @@ public function testPaginatesWhenDefinedInTypeExtension(): void
         extend type Query {
             users: [User!]! @paginate(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 1) {
                 data {
@@ -781,14 +781,14 @@ public function testPaginatesWhenDefinedInTypeExtension(): void
                 }
             }
         }
-        ')->assertJsonCount(1, 'data.users.data');
+        GRAPHQL)->assertJsonCount(1, 'data.users.data');
     }
 
     public function testDefaultPaginationCount(): void
     {
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -796,9 +796,9 @@ public function testDefaultPaginationCount(): void
         type Query {
             users: [User!]! @paginate(defaultCount: 2)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 paginatorInfo {
@@ -811,7 +811,7 @@ public function testDefaultPaginationCount(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -829,7 +829,7 @@ public function testDoesNotRequireDefaultCountArgIfDefinedInConfig(): void
         $defaultCount = 2;
         config(['lighthouse.pagination.default_count' => $defaultCount]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -838,9 +838,9 @@ public function testDoesNotRequireDefaultCountArgIfDefinedInConfig(): void
         type Query {
             users: [User!] @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 data {
@@ -848,14 +848,14 @@ public function testDoesNotRequireDefaultCountArgIfDefinedInConfig(): void
                 }
             }
         }
-        ')->assertJsonCount($defaultCount, 'data.users.data');
+        GRAPHQL)->assertJsonCount($defaultCount, 'data.users.data');
     }
 
     public function testIsUnlimitedByMaxCountFromDirective(): void
     {
         config(['lighthouse.pagination.max_count' => 5]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -864,10 +864,10 @@ public function testIsUnlimitedByMaxCountFromDirective(): void
         type Query {
             users: [User!]! @paginate(maxCount: null)
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(first: 10) {
                     data {
@@ -876,7 +876,7 @@ public function testIsUnlimitedByMaxCountFromDirective(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree();
     }
 
@@ -885,7 +885,7 @@ public function testQueriesSimplePagination(): void
         config(['lighthouse.pagination.default_count' => 10]);
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -895,11 +895,11 @@ public function testQueriesSimplePagination(): void
             usersPaginated: [User!] @paginate(type: PAGINATOR)
             usersSimplePaginated: [User!] @paginate(type: SIMPLE)
         }
-        ';
+        GRAPHQL;
 
         // "paginate" fires 2 queries: One for data, one for counting.
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 usersPaginated {
                     paginatorInfo {
@@ -910,12 +910,12 @@ public function testQueriesSimplePagination(): void
                     }
                 }
             }
-            ')->assertJsonCount(3, 'data.usersPaginated.data');
+            GRAPHQL)->assertJsonCount(3, 'data.usersPaginated.data');
         });
 
         // "simplePaginate" only fires one query for the data.
         $this->assertQueryCountMatches(1, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 usersSimplePaginated {
                     data {
@@ -923,7 +923,7 @@ public function testQueriesSimplePagination(): void
                     }
                 }
             }
-            ')->assertJsonCount(3, 'data.usersSimplePaginated.data');
+            GRAPHQL)->assertJsonCount(3, 'data.usersSimplePaginated.data');
         });
     }
 
@@ -932,7 +932,7 @@ public function testGetSimplePaginationAttributes(): void
         config(['lighthouse.pagination.default_count' => 10]);
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -941,9 +941,9 @@ public function testGetSimplePaginationAttributes(): void
         type Query {
             users: [User!] @paginate(type: SIMPLE)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 paginatorInfo {
@@ -955,7 +955,7 @@ public function testGetSimplePaginationAttributes(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -975,7 +975,7 @@ public function testPaginateWithCacheDirective(): void
         $this->expectNotToPerformAssertions();
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -983,9 +983,9 @@ public function testPaginateWithCacheDirective(): void
         type Query {
             users: [User!]! @paginate @cache
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 data {
@@ -993,9 +993,9 @@ public function testPaginateWithCacheDirective(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 2) {
                 paginatorInfo {
@@ -1008,14 +1008,14 @@ public function testPaginateWithCacheDirective(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testSimplePaginationWithNullPageUsesDefaultPage(): void
     {
         factory(User::class, 3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -1024,9 +1024,9 @@ public function testSimplePaginationWithNullPageUsesDefaultPage(): void
         type Query {
             users: [User!] @paginate(type: SIMPLE)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($page: Int) {
             users(first: 2, page: $page) {
                 paginatorInfo {
@@ -1038,7 +1038,7 @@ public function testSimplePaginationWithNullPageUsesDefaultPage(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'page' => null,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Pennant/FeatureDirectiveTest.php b/tests/Integration/Pennant/FeatureDirectiveTest.php
index 3cce571f79..b4b89850fb 100644
--- a/tests/Integration/Pennant/FeatureDirectiveTest.php
+++ b/tests/Integration/Pennant/FeatureDirectiveTest.php
@@ -42,7 +42,7 @@ protected function getPackageProviders($app): array
 
     public function testUnavailableWhenFeatureIsInactive(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenActive: String!
                 @feature(name: "new-api", when: ACTIVE)
@@ -50,7 +50,7 @@ public function testUnavailableWhenFeatureIsInactive(): void
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenActive
         }
@@ -61,7 +61,7 @@ public function testUnavailableWhenFeatureIsInactive(): void
 
     public function testUnavailableWhenFeatureIsInactiveWithDefaultFeatureState(): void
     {
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenActive: String!
                 @feature(name: "new-api")
@@ -69,7 +69,7 @@ public function testUnavailableWhenFeatureIsInactiveWithDefaultFeatureState(): v
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenActive
         }
@@ -81,7 +81,7 @@ public function testUnavailableWhenFeatureIsInactiveWithDefaultFeatureState(): v
     public function testUnavailableWhenFeatureIsActive(): void
     {
         Feature::define('new-api', static fn (): bool => true);
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenInactive: String!
                 @feature(name: "new-api", when: INACTIVE)
@@ -89,7 +89,7 @@ public function testUnavailableWhenFeatureIsActive(): void
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenInactive
         }
@@ -103,7 +103,7 @@ public function testAvailableWhenFeatureIsActive(): void
         Feature::define('new-api', static fn (): bool => true);
         $fieldValue = 'active';
         $this->mockResolver(static fn (): string => $fieldValue);
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenActive: String!
                 @feature(name: "new-api", when: ACTIVE)
@@ -111,7 +111,7 @@ public function testAvailableWhenFeatureIsActive(): void
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenActive
         }
@@ -130,7 +130,7 @@ public function testAvailableWhenFeatureIsActiveWithDefaultFeatureState(): void
         Feature::define('new-api', static fn (): bool => true);
         $fieldValue = 'active';
         $this->mockResolver(static fn (): string => $fieldValue);
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenActive: String!
                 @feature(name: "new-api")
@@ -138,7 +138,7 @@ public function testAvailableWhenFeatureIsActiveWithDefaultFeatureState(): void
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenActive
         }
@@ -156,7 +156,7 @@ public function testAvailableWhenFeatureIsInactive(): void
     {
         $fieldValue = 'inactive';
         $this->mockResolver(static fn (): string => $fieldValue);
-        $this->schema = /* @lang GraphQL */ <<<'GRAPHQL'
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             fieldWhenInactive: String!
                 @feature(name: "new-api", when: INACTIVE)
@@ -164,7 +164,7 @@ public function testAvailableWhenFeatureIsInactive(): void
         }
         GRAPHQL;
 
-        $response = $this->graphQL(/* @lang GraphQL */ <<<'GRAPHQL'
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             fieldWhenInactive
         }
diff --git a/tests/Integration/QueryCacheTest.php b/tests/Integration/QueryCacheTest.php
index 23c659febd..8f17003c79 100644
--- a/tests/Integration/QueryCacheTest.php
+++ b/tests/Integration/QueryCacheTest.php
@@ -72,12 +72,12 @@ public function testDifferentQueriesHasDifferentKeys(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
diff --git a/tests/Integration/ReportingErrorHandlerTest.php b/tests/Integration/ReportingErrorHandlerTest.php
index e7b77620f9..1b1cc0ec81 100644
--- a/tests/Integration/ReportingErrorHandlerTest.php
+++ b/tests/Integration/ReportingErrorHandlerTest.php
@@ -9,11 +9,11 @@
 
 final class ReportingErrorHandlerTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         foo: ID @mock
     }
-    ';
+    GRAPHQL;
 
     public function testReportsNonClientSafeErrors(): void
     {
@@ -27,11 +27,11 @@ public function testReportsNonClientSafeErrors(): void
             ->with($exception);
         $this->app->singleton(ExceptionHandler::class, static fn (): MockObject => $handler);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testDoesNotReportClientSafeErrors(): void
@@ -46,10 +46,10 @@ public function testDoesNotReportClientSafeErrors(): void
             ->with($error);
         $this->app->singleton(ExceptionHandler::class, static fn (): MockObject => $handler);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/AggregateDirectiveTest.php b/tests/Integration/Schema/Directives/AggregateDirectiveTest.php
index 6abb29be43..e43a51c796 100644
--- a/tests/Integration/Schema/Directives/AggregateDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/AggregateDirectiveTest.php
@@ -13,41 +13,41 @@ final class AggregateDirectiveTest extends DBTestCase
 {
     public function testRequiresARelationOrModelArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks: Int @aggregate
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks
         }
-        ');
+        GRAPHQL);
     }
 
     public function testAggregateModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             sum: Int! @aggregate(model: "Task", function: SUM, column: "difficulty")
             avg: Float! @aggregate(model: "Task", function: AVG, column: "difficulty")
             min: Int! @aggregate(model: "Task", function: MIN, column: "difficulty")
             max: Int! @aggregate(model: "Task", function: MAX, column: "difficulty")
         }
-        ';
+        GRAPHQL;
 
         $tasks = factory(Task::class, 3)->create();
 
-        $response = $this->graphQL(/** @lang GraphQL */ '
+        $response = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             sum
             avg
             min
             max
         }
-        ');
+        GRAPHQL);
 
         $response->assertJson([
             'data' => [
@@ -66,11 +66,11 @@ public function testAggregateModel(): void
 
     public function testSumModelWithScopes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             finished: Int! @aggregate(model: "Task", function: SUM, column: "difficulty", scopes: ["completed"])
         }
-        ';
+        GRAPHQL;
 
         factory(Task::class, 3)->create();
         $completed = factory(Task::class, 2)->create();
@@ -79,11 +79,11 @@ public function testSumModelWithScopes(): void
             $task->save();
         });
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             finished
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'finished' => $completed->sum('difficulty'),
             ],
@@ -92,7 +92,7 @@ public function testSumModelWithScopes(): void
 
     public function testSumRelationEagerLoad(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!] @all
         }
@@ -100,7 +100,7 @@ public function testSumRelationEagerLoad(): void
         type User {
             workload: Int! @aggregate(relation: "tasks", function: SUM, column: "difficulty")
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 3)
             ->create()
@@ -113,13 +113,13 @@ public function testSumRelationEagerLoad(): void
             });
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     workload
                 }
             }
-            ')->assertExactJson([
+            GRAPHQL)->assertExactJson([
                 'data' => [
                     'users' => [
                         [
@@ -139,7 +139,7 @@ public function testSumRelationEagerLoad(): void
 
     public function testSumRelationWithScopes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -147,7 +147,7 @@ public function testSumRelationWithScopes(): void
         type User {
             finished: Int! @aggregate(relation: "tasks", function: SUM, column: "difficulty", scopes: ["completed"])
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -159,13 +159,13 @@ public function testSumRelationWithScopes(): void
         $this->assertInstanceOf(Task::class, $completed);
         $user->tasks()->save($completed);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 finished
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => [
                     'finished' => $completed->difficulty,
@@ -176,7 +176,7 @@ public function testSumRelationWithScopes(): void
 
     public function testMultipleAggregatesOnSameRelationWithAliases(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             difficulty(
                 minimum: Int @where(key: "difficulty", operator: ">=")
@@ -187,7 +187,7 @@ public function testMultipleAggregatesOnSameRelationWithAliases(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user1 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user1);
@@ -216,14 +216,14 @@ public function testMultipleAggregatesOnSameRelationWithAliases(): void
         $user2->tasks()->save($high2);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query {
                 users {
                     lowDifficulty: difficulty(maximum: 9000)
                     highDifficulty: difficulty(minimum: 9000)
                 }
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'users' => [
@@ -242,14 +242,14 @@ public function testMultipleAggregatesOnSameRelationWithAliases(): void
 
     public function testAggregateWithBuilder(): void
     {
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Query {
             sum(
                 difficulty: Int! @eq
                 exclude: ID!
-            ): Int! @aggregate(builder: \"{$this->qualifyTestResolver('builder')}\", function: SUM, column: \"difficulty\")
+            ): Int! @aggregate(builder: "{$this->qualifyTestResolver('builder')}", function: SUM, column: "difficulty")
         }
-        ";
+        GRAPHQL;
 
         $difficulty = 5;
 
@@ -273,11 +273,11 @@ public function testAggregateWithBuilder(): void
         $task4->difficulty = $difficulty;
         $task4->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($difficulty: Int!, $exclude: ID!) {
             sum(difficulty: $difficulty, exclude: $exclude)
         }
-        ', [
+        GRAPHQL, [
             'difficulty' => $difficulty,
             'exclude' => $task4->id,
         ])->assertJson([
diff --git a/tests/Integration/Schema/Directives/AllDirectiveTest.php b/tests/Integration/Schema/Directives/AllDirectiveTest.php
index f206c82250..2be3c1d2cd 100644
--- a/tests/Integration/Schema/Directives/AllDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/AllDirectiveTest.php
@@ -22,7 +22,7 @@ public function testGetAllModelsAsRootField(): void
         $count = 2;
         factory(User::class, $count)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -30,15 +30,15 @@ public function testGetAllModelsAsRootField(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
             }
         }
-        ')->assertJsonCount($count, 'data.users');
+        GRAPHQL)->assertJsonCount($count, 'data.users');
     }
 
     public function testExplicitModelName(): void
@@ -46,7 +46,7 @@ public function testExplicitModelName(): void
         $count = 2;
         factory(User::class, $count)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             id: ID!
         }
@@ -54,15 +54,15 @@ public function testExplicitModelName(): void
         type Query {
             foos: [Foo!]! @all(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foos {
                 id
             }
         }
-        ')->assertJsonCount($count, 'data.foos');
+        GRAPHQL)->assertJsonCount($count, 'data.foos');
     }
 
     public function testRenamedModelWithModelDirective(): void
@@ -70,7 +70,7 @@ public function testRenamedModelWithModelDirective(): void
         $count = 2;
         factory(User::class, $count)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @model(class: "User") {
             id: ID!
         }
@@ -78,15 +78,15 @@ public function testRenamedModelWithModelDirective(): void
         type Query {
             foos: [Foo!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foos {
                 id
             }
         }
-        ')->assertJsonCount($count, 'data.foos');
+        GRAPHQL)->assertJsonCount($count, 'data.foos');
     }
 
     public function testGetAllAsNestedField(): void
@@ -99,7 +99,7 @@ public function testGetAllAsNestedField(): void
                 $post->save();
             });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             posts: [Post!]! @all
         }
@@ -111,9 +111,9 @@ public function testGetAllAsNestedField(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 posts {
@@ -121,7 +121,7 @@ public function testGetAllAsNestedField(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     [
@@ -154,7 +154,7 @@ public function testGetAllModelsFiltered(): void
         $users = factory(User::class, 3)->create();
         $userName = $users->first()->name;
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -163,16 +163,16 @@ public function testGetAllModelsFiltered(): void
         type Query {
             users(name: String @neq): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
-            users(name: \"{$userName}\") {
+            users(name: "{$userName}") {
                 id
                 name
             }
         }
-        ")->assertJsonCount(2, 'data.users');
+        GRAPHQL)->assertJsonCount(2, 'data.users');
     }
 
     public function testSpecifyCustomBuilder(): void
@@ -191,13 +191,13 @@ public function testSpecifyCustomBuilder(): void
         GRAPHQL;
 
         // The custom builder is supposed to change the sort order
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     [
@@ -235,7 +235,7 @@ public function testSpecifyCustomBuilderForRelation(): void
         GRAPHQL;
 
         // The custom builder is supposed to change the sort order
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             user(id: {$user->id}) {
                 posts {
@@ -243,7 +243,7 @@ public function testSpecifyCustomBuilderForRelation(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'posts' => [
@@ -284,13 +284,13 @@ public function testSpecifyCustomBuilderForScoutBuilder(): void
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             posts(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $post->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Schema/Directives/BelongsToDirectiveTest.php b/tests/Integration/Schema/Directives/BelongsToDirectiveTest.php
index 482a656868..929d16b6c7 100644
--- a/tests/Integration/Schema/Directives/BelongsToDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/BelongsToDirectiveTest.php
@@ -22,7 +22,7 @@ public function testResolveBelongsToRelationship(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -34,9 +34,9 @@ public function testResolveBelongsToRelationship(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 company {
@@ -44,7 +44,7 @@ public function testResolveBelongsToRelationship(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'company' => [
@@ -66,7 +66,7 @@ public function testResolveBelongsToWithCustomName(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -78,9 +78,9 @@ public function testResolveBelongsToWithCustomName(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 account {
@@ -88,7 +88,7 @@ public function testResolveBelongsToWithCustomName(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'account' => [
@@ -112,7 +112,7 @@ public function testResolveBelongsToRelationshipWithTwoRelation(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -129,9 +129,9 @@ public function testResolveBelongsToRelationshipWithTwoRelation(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 company {
@@ -142,7 +142,7 @@ public function testResolveBelongsToRelationshipWithTwoRelation(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'company' => [
@@ -160,7 +160,7 @@ public function testResolveBelongsToRelationshipWhenMainModelHasCompositePrimary
     {
         $products = factory(Product::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Color {
             id: ID!
             name: String
@@ -177,9 +177,9 @@ public function testResolveBelongsToRelationshipWhenMainModelHasCompositePrimary
         type Query {
             products: [Product] @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             products(first: 2) {
                 data{
@@ -193,7 +193,7 @@ public function testResolveBelongsToRelationshipWhenMainModelHasCompositePrimary
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'products' => [
                     'data' => [
@@ -223,7 +223,7 @@ public function testBelongsToItself(): void
         $child->parent()->associate($parent);
         $child->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: Int!
             parent: Post @belongsTo
@@ -232,10 +232,10 @@ public function testBelongsToItself(): void
         type Query {
             posts: [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 posts {
                     id
@@ -244,7 +244,7 @@ public function testBelongsToItself(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'posts' => [
@@ -274,7 +274,7 @@ public function testDoesNotShortcutForeignKeySelectionByDefault(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID! @rename(attribute: "uuid")
         }
@@ -286,9 +286,9 @@ public function testDoesNotShortcutForeignKeySelectionByDefault(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 company {
@@ -296,7 +296,7 @@ public function testDoesNotShortcutForeignKeySelectionByDefault(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'company' => [
@@ -323,7 +323,7 @@ public function testShortcutsForeignKeySelectID(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
         }
@@ -335,10 +335,10 @@ public function testShortcutsForeignKeySelectID(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $this->assertNoQueriesExecuted(function () use ($company): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     company {
@@ -346,7 +346,7 @@ public function testShortcutsForeignKeySelectID(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'user' => [
                         'company' => [
@@ -374,7 +374,7 @@ public function testShortcutsForeignKeySelectTypename(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
         }
@@ -386,10 +386,10 @@ public function testShortcutsForeignKeySelectTypename(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $this->assertNoQueriesExecuted(function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     company {
@@ -397,7 +397,7 @@ public function testShortcutsForeignKeySelectTypename(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'user' => [
                         'company' => [
@@ -425,7 +425,7 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
         }
@@ -437,10 +437,10 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $this->assertNoQueriesExecuted(function () use ($company): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     company {
@@ -449,7 +449,7 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'user' => [
                         'company' => [
@@ -476,7 +476,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -489,10 +489,10 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($company): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     company {
@@ -501,7 +501,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
                     }
                 }
             }
-            ')->assertJson([
+            GRAPHQL)->assertJson([
                 'data' => [
                     'user' => [
                         'company' => [
@@ -528,7 +528,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasConditions(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
         }
@@ -540,10 +540,10 @@ public function testDoesNotShortcutForeignKeyIfQueryHasConditions(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($company): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($name: String) {
                 user {
                     company(name: $name) {
@@ -551,7 +551,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasConditions(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'name' => "{$company->name} no match",
             ])->assertJson([
                 'data' => [
diff --git a/tests/Integration/Schema/Directives/BelongsToManyDirectiveTest.php b/tests/Integration/Schema/Directives/BelongsToManyDirectiveTest.php
index 460b8b5be6..24f10c5ee9 100644
--- a/tests/Integration/Schema/Directives/BelongsToManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/BelongsToManyDirectiveTest.php
@@ -12,7 +12,7 @@ final class BelongsToManyDirectiveTest extends DBTestCase
 {
     public function testQueryBelongsToManyRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany
         }
@@ -24,7 +24,7 @@ public function testQueryBelongsToManyRelationship(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -34,7 +34,7 @@ public function testQueryBelongsToManyRelationship(): void
         $roles = factory(Role::class, $rolesCount)->create();
         $user->roles()->attach($roles);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles {
@@ -42,12 +42,12 @@ public function testQueryBelongsToManyRelationship(): void
                 }
             }
         }
-        ')->assertJsonCount($rolesCount, 'data.user.roles');
+        GRAPHQL)->assertJsonCount($rolesCount, 'data.user.roles');
     }
 
     public function testNameRelationExplicitly(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             foo: [Role!] @belongsToMany(relation: "roles")
         }
@@ -59,7 +59,7 @@ public function testNameRelationExplicitly(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -69,7 +69,7 @@ public function testNameRelationExplicitly(): void
         $roles = factory(Role::class, $rolesCount)->create();
         $user->roles()->attach($roles);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 foo {
@@ -77,12 +77,12 @@ public function testNameRelationExplicitly(): void
                 }
             }
         }
-        ')->assertJsonCount($rolesCount, 'data.user.foo');
+        GRAPHQL)->assertJsonCount($rolesCount, 'data.user.foo');
     }
 
     public function testQueryBelongsToManyPaginator(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             rolesPaginated: [Role!]! @belongsToMany(type: PAGINATOR, relation: "roles")
             rolesSimplePaginated: [Role!]! @belongsToMany(type: SIMPLE, relation: "roles")
@@ -95,7 +95,7 @@ public function testQueryBelongsToManyPaginator(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -106,7 +106,7 @@ public function testQueryBelongsToManyPaginator(): void
         $user->roles()->attach($roles);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     rolesPaginated(first: 2) {
@@ -129,7 +129,7 @@ public function testQueryBelongsToManyPaginator(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'user' => [
@@ -154,7 +154,7 @@ public function testQueryBelongsToManyPaginator(): void
 
     public function testQueryBelongsToManyRelayConnection(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany(type: CONNECTION)
         }
@@ -166,7 +166,7 @@ public function testQueryBelongsToManyRelayConnection(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -175,7 +175,7 @@ public function testQueryBelongsToManyRelayConnection(): void
         $roles = factory(Role::class, 3)->create();
         $user->roles()->attach($roles);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles(first: 2) {
@@ -190,7 +190,7 @@ public function testQueryBelongsToManyRelayConnection(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'roles' => [
@@ -205,7 +205,7 @@ public function testQueryBelongsToManyRelayConnection(): void
 
     public function testQueryBelongsToManyRelayConnectionWithCustomEdgeUsingDirective(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany(type: CONNECTION, edgeType: "CustomRoleEdge")
         }
@@ -223,7 +223,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeUsingDirectiv
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -233,7 +233,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeUsingDirectiv
         $meta = ['meta' => 'new'];
         $user->roles()->attach($roles, $meta);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles(first: 2) {
@@ -246,7 +246,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeUsingDirectiv
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'roles' => [
@@ -261,7 +261,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeUsingDirectiv
 
     public function testQueryBelongsToManyRelayConnectionWithCustomEdgeHavingPivotFieldUsingDirective(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany(type: CONNECTION, edgeType: "UserRoleEdge")
         }
@@ -283,7 +283,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeHavingPivotFi
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -293,7 +293,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeHavingPivotFi
         $meta = ['meta' => 'new'];
         $user->roles()->attach($roles, $meta);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles(first: 2) {
@@ -308,13 +308,13 @@ public function testQueryBelongsToManyRelayConnectionWithCustomEdgeHavingPivotFi
                 }
             }
         }
-        ')->assertJsonPath('data.user.roles.edges.*.pivot', array_fill(0, 2, $meta))
+        GRAPHQL)->assertJsonPath('data.user.roles.edges.*.pivot', array_fill(0, 2, $meta))
             ->assertJsonCount(2, 'data.user.roles.edges');
     }
 
     public function testQueryBelongsToManyPivot(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany
         }
@@ -331,7 +331,7 @@ public function testQueryBelongsToManyPivot(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -342,7 +342,7 @@ public function testQueryBelongsToManyPivot(): void
         $meta = ['meta' => 'new'];
         $user->roles()->attach($roles, $meta);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles {
@@ -353,7 +353,7 @@ public function testQueryBelongsToManyPivot(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'roles' => [
@@ -371,7 +371,7 @@ public function testThrowsExceptionForInvalidEdgeTypeFromDirective(): void
         $this->expectExceptionObject(new DefinitionException(
             'The `edgeType` argument of @belongsToMany on roles must reference an existing object type definition.',
         ));
-        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany(type: CONNECTION, edgeType: "CustomRoleEdge")
         }
@@ -379,12 +379,12 @@ public function testThrowsExceptionForInvalidEdgeTypeFromDirective(): void
         type Role {
             id: ID!
         }
-        ');
+        GRAPHQL);
     }
 
     public function testQueryBelongsToManyRelayConnectionWithCustomMagicEdge(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles: [Role!]! @belongsToMany(type: CONNECTION)
         }
@@ -402,7 +402,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomMagicEdge(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -412,7 +412,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomMagicEdge(): void
         $meta = ['meta' => 'new'];
         $user->roles()->attach($roles, $meta);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles(first: 2) {
@@ -425,7 +425,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomMagicEdge(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'roles' => [
@@ -440,7 +440,7 @@ public function testQueryBelongsToManyRelayConnectionWithCustomMagicEdge(): void
 
     public function testQueryPaginatedBelongsToManyWithDuplicates(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User]! @all
         }
@@ -453,7 +453,7 @@ public function testQueryPaginatedBelongsToManyWithDuplicates(): void
         type Role {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
         $roles = factory(Role::class, 2)->create();
 
@@ -467,7 +467,7 @@ public function testQueryPaginatedBelongsToManyWithDuplicates(): void
             ->map(static fn (Role $role): array => ['id' => (string) $role->id])
             ->all();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
@@ -478,7 +478,7 @@ public function testQueryPaginatedBelongsToManyWithDuplicates(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => $users
                     ->map(static fn (User $user): array => [
@@ -494,7 +494,7 @@ public function testQueryPaginatedBelongsToManyWithDuplicates(): void
 
     public function testQueryBelongsToManyNestedRelationships(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             roles: [Role!]! @belongsToMany(type: CONNECTION)
@@ -513,7 +513,7 @@ public function testQueryBelongsToManyNestedRelationships(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -522,7 +522,7 @@ public function testQueryBelongsToManyNestedRelationships(): void
         $roles = factory(Role::class, 3)->create();
         $user->roles()->attach($roles);
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 roles(first: 2) {
@@ -553,7 +553,7 @@ public function testQueryBelongsToManyNestedRelationships(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertTrue($result->json('data.user.roles.pageInfo.hasNextPage'));
 
@@ -568,7 +568,7 @@ public function testQueryBelongsToManyNestedRelationships(): void
     public function testThrowsErrorWithUnknownTypeArg(): void
     {
         $this->expectExceptionObject(new DefinitionException('Found invalid pagination type: foo'));
-        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             roles(first: Int! after: Int): [Role!]! @belongsToMany(type: "foo")
         }
@@ -576,6 +576,6 @@ public function testThrowsErrorWithUnknownTypeArg(): void
         type Role {
             id: ID!
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/BuilderDirectiveTest.php b/tests/Integration/Schema/Directives/BuilderDirectiveTest.php
index 70b0bd89ca..7369084ec4 100644
--- a/tests/Integration/Schema/Directives/BuilderDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/BuilderDirectiveTest.php
@@ -28,13 +28,13 @@ public function testCallsCustomBuilderMethod(): void
 
         factory(User::class, 2)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(limit: 1) {
                 id
             }
         }
-        ')->assertJsonCount(1, 'data.users');
+        GRAPHQL)->assertJsonCount(1, 'data.users');
     }
 
     public function testCallsCustomBuilderMethodOnFieldCheckWithArgs(): void
@@ -65,13 +65,13 @@ public function testCallsCustomBuilderMethodOnFieldCheckWithArgs(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(arg1: "Hello", arg2: "World") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testCallsCustomBuilderMethodOnFieldCheckWithoutArgs(): void
@@ -100,13 +100,13 @@ public function testCallsCustomBuilderMethodOnFieldCheckWithoutArgs(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testCallsCustomBuilderMethodOnFieldWithValue(): void
@@ -124,13 +124,13 @@ public function testCallsCustomBuilderMethodOnFieldWithValue(): void
 
         factory(User::class, 2)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
             }
         }
-        ')->assertJsonCount(1, 'data.users');
+        GRAPHQL)->assertJsonCount(1, 'data.users');
     }
 
     public function testCallsCustomBuilderMethodOnFieldWithoutValue(): void
@@ -147,13 +147,13 @@ public function testCallsCustomBuilderMethodOnFieldWithoutValue(): void
 
         factory(User::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
             }
         }
-        ')->assertJsonCount(2, 'data.users');
+        GRAPHQL)->assertJsonCount(2, 'data.users');
     }
 
     public function testCallsCustomBuilderMethodOnFieldWithSpecificModel(): void
@@ -194,7 +194,7 @@ public function testCallsCustomBuilderMethodOnFieldWithSpecificModel(): void
             $taskWithOtherName->save();
         }
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 id
@@ -205,7 +205,7 @@ public function testCallsCustomBuilderMethodOnFieldWithSpecificModel(): void
                 }
             }
         }
-        ')
+        GRAPHQL)
             ->assertJsonCount(1, 'data.users.0.tasks.data')
             ->assertJsonCount(1, 'data.users.1.tasks.data');
     }
diff --git a/tests/Integration/Schema/Directives/ConvertEmptyStringsToNullDirectiveTest.php b/tests/Integration/Schema/Directives/ConvertEmptyStringsToNullDirectiveTest.php
index 62710a7396..420ba1619c 100644
--- a/tests/Integration/Schema/Directives/ConvertEmptyStringsToNullDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/ConvertEmptyStringsToNullDirectiveTest.php
@@ -9,19 +9,19 @@ final class ConvertEmptyStringsToNullDirectiveTest extends TestCase
 {
     public function testOnArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String @convertEmptyStringsToNull): String @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): ?string => $args['bar']);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: "")
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => null,
             ],
@@ -30,19 +30,19 @@ public function testOnArgument(): void
 
     public function testOnArgumentWithMatrix(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: [[[String]]] @convertEmptyStringsToNull): [[[String]]] @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): ?array => $args['bar']);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: [[["", null, "baz"]]])
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [[[null, null, 'baz']]],
             ],
@@ -53,7 +53,7 @@ public function testOnField(): void
     {
         $this->mockResolver(static fn ($_, array $args): array => $args);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             foo: String
             bar: [String]!
@@ -69,9 +69,9 @@ public function testOnField(): void
                 qux: Int!
             ): Foo! @convertEmptyStringsToNull @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(
                 foo: ""
@@ -85,7 +85,7 @@ public function testOnField(): void
                 qux
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'foo' => null,
@@ -101,7 +101,7 @@ public function testDoesNotConvertNonNullableArgumentsWhenUsedOnField(): void
     {
         $this->mockResolver(static fn ($_, array $args): array => $args);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             foo: String!
             bar: [String!]!
@@ -115,9 +115,9 @@ public function testDoesNotConvertNonNullableArgumentsWhenUsedOnField(): void
                 baz: [[[String!]]]
             ): Foo! @convertEmptyStringsToNull @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(
                 foo: ""
@@ -129,7 +129,7 @@ public function testDoesNotConvertNonNullableArgumentsWhenUsedOnField(): void
                 baz
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'foo' => '',
@@ -142,19 +142,19 @@ public function testDoesNotConvertNonNullableArgumentsWhenUsedOnField(): void
 
     public function testConvertsNonNullableArgumentsWhenUsedOnArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String! @convertEmptyStringsToNull): String @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): ?string => $args['bar']);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: "")
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => null,
             ],
@@ -163,25 +163,25 @@ public function testConvertsNonNullableArgumentsWhenUsedOnArgument(): void
 
     public function testConvertsEmptyStringToNullWithFieldDirective(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String): FooResponse
                 @convertEmptyStringsToNull
-                @field(resolver: "Tests\\\Utils\\\Mutations\\\ReturnReceivedInput")
+                @field(resolver: "Tests\\Utils\\Mutations\\ReturnReceivedInput")
         }
 
         type FooResponse {
             bar: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: "") {
                 bar
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'bar' => null,
@@ -196,24 +196,24 @@ public function testConvertsEmptyStringToNullWithGlobalFieldMiddleware(): void
             ConvertEmptyStringsToNullDirective::class,
         ]]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String): FooResponse
-                @field(resolver: "Tests\\\Utils\\\Mutations\\\ReturnReceivedInput")
+                @field(resolver: "Tests\\Utils\\Mutations\\ReturnReceivedInput")
         }
 
         type FooResponse {
             bar: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: "") {
                 bar
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'bar' => null,
@@ -224,11 +224,11 @@ public function testConvertsEmptyStringToNullWithGlobalFieldMiddleware(): void
 
     public function testConvertsEmptyStringToNullWithFieldDirectiveAndInputType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: FooInput): FooInputResponse
                 @convertEmptyStringsToNull
-                @field(resolver: "Tests\\\Utils\\\Mutations\\\ReturnReceivedInput")
+                @field(resolver: "Tests\\Utils\\Mutations\\ReturnReceivedInput")
         }
 
         input FooInput {
@@ -242,9 +242,9 @@ public function testConvertsEmptyStringToNullWithFieldDirectiveAndInputType(): v
         type FooResponse {
             bar: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 bar: ""
@@ -254,7 +254,7 @@ public function testConvertsEmptyStringToNullWithFieldDirectiveAndInputType(): v
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'input' => [
@@ -271,10 +271,10 @@ public function testConvertsEmptyStringToNullWithGlobalFieldMiddlewareAndInputTy
             ConvertEmptyStringsToNullDirective::class,
         ]]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: FooInput): FooInputResponse
-                @field(resolver: "Tests\\\Utils\\\Mutations\\\ReturnReceivedInput")
+                @field(resolver: "Tests\\Utils\\Mutations\\ReturnReceivedInput")
         }
 
         input FooInput {
@@ -288,9 +288,9 @@ public function testConvertsEmptyStringToNullWithGlobalFieldMiddlewareAndInputTy
         type FooResponse {
             bar: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 bar: ""
@@ -300,7 +300,7 @@ public function testConvertsEmptyStringToNullWithGlobalFieldMiddlewareAndInputTy
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'input' => [
diff --git a/tests/Integration/Schema/Directives/CountDirectiveDBTest.php b/tests/Integration/Schema/Directives/CountDirectiveDBTest.php
index 2b0bccd580..9d559eb149 100644
--- a/tests/Integration/Schema/Directives/CountDirectiveDBTest.php
+++ b/tests/Integration/Schema/Directives/CountDirectiveDBTest.php
@@ -15,35 +15,35 @@ final class CountDirectiveDBTest extends DBTestCase
 {
     public function testRequiresARelationOrModelArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks: Int @count
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks
         }
-        ');
+        GRAPHQL);
     }
 
     public function testCountModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks_count: Int @count(model: "Task")
         }
-        ';
+        GRAPHQL;
 
         factory(Task::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks_count
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'tasks_count' => 3,
             ],
@@ -52,11 +52,11 @@ public function testCountModel(): void
 
     public function testCountModelWithScopes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             completed_tasks: Int @count(model: "Task", scopes: ["completed"])
         }
-        ';
+        GRAPHQL;
 
         factory(Task::class, 3)->create();
         $completed = factory(Task::class, 2)->make();
@@ -65,11 +65,11 @@ public function testCountModelWithScopes(): void
             $task->save();
         });
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             completed_tasks
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'completed_tasks' => 2,
             ],
@@ -78,7 +78,7 @@ public function testCountModelWithScopes(): void
 
     public function testCountRelationAndEagerLoadsTheCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!] @all
         }
@@ -86,7 +86,7 @@ public function testCountRelationAndEagerLoadsTheCount(): void
         type User {
             tasks_count: Int @count(relation: "tasks")
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 3)->create()
             ->each(static function (User $user, int $index): void {
@@ -98,13 +98,13 @@ public function testCountRelationAndEagerLoadsTheCount(): void
             });
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     tasks_count
                 }
             }
-            ')->assertExactJson([
+            GRAPHQL)->assertExactJson([
                 'data' => [
                     'users' => [
                         [
@@ -124,7 +124,7 @@ public function testCountRelationAndEagerLoadsTheCount(): void
 
     public function testCountRelationThatIsNotSuffixedWithCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User! @first
         }
@@ -132,7 +132,7 @@ public function testCountRelationThatIsNotSuffixedWithCount(): void
         type User {
             tasks: Int @count(relation: "tasks")
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -142,13 +142,13 @@ public function testCountRelationThatIsNotSuffixedWithCount(): void
             $task->save();
         });
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => [
                     'tasks' => 3,
@@ -159,7 +159,7 @@ public function testCountRelationThatIsNotSuffixedWithCount(): void
 
     public function testCountRelationWithScopesApplied(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -167,7 +167,7 @@ public function testCountRelationWithScopesApplied(): void
         type User {
             completed_tasks: Int! @count(relation: "tasks", scopes: ["completed"])
         }
-        ';
+        GRAPHQL;
 
         /** @var User $user */
         $user = factory(User::class)->create();
@@ -182,13 +182,13 @@ public function testCountRelationWithScopesApplied(): void
         $completedTask->user()->associate($user);
         $completedTask->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 completed_tasks
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => [
                     'completed_tasks' => 1,
@@ -199,7 +199,7 @@ public function testCountRelationWithScopesApplied(): void
 
     public function testCountPolymorphicRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             activity: [Activity!] @all
         }
@@ -220,7 +220,7 @@ public function testCountPolymorphicRelation(): void
             id: ID
             content: ActivityContent! @morphTo
         }
-        ';
+        GRAPHQL;
 
         /** @var User $user */
         $user = factory(User::class)->create();
@@ -265,7 +265,7 @@ public function testCountPolymorphicRelation(): void
                 factory(Image::class, 4)->make(),
             );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             activity {
                 id
@@ -284,7 +284,7 @@ public function testCountPolymorphicRelation(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'activity' => [
                     [
@@ -320,17 +320,17 @@ public function testResolveCountByModel(): void
     {
         factory(User::class)->times(3)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: Int! @count(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => 3,
             ],
@@ -348,7 +348,7 @@ public function testResolveCountByRelation(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             taskCount: Int! @count(relation: "tasks")
         }
@@ -356,15 +356,15 @@ public function testResolveCountByRelation(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 taskCount
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'taskCount' => 4,
@@ -391,7 +391,7 @@ public function testResolveRelationItemsAndCount(): void
 
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany
             taskCount: Int! @count(relation: "tasks")
@@ -404,9 +404,9 @@ public function testResolveRelationItemsAndCount(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks {
@@ -415,7 +415,7 @@ public function testResolveRelationItemsAndCount(): void
                 taskCount
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -434,11 +434,11 @@ public function testResolveRelationItemsAndCount(): void
 
     public function testCountModelWithColumns(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks: Int @count(model: "Task", columns: ["difficulty"])
         }
-        ';
+        GRAPHQL;
 
         $notNull = factory(Task::class)->make();
         $this->assertInstanceOf(Task::class, $notNull);
@@ -450,11 +450,11 @@ public function testCountModelWithColumns(): void
         $notNull->difficulty = 2;
         $notNull->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'tasks' => 1,
             ],
@@ -463,11 +463,11 @@ public function testCountModelWithColumns(): void
 
     public function testCountModelWithColumnsAndDistinct(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks: Int @count(model: "Task", distinct: true, columns: ["difficulty"])
         }
-        ';
+        GRAPHQL;
         foreach (factory(Task::class, 2)->make() as $task) {
             $this->assertInstanceOf(Task::class, $task);
             $task->difficulty = 1;
@@ -479,11 +479,11 @@ public function testCountModelWithColumnsAndDistinct(): void
         $other->difficulty = 2;
         $other->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'tasks' => 2,
             ],
diff --git a/tests/Integration/Schema/Directives/CreateDirectiveTest.php b/tests/Integration/Schema/Directives/CreateDirectiveTest.php
index a0ca489968..e50936dfc6 100644
--- a/tests/Integration/Schema/Directives/CreateDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/CreateDirectiveTest.php
@@ -13,7 +13,7 @@ final class CreateDirectiveTest extends DBTestCase
 {
     public function testCreateFromFieldArguments(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -22,16 +22,16 @@ public function testCreateFromFieldArguments(): void
         type Mutation {
             createCompany(name: String): Company @create
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createCompany(name: "foo") {
                 id
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createCompany' => [
                     'id' => '1',
@@ -43,7 +43,7 @@ public function testCreateFromFieldArguments(): void
 
     public function testCreateFromInputObject(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -56,9 +56,9 @@ public function testCreateFromInputObject(): void
         input CreateCompanyInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createCompany(input: {
                 name: "foo"
@@ -67,7 +67,7 @@ public function testCreateFromInputObject(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createCompany' => [
                     'id' => '1',
@@ -79,7 +79,7 @@ public function testCreateFromInputObject(): void
 
     public function testCreatesAnEntryWithDatabaseDefaultsAndReturnsItImmediately(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             createTag(name: String): Tag @create
         }
@@ -88,16 +88,16 @@ public function testCreatesAnEntryWithDatabaseDefaultsAndReturnsItImmediately():
             name: String!
             default_string: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTag(name: "foobar") {
                 name
                 default_string
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTag' => [
                     'name' => 'foobar',
@@ -117,7 +117,7 @@ public function testDoesNotCreateWithFailingRelationship(): void
         $config = $this->app->make(ConfigRepository::class);
         $config->set('app.debug', false);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -146,9 +146,9 @@ public function testDoesNotCreateWithFailingRelationship(): void
             name: String
             user: ID
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -166,7 +166,7 @@ public function testDoesNotCreateWithFailingRelationship(): void
                 }
             }
         }
-        ')
+        GRAPHQL)
             ->assertJson([
                 'data' => [
                     'createUser' => null,
@@ -188,7 +188,7 @@ public function testCreatesOnPartialFailureWithTransactionsDisabled(): void
         $config->set('app.debug', false);
         $config->set('lighthouse.transactional_mutations', false);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -217,9 +217,9 @@ public function testCreatesOnPartialFailureWithTransactionsDisabled(): void
             name: String
             user: ID
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -237,7 +237,7 @@ public function testCreatesOnPartialFailureWithTransactionsDisabled(): void
                 }
             }
         }
-        ')
+        GRAPHQL)
             // TODO allow partial success
 //            ->assertJson([
 //                'data' => [
@@ -254,7 +254,7 @@ public function testCreatesOnPartialFailureWithTransactionsDisabled(): void
 
     public function testDoesNotFailWhenPropertyNameMatchesModelsNativeMethods(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -284,9 +284,9 @@ public function testDoesNotFailWhenPropertyNameMatchesModelsNativeMethods(): voi
             name: String
             guard: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -302,7 +302,7 @@ public function testDoesNotFailWhenPropertyNameMatchesModelsNativeMethods(): voi
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'tasks' => [
@@ -317,7 +317,7 @@ public function testDoesNotFailWhenPropertyNameMatchesModelsNativeMethods(): voi
 
     public function testNestedArgResolverHasMany(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             createUser(input: CreateUserInput! @spread): User @create
         }
@@ -339,9 +339,9 @@ public function testNestedArgResolverHasMany(): void
         input CreateTaskInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -355,7 +355,7 @@ public function testNestedArgResolverHasMany(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'createUser' => [
                     'name' => 'foo',
@@ -371,7 +371,7 @@ public function testNestedArgResolverHasMany(): void
 
     public function testNestedArgResolverForOptionalBelongsTo(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             createTask(input: CreateTaskInput! @spread): Task @create
         }
@@ -393,9 +393,9 @@ public function testNestedArgResolverForOptionalBelongsTo(): void
         input CreateUserInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "task"
@@ -409,7 +409,7 @@ public function testNestedArgResolverForOptionalBelongsTo(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'createTask' => [
                     'name' => 'task',
@@ -423,7 +423,7 @@ public function testNestedArgResolverForOptionalBelongsTo(): void
 
     public function testCreateTwice(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -451,9 +451,9 @@ public function testCreateTwice(): void
         input CreateTaskInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -466,7 +466,7 @@ public function testCreateTwice(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'name' => 'foo',
@@ -474,7 +474,7 @@ public function testCreateTwice(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "bar"
@@ -487,7 +487,7 @@ public function testCreateTwice(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'name' => 'bar',
@@ -498,7 +498,7 @@ public function testCreateTwice(): void
 
     public function testCreateTwiceWithCreateDirective(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -522,9 +522,9 @@ public function testCreateTwiceWithCreateDirective(): void
         input CreateTaskInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(input: {
                 name: "foo"
@@ -543,7 +543,7 @@ public function testCreateTwiceWithCreateDirective(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createUser' => [
                     'name' => 'foo',
@@ -564,7 +564,7 @@ public function testTurnOnMassAssignment(): void
     {
         config(['lighthouse.force_fill' => false]);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -572,16 +572,16 @@ public function testTurnOnMassAssignment(): void
         type Mutation {
             createCompany(name: String): Company @create
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(MassAssignmentException::class);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createCompany(name: "foo") {
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/CreateManyDirectiveTest.php b/tests/Integration/Schema/Directives/CreateManyDirectiveTest.php
index b211f163b2..246ab13a3d 100644
--- a/tests/Integration/Schema/Directives/CreateManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/CreateManyDirectiveTest.php
@@ -8,7 +8,7 @@ final class CreateManyDirectiveTest extends DBTestCase
 {
     public function testCreateFromFieldArguments(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -21,9 +21,9 @@ public function testCreateFromFieldArguments(): void
         type Mutation {
             createCompanies(inputs: [CreateCompanyInput!]!): [Company!]! @createMany
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createCompanies(inputs: [
                 {
@@ -37,7 +37,7 @@ public function testCreateFromFieldArguments(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createCompanies' => [
                     [
diff --git a/tests/Integration/Schema/Directives/DeleteDirectiveTest.php b/tests/Integration/Schema/Directives/DeleteDirectiveTest.php
index de9f398106..8b23164f54 100644
--- a/tests/Integration/Schema/Directives/DeleteDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/DeleteDirectiveTest.php
@@ -17,7 +17,7 @@ public function testDeletesUserAndReturnsIt(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -25,15 +25,15 @@ public function testDeletesUserAndReturnsIt(): void
         type Mutation {
             deleteUser(id: ID! @whereKey): User @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             deleteUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertJson([
             'data' => [
@@ -48,7 +48,7 @@ public function testDeletesUserAndReturnsIt(): void
 
     public function testDeleteNotFound(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -56,15 +56,15 @@ public function testDeleteNotFound(): void
         type Mutation {
             deleteUser(id: ID! @whereKey): User @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             deleteUser(id: "non-existing") {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'deleteUser' => null,
             ],
@@ -76,7 +76,7 @@ public function testDeletesMultipleUsersByIDAndReturnsThem(): void
         $users = factory(User::class, 2)->create();
         $this->assertInstanceOf(EloquentCollection::class, $users);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -84,15 +84,15 @@ public function testDeletesMultipleUsersByIDAndReturnsThem(): void
         type Mutation {
             deleteUsers(ids: [ID!]! @whereKey): [User!]! @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($ids: [ID!]!) {
             deleteUsers(ids: $ids) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'ids' => $users->pluck('id'),
         ])->assertJsonCount(2, 'data.deleteUsers');
 
@@ -111,7 +111,7 @@ public function testDeleteByNonPrimaryKey(): void
         $bar->name = 'bar';
         $bar->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -119,15 +119,15 @@ public function testDeleteByNonPrimaryKey(): void
         type Mutation {
             deleteUsers(name: String! @eq): [User!]! @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($name: String!) {
             deleteUsers(name: $name) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'name' => $foo->name,
         ])->assertJson([
             'data' => [
@@ -154,7 +154,7 @@ public function testDeleteWithScopes(): void
         $unnamed->name = null;
         $unnamed->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -162,15 +162,15 @@ public function testDeleteWithScopes(): void
         type Mutation {
             deleteUser(id: ID! @whereKey): User @delete(scopes: ["named"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             deleteUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $named->id,
         ])->assertJson([
             'data' => [
@@ -180,13 +180,13 @@ public function testDeleteWithScopes(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             deleteUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $unnamed->id,
         ])->assertJson([
             'data' => [
@@ -197,7 +197,7 @@ public function testDeleteWithScopes(): void
 
     public function testDeletesMultipleNonExisting(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -205,15 +205,15 @@ public function testDeletesMultipleNonExisting(): void
         type Mutation {
             deleteUsers(ids: [ID!]! @whereKey): [User!]! @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             deleteUsers(ids: ["non-existing"]) {
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'deleteUsers' => [],
             ],
@@ -222,7 +222,7 @@ public function testDeletesMultipleNonExisting(): void
 
     public function testDeletesMultipleEmptyInput(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -230,15 +230,15 @@ public function testDeletesMultipleEmptyInput(): void
         type Mutation {
             deleteUsers(ids: [ID!]! @whereKey): [User!]! @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             deleteUsers(ids: []) {
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'deleteUsers' => [],
             ],
@@ -247,7 +247,7 @@ public function testDeletesMultipleEmptyInput(): void
 
     public function testDeleteRequiresAtLeastOneArgument(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -255,20 +255,20 @@ public function testDeleteRequiresAtLeastOneArgument(): void
         type Mutation {
             deleteUser(id: ID @whereKey, email: String @eq): User @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             deleteUser {
                 id
             }
         }
-        ')->assertGraphQLError(ModifyModelExistenceDirective::wouldModifyAll());
+        GRAPHQL)->assertGraphQLError(ModifyModelExistenceDirective::wouldModifyAll());
     }
 
     public function testDoesNotAcceptArgumentWithoutArgBuilderDirective(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -276,22 +276,22 @@ public function testDoesNotAcceptArgumentWithoutArgBuilderDirective(): void
         type Mutation {
             deleteUser(id: ID): User @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             deleteUser(id: 1) {
                 id
             }
         }
-        ')->assertGraphQLError(ModifyModelExistenceDirective::wouldModifyAll());
+        GRAPHQL)->assertGraphQLError(ModifyModelExistenceDirective::wouldModifyAll());
     }
 
     public function testRequiresRelationWhenUsingAsArgResolver(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(deleteTasks: Tasks @delete): User @update
         }
@@ -299,7 +299,7 @@ public function testRequiresRelationWhenUsingAsArgResolver(): void
         type User {
             id: ID!
         }
-        ' . self::PLACEHOLDER_QUERY);
+        GRAPHQL . self::PLACEHOLDER_QUERY);
     }
 
     public function testUseNestedArgResolverDelete(): void
@@ -314,7 +314,7 @@ public function testUseNestedArgResolverDelete(): void
             $task->save();
         }
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(
                 id: ID
@@ -330,9 +330,9 @@ public function testUseNestedArgResolverDelete(): void
         type Task {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!, $deleteTasks: [ID!]!) {
             updateUser(id: $id, deleteTasks: $deleteTasks) {
                 id
@@ -341,7 +341,7 @@ public function testUseNestedArgResolverDelete(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
             'deleteTasks' => [$tasks[1]->id],
         ])->assertExactJson([
@@ -368,7 +368,7 @@ public function testDeleteHasOneThroughNestedArgResolver(): void
         $post->task()->associate($task);
         $post->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateTask(
                 id: ID
@@ -384,9 +384,9 @@ public function testDeleteHasOneThroughNestedArgResolver(): void
         type Post {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             updateTask(id: $id, deletePost: false) {
                 id
@@ -395,7 +395,7 @@ public function testDeleteHasOneThroughNestedArgResolver(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertExactJson([
             'data' => [
@@ -408,7 +408,7 @@ public function testDeleteHasOneThroughNestedArgResolver(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             updateTask(id: $id, deletePost: true) {
                 id
@@ -417,7 +417,7 @@ public function testDeleteHasOneThroughNestedArgResolver(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertExactJson([
             'data' => [
@@ -441,7 +441,7 @@ public function testDeleteBelongsToThroughNestedArgResolver(): void
         $task->user()->associate($user);
         $task->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateTask(
                 id: ID!
@@ -457,9 +457,9 @@ public function testDeleteBelongsToThroughNestedArgResolver(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             updateTask(id: $id, deleteUser: true) {
                 id
@@ -468,7 +468,7 @@ public function testDeleteBelongsToThroughNestedArgResolver(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $task->id,
         ])->assertExactJson([
             'data' => [
@@ -490,7 +490,7 @@ public function testDeletingReturnsFalseTriggersException(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -498,15 +498,15 @@ public function testDeletingReturnsFalseTriggersException(): void
         type Mutation {
             deleteUser(id: ID! @whereKey): User @delete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             deleteUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertGraphQLError(ModifyModelExistenceDirective::couldNotModify($user));
     }
diff --git a/tests/Integration/Schema/Directives/EnumDirectiveTest.php b/tests/Integration/Schema/Directives/EnumDirectiveTest.php
index f31963b8c1..1d21089b1c 100644
--- a/tests/Integration/Schema/Directives/EnumDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/EnumDirectiveTest.php
@@ -14,7 +14,7 @@ public function testDefinesEnumWithInternalValues(): void
             return 'Not active';
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         enum Status {
             ACTIVE @enum(value: "Active internal")
             INACTIVE @enum(value: "Not active")
@@ -23,14 +23,14 @@ enum Status {
         type Query {
             status(status: Status!): Status! @mock
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 status(status: ACTIVE)
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'status' => 'INACTIVE',
diff --git a/tests/Integration/Schema/Directives/EqDirectiveTest.php b/tests/Integration/Schema/Directives/EqDirectiveTest.php
index 9280ca49d0..325aa9bb82 100644
--- a/tests/Integration/Schema/Directives/EqDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/EqDirectiveTest.php
@@ -12,7 +12,7 @@ public function testAttachEqFilterFromFieldArgument(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -20,16 +20,16 @@ public function testAttachEqFilterFromFieldArgument(): void
         type Query {
             users(id: ID @eq): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID) {
                 users(id: $id) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $users->first()->getKey(),
             ])
             ->assertJsonCount(1, 'data.users');
@@ -39,7 +39,7 @@ public function testAttachEqFilterFromInputObject(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -51,10 +51,10 @@ public function testAttachEqFilterFromInputObject(): void
         input UserInput {
             id: ID @eq
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID) {
                 users(
                     input: {
@@ -64,7 +64,7 @@ public function testAttachEqFilterFromInputObject(): void
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $users->first()->getKey(),
             ])
             ->assertJsonCount(1, 'data.users');
@@ -74,7 +74,7 @@ public function testAttachEqFilterFromInputObjectWithinList(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -86,10 +86,10 @@ public function testAttachEqFilterFromInputObjectWithinList(): void
         input UserInput {
             id: ID @eq
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID) {
                 users(
                     input: [
@@ -101,7 +101,7 @@ public function testAttachEqFilterFromInputObjectWithinList(): void
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $users->first()->getKey(),
             ])
             ->assertJsonCount(1, 'data.users');
@@ -111,24 +111,24 @@ public function testAttachEqFilterFromField(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type User {
             id: ID!
         }
 
         type Query {
-            users: [User!]! @all @eq(key: \"id\", value: {$users->first()->getKey()})
+            users: [User!]! @all @eq(key: "id", value: {$users->first()->getKey()})
         }
-        ";
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(1, 'data.users');
     }
 
@@ -136,7 +136,7 @@ public function testEqOnFieldRequiresValue(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -144,14 +144,14 @@ public function testEqOnFieldRequiresValue(): void
         type Query {
             users: [User!]! @all @eq
         }
-        ');
+        GRAPHQL);
     }
 
     public function testEqOnFieldRequiresKey(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -159,6 +159,6 @@ public function testEqOnFieldRequiresKey(): void
         type Query {
             users: [User!]! @all @eq(value: 3)
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/EventDirectiveTest.php b/tests/Integration/Schema/Directives/EventDirectiveTest.php
index 2f3ad2b50e..dfec5d7f6a 100644
--- a/tests/Integration/Schema/Directives/EventDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/EventDirectiveTest.php
@@ -14,7 +14,7 @@ public function testDispatchesAnEvent(): void
             CompanyWasCreatedEvent::class,
         ]);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -22,18 +22,18 @@ public function testDispatchesAnEvent(): void
 
         type Mutation {
             createCompany(name: String): Company @create
-                @event(dispatch: "Tests\\\\Integration\\\\Schema\\\\Directives\\\\Fixtures\\\\CompanyWasCreatedEvent")
+                @event(dispatch: "Tests\\Integration\\Schema\\Directives\\Fixtures\\CompanyWasCreatedEvent")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createCompany(name: "foo") {
                 id
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createCompany' => [
                     'id' => '1',
diff --git a/tests/Integration/Schema/Directives/FindDirectiveTest.php b/tests/Integration/Schema/Directives/FindDirectiveTest.php
index f96c7a6d5c..02d678066d 100644
--- a/tests/Integration/Schema/Directives/FindDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/FindDirectiveTest.php
@@ -14,7 +14,7 @@ public function testReturnsSingleUser(): void
         $userB = $this->createUserWithName('B');
         $this->createUserWithName('C');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -23,15 +23,15 @@ public function testReturnsSingleUser(): void
         type Query {
             user(id: ID @eq): User @find(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             user(id:{$userB->id}) {
                 name
             }
         }
-        ")->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'user' => [
                 'name' => 'B',
             ],
@@ -43,7 +43,7 @@ public function testDefaultsToFieldTypeIfNoModelIsSupplied(): void
         $userA = $this->createUserWithName('A');
         $this->createUserWithName('B');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -52,15 +52,15 @@ public function testDefaultsToFieldTypeIfNoModelIsSupplied(): void
         type Query {
             user(id: ID @eq): User @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             user(id:{$userA->id}) {
                 name
             }
         }
-        ")->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'name' => 'A',
         ]);
     }
@@ -71,7 +71,7 @@ public function testCannotFetchIfMultipleModelsMatch(): void
         $this->createUserWithName('A');
         $this->createUserWithName('B');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -80,15 +80,15 @@ public function testCannotFetchIfMultipleModelsMatch(): void
         type Query {
             user(name: String @eq): User @find(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(name: "A") {
                 name
             }
         }
-        ')->assertJsonCount(1, 'errors');
+        GRAPHQL)->assertJsonCount(1, 'errors');
     }
 
     public function testUseScopes(): void
@@ -99,7 +99,7 @@ public function testUseScopes(): void
         $this->createUserWithNameAndCompany('A', $companyB);
         $this->createUserWithNameAndCompany('B', $companyA);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             name: String!
         }
@@ -112,16 +112,16 @@ public function testUseScopes(): void
         type Query {
             user(name: String @eq, company: String!): User @find(model: "User" scopes: [companyName])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(name: "A" company: "CompanyA") {
                 id
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'id' => $userA->id,
@@ -133,7 +133,7 @@ public function testUseScopes(): void
 
     public function testReturnsAnEmptyObjectWhenTheModelIsNotFound(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -142,16 +142,16 @@ public function testReturnsAnEmptyObjectWhenTheModelIsNotFound(): void
         type Query {
             user(name: String @eq): User @find(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(name: "A") {
                 id
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => null,
             ],
@@ -164,7 +164,7 @@ public function testReturnsCustomAttributes(): void
         $this->assertInstanceOf(Company::class, $company);
         $user = $this->createUserWithNameAndCompany('A', $company);
 
-        $this->schema = '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -174,9 +174,9 @@ public function testReturnsCustomAttributes(): void
         type Query {
             user(id: ID @eq): User @find(model: "User")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL("
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             user(id: {$user->id}) {
                 id
@@ -184,7 +184,7 @@ public function testReturnsCustomAttributes(): void
                 companyName
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'id' => (string) $user->id,
diff --git a/tests/Integration/Schema/Directives/FirstDirectiveTest.php b/tests/Integration/Schema/Directives/FirstDirectiveTest.php
index 3156d8b623..5a8b4a7787 100644
--- a/tests/Integration/Schema/Directives/FirstDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/FirstDirectiveTest.php
@@ -9,7 +9,7 @@ final class FirstDirectiveTest extends DBTestCase
 {
     public function testReturnsASingleUser(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -18,7 +18,7 @@ public function testReturnsASingleUser(): void
         type Query {
             user(id: ID @eq): User @first(model: "User")
         }
-        ';
+        GRAPHQL;
 
         $userA = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userA);
@@ -29,13 +29,13 @@ public function testReturnsASingleUser(): void
         $userC = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userC);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $userB->id,
         ])->assertJson([
             'data' => [
@@ -48,7 +48,7 @@ public function testReturnsASingleUser(): void
 
     public function testReturnsASingleUserWhenMultiplesMatch(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -57,7 +57,7 @@ public function testReturnsASingleUserWhenMultiplesMatch(): void
         type Query {
             user(name: String @eq): User @first(model: "User")
         }
-        ';
+        GRAPHQL;
 
         $userA1 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userA1);
@@ -74,13 +74,13 @@ public function testReturnsASingleUserWhenMultiplesMatch(): void
         $userB->name = 'B';
         $userB->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(name: "A") {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'id' => $userA1->id,
diff --git a/tests/Integration/Schema/Directives/HasManyDirectiveTest.php b/tests/Integration/Schema/Directives/HasManyDirectiveTest.php
index cc8783fdf7..ae50a98e17 100644
--- a/tests/Integration/Schema/Directives/HasManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/HasManyDirectiveTest.php
@@ -15,7 +15,7 @@ final class HasManyDirectiveTest extends DBTestCase
 {
     public function testQueryHasManyRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany
         }
@@ -28,7 +28,7 @@ public function testQueryHasManyRelationship(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -48,7 +48,7 @@ public function testQueryHasManyRelationship(): void
         $this->assertSame(4, $tasksWithoutGlobalScope);
 
         // Ensure global scopes are respected here
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks {
@@ -56,12 +56,12 @@ public function testQueryHasManyRelationship(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.user.tasks');
+        GRAPHQL)->assertJsonCount(3, 'data.user.tasks');
     }
 
     public function testHasManyWithRenamedModel(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             foos: [Foo!]! @hasMany(relation: "tasks")
         }
@@ -73,7 +73,7 @@ public function testHasManyWithRenamedModel(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -81,7 +81,7 @@ public function testHasManyWithRenamedModel(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 foos {
@@ -89,12 +89,12 @@ public function testHasManyWithRenamedModel(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.user.foos');
+        GRAPHQL)->assertJsonCount(3, 'data.user.foos');
     }
 
     public function testQueryHasManyWithCondition(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks(
                 id: ID! @eq
@@ -108,7 +108,7 @@ public function testQueryHasManyWithCondition(): void
         type Query {
             user: User! @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -120,7 +120,7 @@ public function testQueryHasManyWithCondition(): void
         $this->assertInstanceOf(Task::class, $firstTask);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 user {
                     tasks(id: $id) {
@@ -128,7 +128,7 @@ public function testQueryHasManyWithCondition(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $firstTask->id,
             ])
             ->assertJsonCount(1, 'data.user.tasks');
@@ -136,7 +136,7 @@ public function testQueryHasManyWithCondition(): void
 
     public function testQueryHasManyWithConditionInDifferentAliases(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks(
                 id: ID! @eq
@@ -150,7 +150,7 @@ public function testQueryHasManyWithConditionInDifferentAliases(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user1 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user1);
@@ -171,7 +171,7 @@ public function testQueryHasManyWithConditionInDifferentAliases(): void
         $this->assertInstanceOf(Task::class, $lastTask);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($firstId: ID!, $lastId: ID!) {
                 users {
                     firstTasks: tasks(id: $firstId) {
@@ -182,7 +182,7 @@ public function testQueryHasManyWithConditionInDifferentAliases(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'firstId' => $firstTask->id,
                 'lastId' => $lastTask->id,
             ])
@@ -212,7 +212,7 @@ public function testQueryHasManyWithConditionInDifferentAliases(): void
 
     public function testQueryPaginatedHasManyWithConditionInDifferentAliases(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks(
                 id: ID! @eq
@@ -226,7 +226,7 @@ public function testQueryPaginatedHasManyWithConditionInDifferentAliases(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user1 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user1);
@@ -247,7 +247,7 @@ public function testQueryPaginatedHasManyWithConditionInDifferentAliases(): void
         $this->assertInstanceOf(Task::class, $lastTask);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($firstId: ID!, $lastId: ID!) {
                 users {
                     firstTasks: tasks(id: $firstId) {
@@ -262,7 +262,7 @@ public function testQueryPaginatedHasManyWithConditionInDifferentAliases(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'firstId' => $firstTask->id,
                 'lastId' => $lastTask->id,
             ])
@@ -300,7 +300,7 @@ public function testQueryPaginatedHasManyWithConditionInDifferentAliases(): void
 
     public function testQueryPaginatedHasManyFirst0(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             tasks: [Task!]! @hasMany(type: PAGINATOR)
@@ -313,7 +313,7 @@ public function testQueryPaginatedHasManyFirst0(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -323,7 +323,7 @@ public function testQueryPaginatedHasManyFirst0(): void
         $user->tasks()->saveMany($tasks);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     id
@@ -337,7 +337,7 @@ public function testQueryPaginatedHasManyFirst0(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'users' => [
@@ -357,7 +357,7 @@ public function testQueryPaginatedHasManyFirst0(): void
 
     public function testQueryPaginatedHasManyWithNonUniqueForeignKey(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             roles: [RoleUser!]! @hasMany(relation: "roles", type: PAGINATOR, defaultCount: 10)
         }
@@ -371,7 +371,7 @@ public function testQueryPaginatedHasManyWithNonUniqueForeignKey(): void
         type Query {
             posts: [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -394,7 +394,7 @@ public function testQueryPaginatedHasManyWithNonUniqueForeignKey(): void
         $this->assertCount(3, $user->roles);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query {
                 posts {
                     roles {
@@ -406,7 +406,7 @@ public function testQueryPaginatedHasManyWithNonUniqueForeignKey(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'posts' => [
@@ -459,7 +459,7 @@ public function testQueryPaginatedHasManyWithNonUniqueForeignKey(): void
 
     public function testCallsScopeWithResolverArgs(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks(foo: Int): [Task!]! @hasMany(scopes: ["foo"])
         }
@@ -472,7 +472,7 @@ public function testCallsScopeWithResolverArgs(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -480,7 +480,7 @@ public function testCallsScopeWithResolverArgs(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(foo: 2) {
@@ -488,7 +488,7 @@ public function testCallsScopeWithResolverArgs(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.user.tasks');
+        GRAPHQL)->assertJsonCount(2, 'data.user.tasks');
     }
 
     /** @dataProvider batchloadRelations */
@@ -507,7 +507,7 @@ public function testQueryHasManyPaginator(bool $batchloadRelations): void
             factory(Post::class, 3)->make(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR)
             posts: [Post!]! @hasMany(type: SIMPLE)
@@ -524,10 +524,10 @@ public function testQueryHasManyPaginator(bool $batchloadRelations): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks(first: 2) {
@@ -550,7 +550,7 @@ public function testQueryHasManyPaginator(bool $batchloadRelations): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'user' => [
@@ -581,7 +581,7 @@ public function testDoesNotRequireModelClassForPaginatedHasMany(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [NotTheModelNameTask!]! @hasMany(type: PAGINATOR)
         }
@@ -593,9 +593,9 @@ public function testDoesNotRequireModelClassForPaginatedHasMany(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 2) {
@@ -610,7 +610,7 @@ public function testDoesNotRequireModelClassForPaginatedHasMany(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -635,7 +635,7 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR, maxCount: 3)
         }
@@ -647,10 +647,10 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks(first: 5) {
@@ -660,7 +660,7 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(PaginationArgs::requestedTooManyItems(3, 5));
     }
 
@@ -674,7 +674,7 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR, maxCount: null)
         }
@@ -686,10 +686,10 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     tasks(first: 5) {
@@ -699,7 +699,7 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree();
     }
 
@@ -711,7 +711,7 @@ public function testRejectsPaginationWithNegativeCount(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID
             tasks: [Task!] @hasMany(type: PAGINATOR)
@@ -724,10 +724,10 @@ public function testRejectsPaginationWithNegativeCount(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     id
@@ -738,7 +738,7 @@ public function testRejectsPaginationWithNegativeCount(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(PaginationArgs::requestedLessThanZeroItems(-1));
     }
 
@@ -752,7 +752,7 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: CONNECTION, maxCount: 3)
         }
@@ -764,9 +764,9 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 5) {
@@ -778,7 +778,7 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(3, 5),
@@ -796,7 +796,7 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR)
         }
@@ -808,9 +808,9 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 3) {
@@ -820,7 +820,7 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(2, 3),
@@ -838,7 +838,7 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: CONNECTION)
         }
@@ -850,9 +850,9 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 3) {
@@ -864,7 +864,7 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(2, 3),
@@ -880,7 +880,7 @@ public function testQueryHasManyPaginatorWithADefaultCount(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR, defaultCount: 2)
         }
@@ -892,9 +892,9 @@ public function testQueryHasManyPaginatorWithADefaultCount(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks {
@@ -909,7 +909,7 @@ public function testQueryHasManyPaginatorWithADefaultCount(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -932,7 +932,7 @@ public function testQueryHasManyRelayConnection(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: CONNECTION)
         }
@@ -944,9 +944,9 @@ public function testQueryHasManyRelayConnection(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 2) {
@@ -961,7 +961,7 @@ public function testQueryHasManyRelayConnection(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -982,7 +982,7 @@ public function testQueryHasManyRelayConnectionWithADefaultCount(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: CONNECTION, defaultCount: 2)
         }
@@ -994,9 +994,9 @@ public function testQueryHasManyRelayConnectionWithADefaultCount(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks {
@@ -1011,7 +1011,7 @@ public function testQueryHasManyRelayConnectionWithADefaultCount(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -1032,7 +1032,7 @@ public function testQueryHasManyNestedRelationships(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: CONNECTION)
         }
@@ -1045,9 +1045,9 @@ public function testQueryHasManyNestedRelationships(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 2) {
@@ -1071,7 +1071,7 @@ public function testQueryHasManyNestedRelationships(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -1100,7 +1100,7 @@ public function testQueryHasManySelfReferencingRelationships(): void
         $post3->parent()->associate($post2);
         $post3->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: Int!
             parent: Post @belongsTo
@@ -1109,9 +1109,9 @@ public function testQueryHasManySelfReferencingRelationships(): void
         type Query {
             posts: [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts {
                 id
@@ -1123,7 +1123,7 @@ public function testQueryHasManySelfReferencingRelationships(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'posts' => [
                     [
@@ -1154,7 +1154,7 @@ public function testQueryHasManySelfReferencingRelationships(): void
     public function testQueryHasManyPaginatorBeforeQuery(): void
     {
         // BeforeQuery
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: Int!
             tasks: [Task!]! @hasMany(type: PAGINATOR)
@@ -1168,7 +1168,7 @@ public function testQueryHasManyPaginatorBeforeQuery(): void
             user(id: ID! @eq): User @find
             tasks: [Task!]! @paginate
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -1176,7 +1176,7 @@ public function testQueryHasManyPaginatorBeforeQuery(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 2) {
                 data {
@@ -1184,13 +1184,13 @@ public function testQueryHasManyPaginatorBeforeQuery(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks.data');
     }
 
     public function testQueryHasManyPaginatorAfterQuery(): void
     {
         // AfterQuery
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @eq): User @find
             tasks: [Task!]! @paginate
@@ -1204,7 +1204,7 @@ public function testQueryHasManyPaginatorAfterQuery(): void
         type Task {
             id: Int!
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -1212,7 +1212,7 @@ public function testQueryHasManyPaginatorAfterQuery(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 2) {
                 data{
@@ -1220,13 +1220,13 @@ public function testQueryHasManyPaginatorAfterQuery(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks.data');
     }
 
     public function testQueryHasManyNoTypePaginator(): void
     {
         // AfterQuery
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(id: ID! @eq): User @find
             tasks: [Task!]! @paginate
@@ -1240,7 +1240,7 @@ public function testQueryHasManyNoTypePaginator(): void
         type Task {
             id: Int!
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -1248,7 +1248,7 @@ public function testQueryHasManyNoTypePaginator(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 2) {
                 data{
@@ -1256,12 +1256,12 @@ public function testQueryHasManyNoTypePaginator(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks.data');
     }
 
     public function testHasManyWithModelAndPaginatedRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany(type: PAGINATOR) @can(ability: "adminOnly")
         }
@@ -1273,7 +1273,7 @@ public function testHasManyWithModelAndPaginatedRelation(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user);
@@ -1285,7 +1285,7 @@ public function testHasManyWithModelAndPaginatedRelation(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 3) {
@@ -1295,12 +1295,12 @@ public function testHasManyWithModelAndPaginatedRelation(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.user.tasks.data');
+        GRAPHQL)->assertJsonCount(3, 'data.user.tasks.data');
     }
 
     public function testHasManyWithRenamedModelAndPaginatedRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             foos: [Foo!]! @hasMany(type: PAGINATOR, relation: "tasks") @can(ability: "adminOnly")
         }
@@ -1312,7 +1312,7 @@ public function testHasManyWithRenamedModelAndPaginatedRelation(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user);
@@ -1324,7 +1324,7 @@ public function testHasManyWithRenamedModelAndPaginatedRelation(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 foos(first: 3) {
@@ -1334,12 +1334,12 @@ public function testHasManyWithRenamedModelAndPaginatedRelation(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.user.foos.data');
+        GRAPHQL)->assertJsonCount(3, 'data.user.foos.data');
     }
 
     public function testHasManyWithRenamedModelAndConnection(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             foos: [Foo!]! @hasMany(type: CONNECTION, relation: "tasks") @can(ability: "adminOnly")
         }
@@ -1351,7 +1351,7 @@ public function testHasManyWithRenamedModelAndConnection(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user);
@@ -1363,7 +1363,7 @@ public function testHasManyWithRenamedModelAndConnection(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 foos(first: 3) {
@@ -1375,7 +1375,7 @@ public function testHasManyWithRenamedModelAndConnection(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.user.foos.edges');
+        GRAPHQL)->assertJsonCount(3, 'data.user.foos.edges');
     }
 
     /** @return iterable<array{bool}> */
diff --git a/tests/Integration/Schema/Directives/HasManyThroughDirectiveTest.php b/tests/Integration/Schema/Directives/HasManyThroughDirectiveTest.php
index 60c24257f0..0d18bbb75a 100644
--- a/tests/Integration/Schema/Directives/HasManyThroughDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/HasManyThroughDirectiveTest.php
@@ -12,7 +12,7 @@ final class HasManyThroughDirectiveTest extends DBTestCase
 {
     public function testQueryHasManyThroughRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -24,7 +24,7 @@ public function testQueryHasManyThroughRelationship(): void
         type Query {
             task: Task! @first
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -46,7 +46,7 @@ public function testQueryHasManyThroughRelationship(): void
             $comment->save();
         }
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             task {
                 postComments {
@@ -54,6 +54,6 @@ public function testQueryHasManyThroughRelationship(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.task.postComments');
+        GRAPHQL)->assertJsonCount(2, 'data.task.postComments');
     }
 }
diff --git a/tests/Integration/Schema/Directives/HasOneDirectiveTest.php b/tests/Integration/Schema/Directives/HasOneDirectiveTest.php
index aeb7ed9ed8..41465bdc48 100644
--- a/tests/Integration/Schema/Directives/HasOneDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/HasOneDirectiveTest.php
@@ -17,7 +17,7 @@ public function testQueryHasOneRelationship(): void
         $post = factory(Post::class)->create();
         $this->assertInstanceOf(Post::class, $post);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: Int
         }
@@ -29,9 +29,9 @@ public function testQueryHasOneRelationship(): void
         type Query {
             tasks: [Task!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks {
                 post {
@@ -39,7 +39,7 @@ public function testQueryHasOneRelationship(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'tasks' => [
                     [
diff --git a/tests/Integration/Schema/Directives/HasOneThroughDirectiveTest.php b/tests/Integration/Schema/Directives/HasOneThroughDirectiveTest.php
index fe6849816f..9388ed171e 100644
--- a/tests/Integration/Schema/Directives/HasOneThroughDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/HasOneThroughDirectiveTest.php
@@ -10,7 +10,7 @@ final class HasOneThroughDirectiveTest extends DBTestCase
 {
     public function testQueryHasOneThroughRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks: [Task!]! @all
         }
@@ -24,7 +24,7 @@ public function testQueryHasOneThroughRelationship(): void
             id: ID!
             status: String
         }
-        ';
+        GRAPHQL;
 
         $post = factory(Post::class)->create();
         $this->assertInstanceOf(Post::class, $post);
@@ -34,7 +34,7 @@ public function testQueryHasOneThroughRelationship(): void
         $postStatus->post()->associate($post);
         $postStatus->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks {
                 id
@@ -44,7 +44,7 @@ public function testQueryHasOneThroughRelationship(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'tasks' => [
                     [
diff --git a/tests/Integration/Schema/Directives/InDirectiveTest.php b/tests/Integration/Schema/Directives/InDirectiveTest.php
index c32a91b996..ead5dfe666 100644
--- a/tests/Integration/Schema/Directives/InDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/InDirectiveTest.php
@@ -14,7 +14,7 @@ public function testInIDs(): void
 
         factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -22,18 +22,18 @@ public function testInIDs(): void
         type Query {
             users(ids: [ID!] @in(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user1ID = (string) $user1->id;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [ID!]) {
                 users(ids: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => [$user1ID],
             ])
             ->assertJson([
@@ -51,7 +51,7 @@ public function testExplicitNull(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -59,16 +59,16 @@ public function testExplicitNull(): void
         type Query {
             users(ids: [ID!] @in(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [ID!]) {
                 users(ids: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => null,
             ])
             ->assertJsonCount($users->count(), 'data.users');
@@ -78,7 +78,7 @@ public function testExplicitNullInArray(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -86,16 +86,16 @@ public function testExplicitNullInArray(): void
         type Query {
             users(ids: [ID] @in(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [ID]) {
                 users(ids: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => [null],
             ])
             ->assertJsonCount(0, 'data.users');
@@ -105,7 +105,7 @@ public function testEmptyArray(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -113,16 +113,16 @@ public function testEmptyArray(): void
         type Query {
             users(ids: [ID!] @in(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($ids: [ID!]) {
                 users(ids: $ids) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'ids' => [],
             ])
             ->assertJsonCount(0, 'data.users');
diff --git a/tests/Integration/Schema/Directives/InjectDirectiveDBTest.php b/tests/Integration/Schema/Directives/InjectDirectiveDBTest.php
index 0c79df9e5a..f7ef8e4ec2 100644
--- a/tests/Integration/Schema/Directives/InjectDirectiveDBTest.php
+++ b/tests/Integration/Schema/Directives/InjectDirectiveDBTest.php
@@ -15,7 +15,7 @@ public function testInjectDataFromContextIntoArgs(): void
         $this->mockResolver()
             ->with(null, ['user_id' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: Int!
         }
@@ -25,14 +25,14 @@ public function testInjectDataFromContextIntoArgs(): void
                 @inject(context: "user.id", name: "user_id")
                 @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             me {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/InjectDirectiveTest.php b/tests/Integration/Schema/Directives/InjectDirectiveTest.php
index f4a778803b..70e2ca50f4 100644
--- a/tests/Integration/Schema/Directives/InjectDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/InjectDirectiveTest.php
@@ -12,7 +12,7 @@ public function testCreateFromInputObjectWithDeepInjection(): void
         $user = factory(User::class)->create();
         $this->be($user);
 
-        $this->schema .= '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -30,9 +30,9 @@ public function testCreateFromInputObjectWithDeepInjection(): void
         input CreateTaskInput {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL('
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createTask(input: {
                 name: "foo"
@@ -44,7 +44,7 @@ public function testCreateFromInputObjectWithDeepInjection(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'createTask' => [
                     'id' => '1',
diff --git a/tests/Integration/Schema/Directives/LazyLoadDirectiveTest.php b/tests/Integration/Schema/Directives/LazyLoadDirectiveTest.php
index ab772034f7..895dbc1444 100644
--- a/tests/Integration/Schema/Directives/LazyLoadDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/LazyLoadDirectiveTest.php
@@ -13,22 +13,22 @@ public function testLazyLoadRequiresRelationArgument(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @lazyLoad
         }
-        ');
+        GRAPHQL);
     }
 
     public function testLazyLoadRelationArgumentMustNotBeEmptyList(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @lazyLoad(relations: [])
         }
-        ');
+        GRAPHQL);
     }
 
     public function testLazyLoadRelationsOnConnections(): void
@@ -39,7 +39,7 @@ public function testLazyLoadRelationsOnConnections(): void
         $tasks = factory(Task::class, 3)->make();
         $user->tasks()->saveMany($tasks);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]!
                 @lazyLoad(relations: ["user"])
@@ -54,9 +54,9 @@ public function testLazyLoadRelationsOnConnections(): void
         type Query {
             user: User @first
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasks(first: 1) {
@@ -68,7 +68,7 @@ public function testLazyLoadRelationsOnConnections(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -89,7 +89,7 @@ public function testLazyLoadRelationsOnPaginate(): void
     {
         factory(User::class)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany
             tasksLoaded: Boolean! @method
@@ -102,9 +102,9 @@ public function testLazyLoadRelationsOnPaginate(): void
         type Query {
             users: [User!]! @paginate @lazyLoad(relations: ["tasks"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 1) {
                 data {
@@ -112,7 +112,7 @@ public function testLazyLoadRelationsOnPaginate(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'data' => [
diff --git a/tests/Integration/Schema/Directives/LikeDirectiveTest.php b/tests/Integration/Schema/Directives/LikeDirectiveTest.php
index d12eed57bc..6a1ff7936b 100644
--- a/tests/Integration/Schema/Directives/LikeDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/LikeDirectiveTest.php
@@ -13,7 +13,7 @@ public function testLikeClientsCanPassWildcards(): void
         $this->createUserWithName('Alex');
         $this->createUserWithName('Aaron');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -23,15 +23,15 @@ public function testLikeClientsCanPassWildcards(): void
                 name: String! @like
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(name: "Al%") {
                 name
             }
         }
-        ')->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'users' => [
                 [
                     'name' => 'Alan',
@@ -49,7 +49,7 @@ public function testLikeWithWildcardsInTemplate(): void
         $this->createUserWithName('Alex');
         $this->createUserWithName('Aaron');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -59,15 +59,15 @@ public function testLikeWithWildcardsInTemplate(): void
                 name: String! @like(template: "%{}%")
             ): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(name: "l") {
                 name
             }
         }
-        ')->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'users' => [
                 [
                     'name' => 'Alan',
@@ -86,7 +86,7 @@ public function testLikeClientWildcardsAreEscapedFromTemplate(): void
         $this->createUserWithName('Aar%');
         $this->createUserWithName('Aar%toomuch');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -97,15 +97,15 @@ public function testLikeClientWildcardsAreEscapedFromTemplate(): void
                 name: String! @like(template: "%{}__")
             ): [User!] @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(name: "ar%") {
                 name
             }
         }
-        ')->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'users' => [
                 [
                     'name' => 'Aar%on',
@@ -119,7 +119,7 @@ public function testLikeOnField(): void
         $this->createUserWithName('Alex');
         $this->createUserWithName('Aaron');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -130,15 +130,15 @@ public function testLikeOnField(): void
                 @all
                 @like(key: "name", value: "%ex")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 name
             }
         }
-        ')->assertJsonFragment([
+        GRAPHQL)->assertJsonFragment([
             'users' => [
                 [
                     'name' => 'Alex',
diff --git a/tests/Integration/Schema/Directives/LimitDirectiveTest.php b/tests/Integration/Schema/Directives/LimitDirectiveTest.php
index 9cf29502ae..26d5236744 100644
--- a/tests/Integration/Schema/Directives/LimitDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/LimitDirectiveTest.php
@@ -26,7 +26,7 @@ public function testLimitsResults(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -34,7 +34,7 @@ public function testLimitsResults(): void
         type Query {
             users(limit: Int @limit): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $queries = [];
         DB::listen(static function (QueryExecuted $query) use (&$queries): void {
@@ -42,13 +42,13 @@ public function testLimitsResults(): void
         });
 
         $limit = 1;
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($limit: Int) {
             users(limit: $limit) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'limit' => $limit,
         ])->assertJsonCount($limit, 'data.users');
         $this->assertSame([
@@ -60,7 +60,7 @@ public function testLimitsQueryBuilder(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -68,7 +68,7 @@ public function testLimitsQueryBuilder(): void
         type Query {
             users(limit: Int @limit(builder: true)): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $queries = [];
         DB::listen(static function (QueryExecuted $query) use (&$queries): void {
@@ -76,13 +76,13 @@ public function testLimitsQueryBuilder(): void
         });
 
         $limit = 1;
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($limit: Int) {
             users(limit: $limit) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'limit' => $limit,
         ])->assertJsonCount($limit, 'data.users');
         $this->assertSame([
@@ -102,7 +102,7 @@ public function testLimitOnInputField(): void
         // @phpstan-ignore-next-line https://github.com/phpstan/phpstan-phpunit/issues/52
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -114,10 +114,10 @@ public function testLimitOnInputField(): void
         type Query {
             users(filter: UserFilter): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $limit = 1;
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($limit: Int) {
             users(filter: {
                 limit: $limit
@@ -125,7 +125,7 @@ public function testLimitOnInputField(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'limit' => $limit,
         ])->assertJsonCount($limit, 'data.users');
     }
@@ -141,7 +141,7 @@ public function testLimitsRelations(): void
             );
         }
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             tasks(limit: Int @limit): [Task!]! @hasMany
@@ -154,11 +154,11 @@ public function testLimitsRelations(): void
         type Query {
             users: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $limit = 1;
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($limit: Int) {
                 users {
                     id
@@ -167,7 +167,7 @@ public function testLimitsRelations(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'limit' => $limit,
             ])
             ->assertJsonCount($limit, 'data.users.0.tasks')
@@ -186,7 +186,7 @@ public function testLimitsWithCache(): void
             );
         }
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID! @cacheKey
             tasks(limit: Int @limit): [Task!]! @hasMany @cache
@@ -199,10 +199,10 @@ public function testLimitsWithCache(): void
         type Query {
             user: [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     id
@@ -211,7 +211,7 @@ public function testLimitsWithCache(): void
                     }
                 }
             }
-            ');
+            GRAPHQL);
 
         $cache = $this->app->make(CacheRepository::class);
 
@@ -233,7 +233,7 @@ public function testLimitsWithCache(): void
         $this->assertSame(3, $task->id);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     id
@@ -242,7 +242,7 @@ public function testLimitsWithCache(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'user' => [
diff --git a/tests/Integration/Schema/Directives/MorphManyDirectiveTest.php b/tests/Integration/Schema/Directives/MorphManyDirectiveTest.php
index 339d4e71ed..9dc03b7001 100644
--- a/tests/Integration/Schema/Directives/MorphManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/MorphManyDirectiveTest.php
@@ -76,7 +76,7 @@ function (): Image {
 
     public function testQueryMorphManyRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -102,9 +102,9 @@ public function testQueryMorphManyRelationship(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             post(id: {$this->post->id}) {
                 id
@@ -122,7 +122,7 @@ public function testQueryMorphManyRelationship(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'post' => [
                     'id' => $this->post->id,
@@ -149,7 +149,7 @@ public function testQueryMorphManyRelationship(): void
 
     public function testQueryMorphManyPaginator(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -166,9 +166,9 @@ public function testQueryMorphManyPaginator(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             post(id: {$this->post->id}) {
                 id
@@ -185,7 +185,7 @@ public function testQueryMorphManyPaginator(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'post' => [
                     'id' => $this->post->id,
@@ -207,7 +207,7 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
     {
         config(['lighthouse.pagination.max_count' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -223,9 +223,9 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ "
+        $result = $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             post(id: {$this->post->id}) {
                 id
@@ -237,7 +237,7 @@ public function testPaginatorTypeIsLimitedByMaxCountFromDirective(): void
                 }
             }
         }
-        ");
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(3, 10),
@@ -249,7 +249,7 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
     {
         config(['lighthouse.pagination.max_count' => 2]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -265,9 +265,9 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ "
+        $result = $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             post(id: {$this->post->id}) {
                 id
@@ -279,7 +279,7 @@ public function testPaginatorTypeIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ");
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(2, 10),
@@ -291,7 +291,7 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
     {
         config(['lighthouse.pagination.max_count' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -307,10 +307,10 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ "
+            ->graphQL(/** @lang GraphQL */ <<<GRAPHQL
             {
                 post(id: {$this->post->id}) {
                     id
@@ -322,13 +322,13 @@ public function testPaginatorTypeIsUnlimitedByMaxCountFromDirective(): void
                     }
                 }
             }
-            ")
+            GRAPHQL)
             ->assertGraphQLErrorFree();
     }
 
     public function testHandlesPaginationWithCountZero(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
             title: String!
@@ -344,10 +344,10 @@ public function testHandlesPaginationWithCountZero(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 post(id: $id) {
                     images(first: 0) {
@@ -366,7 +366,7 @@ public function testHandlesPaginationWithCountZero(): void
                     }
                 }
             }
-            ', [
+            GRAPHQL, [
                 'id' => $this->post->id,
             ])
             ->assertExactJson([
@@ -391,7 +391,7 @@ public function testHandlesPaginationWithCountZero(): void
 
     public function testQueryMorphManyPaginatorWithADefaultCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -407,9 +407,9 @@ public function testQueryMorphManyPaginatorWithADefaultCount(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             task(id: {$this->task->id}) {
                 id
@@ -426,7 +426,7 @@ public function testQueryMorphManyPaginatorWithADefaultCount(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => [
                     'id' => $this->task->id,
@@ -445,7 +445,7 @@ public function testQueryMorphManyPaginatorWithADefaultCount(): void
 
     public function testQueryMorphManyRelayConnection(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -461,9 +461,9 @@ public function testQueryMorphManyRelayConnection(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             task(id: {$this->task->id}) {
                 id
@@ -480,7 +480,7 @@ public function testQueryMorphManyRelayConnection(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => [
                     'id' => $this->task->id,
@@ -499,7 +499,7 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
     {
         config(['lighthouse.pagination.max_count' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -515,9 +515,9 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ "
+        $result = $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             task(id: {$this->task->id}) {
                 id
@@ -531,7 +531,7 @@ public function testRelayTypeIsLimitedByMaxCountFromDirective(): void
                 }
             }
         }
-        ");
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(3, 10),
@@ -543,7 +543,7 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
     {
         config(['lighthouse.pagination.max_count' => 2]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -559,9 +559,9 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ "
+        $result = $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             task(id: {$this->task->id}) {
                 id
@@ -575,7 +575,7 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ");
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(2, 10),
@@ -585,7 +585,7 @@ public function testRelayTypeIsLimitedToMaxCountFromConfig(): void
 
     public function testQueryMorphManyRelayConnectionWithADefaultCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -601,9 +601,9 @@ public function testQueryMorphManyRelayConnectionWithADefaultCount(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             task(id: {$this->task->id}) {
                 id
@@ -620,7 +620,7 @@ public function testQueryMorphManyRelayConnectionWithADefaultCount(): void
                 }
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => [
                     'id' => $this->task->id,
diff --git a/tests/Integration/Schema/Directives/MorphOneDirectiveTest.php b/tests/Integration/Schema/Directives/MorphOneDirectiveTest.php
index cf8a5b326b..9a7532afdc 100644
--- a/tests/Integration/Schema/Directives/MorphOneDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/MorphOneDirectiveTest.php
@@ -50,7 +50,7 @@ protected function setUp(): void
 
     public function testResolveMorphOneRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
         }
@@ -66,9 +66,9 @@ public function testResolveMorphOneRelationship(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id) {
                 id
@@ -78,7 +78,7 @@ public function testResolveMorphOneRelationship(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $this->task->id,
         ])->assertJson([
             'data' => [
@@ -95,7 +95,7 @@ public function testResolveMorphOneRelationship(): void
 
     public function testResolveMorphOneWithCustomName(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
         }
@@ -111,9 +111,9 @@ public function testResolveMorphOneWithCustomName(): void
                 id: ID! @eq
             ): Task @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             task(id: $id) {
                 id
@@ -123,7 +123,7 @@ public function testResolveMorphOneWithCustomName(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $this->task->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Schema/Directives/MorphOneFromUnionTest.php b/tests/Integration/Schema/Directives/MorphOneFromUnionTest.php
index 09ac0c383c..5c13cd9980 100644
--- a/tests/Integration/Schema/Directives/MorphOneFromUnionTest.php
+++ b/tests/Integration/Schema/Directives/MorphOneFromUnionTest.php
@@ -46,7 +46,7 @@ public function testResolveMorphOneRelationshipOnInterface(): void
         $employee->colors()->save($employeeColor);
         $contractor->colors()->save($contractorColor);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         interface Person {
             id: ID!
             user: User! @morphOne
@@ -81,9 +81,9 @@ interface Person {
         type Query {
             colors: [Color!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             colors {
                 id
@@ -101,7 +101,7 @@ interface Person {
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'colors' => [
                     [
diff --git a/tests/Integration/Schema/Directives/MorphToDirectiveTest.php b/tests/Integration/Schema/Directives/MorphToDirectiveTest.php
index d71feb7ca4..6f53d74b2f 100644
--- a/tests/Integration/Schema/Directives/MorphToDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/MorphToDirectiveTest.php
@@ -25,7 +25,7 @@ public function testResolveMorphToRelationship(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             imageable: Task! @morphTo
@@ -41,9 +41,9 @@ public function testResolveMorphToRelationship(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             image(id: $id) {
                 id
@@ -53,7 +53,7 @@ public function testResolveMorphToRelationship(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $image->id,
         ])->assertJson([
             'data' => [
@@ -83,7 +83,7 @@ public function testResolveMorphToWithCustomName(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             customImageable: Task! @morphTo(relation: "imageable")
@@ -99,9 +99,9 @@ public function testResolveMorphToWithCustomName(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             image(id: $id) {
                 id
@@ -111,7 +111,7 @@ public function testResolveMorphToWithCustomName(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $image->id,
         ])->assertJson([
             'data' => [
@@ -151,7 +151,7 @@ public function testResolveMorphToUsingInterfaces(): void
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         interface Imageable {
             id: ID!
         }
@@ -176,9 +176,9 @@ interface Imageable {
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($taskImage: ID!, $postImage: ID!) {
             taskImage: image(id: $taskImage) {
                 id
@@ -207,7 +207,7 @@ interface Imageable {
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'taskImage' => $image->id,
             'postImage' => $postImage->id,
         ])->assertJson([
@@ -257,7 +257,7 @@ public function testResolveMorphToUsingInterfacesWithShortcutForeignKeySelection
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         interface Imageable {
             id: ID!
         }
@@ -282,10 +282,10 @@ interface Imageable {
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($image, $postImage, $task, $post): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($taskImage: ID!, $postImage: ID!) {
                     taskImage: image(id: $taskImage) {
                         id
@@ -310,7 +310,7 @@ interface Imageable {
                         }
                     }
                 }
-            ', [
+            GRAPHQL, [
                 'taskImage' => $image->id,
                 'postImage' => $postImage->id,
             ])->assertJson([
@@ -359,7 +359,7 @@ public function testResolveMorphToUsingInterfacesWithShortcutForeignKeySelection
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         interface Imageable {
             id: ID!
         }
@@ -384,10 +384,10 @@ interface Imageable {
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($image, $postImage, $task, $post): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($taskImage: ID!, $postImage: ID!) {
                     taskImage: image(id: $taskImage) {
                         id
@@ -414,7 +414,7 @@ interface Imageable {
                         }
                     }
                 }
-            ', [
+            GRAPHQL, [
                 'taskImage' => $image->id,
                 'postImage' => $postImage->id,
             ])->assertJson([
@@ -463,7 +463,7 @@ public function testResolveMorphToUsingUnions(): void
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         union Imageable = Task | Post
 
         type Task {
@@ -486,9 +486,9 @@ public function testResolveMorphToUsingUnions(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($taskImage: ID!, $postImage: ID!) {
             taskImage: image(id: $taskImage) {
                 id
@@ -519,7 +519,7 @@ public function testResolveMorphToUsingUnions(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'taskImage' => $image->id,
             'postImage' => $postImage->id,
         ])->assertJson([
@@ -571,7 +571,7 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectID(): void
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         union Imageable = Task | Post
 
         type Task {
@@ -594,10 +594,10 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectID(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($image, $postImage, $task, $post): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($taskImage: ID!, $postImage: ID!) {
                     taskImage: image(id: $taskImage) {
                         id
@@ -622,7 +622,7 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectID(): void
                         }
                     }
                 }
-            ', [
+            GRAPHQL, [
                 'taskImage' => $image->id,
                 'postImage' => $postImage->id,
             ])->assertJson([
@@ -671,7 +671,7 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectIDAndTypename():
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         union Imageable = Task | Post
 
         type Task {
@@ -694,10 +694,10 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectIDAndTypename():
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($image, $postImage, $task, $post): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($taskImage: ID!, $postImage: ID!) {
                     taskImage: image(id: $taskImage) {
                         id
@@ -724,7 +724,7 @@ public function testShortcutsForeignKeySelectionUsingUnionSelectIDAndTypename():
                         }
                     }
                 }
-            ', [
+            GRAPHQL, [
                 'taskImage' => $image->id,
                 'postImage' => $postImage->id,
             ])->assertJson([
@@ -775,7 +775,7 @@ public function testDoesNotShortcutForeignKeySelectionUsingUnionSelectIDAndTypen
         $postImage->imageable()->associate($post);
         $postImage->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         union Imageable = Task | Post
 
         type Task {
@@ -798,10 +798,10 @@ public function testDoesNotShortcutForeignKeySelectionUsingUnionSelectIDAndTypen
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(4, function () use ($image, $postImage, $task, $post): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($taskImage: ID!, $postImage: ID!) {
                     taskImage: image(id: $taskImage) {
                         id
@@ -830,7 +830,7 @@ public function testDoesNotShortcutForeignKeySelectionUsingUnionSelectIDAndTypen
                         }
                     }
                 }
-            ', [
+            GRAPHQL, [
                 'taskImage' => $image->id,
                 'postImage' => $postImage->id,
             ])->assertJson([
@@ -871,7 +871,7 @@ public function testShortcutsForeignKeySelectID(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             imageable: Task! @morphTo
@@ -887,10 +887,10 @@ public function testShortcutsForeignKeySelectID(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($image, $task): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($id: ID!) {
                     image(id: $id) {
                         id
@@ -899,7 +899,7 @@ public function testShortcutsForeignKeySelectID(): void
                         }
                     }
                 }
-                ',
+            GRAPHQL,
                 [
                     'id' => $image->id,
                 ],
@@ -933,7 +933,7 @@ public function testShortcutsForeignKeySelectTypename(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             imageable: Task! @morphTo
@@ -949,10 +949,10 @@ public function testShortcutsForeignKeySelectTypename(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($image): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($id: ID!) {
                     image(id: $id) {
                         id
@@ -961,7 +961,7 @@ public function testShortcutsForeignKeySelectTypename(): void
                         }
                     }
                 }
-                ',
+            GRAPHQL,
                 [
                     'id' => $image->id,
                 ],
@@ -995,7 +995,7 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             imageable: Task! @morphTo
@@ -1011,10 +1011,10 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(1, function () use ($image, $task): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($id: ID!) {
                     image(id: $id) {
                         id
@@ -1024,7 +1024,7 @@ public function testShortcutsForeignKeySelectIDAndTypename(): void
                         }
                     }
                 }
-                ',
+            GRAPHQL,
                 [
                     'id' => $image->id,
                 ],
@@ -1059,7 +1059,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
         $image->imageable()->associate($task);
         $image->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Image {
             id: ID!
             imageable: Task! @morphTo
@@ -1075,10 +1075,10 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
                 id: ID! @eq
             ): Image @find
         }
-        ';
+        GRAPHQL;
 
         $this->assertQueryCountMatches(2, function () use ($image, $task): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
                 query ($id: ID!) {
                     image(id: $id) {
                         id
@@ -1088,7 +1088,7 @@ public function testDoesNotShortcutForeignKeyIfQueryHasFieldSelection(): void
                         }
                     }
                 }
-                ',
+            GRAPHQL,
                 [
                     'id' => $image->id,
                 ],
diff --git a/tests/Integration/Schema/Directives/MorphToManyDirectiveTest.php b/tests/Integration/Schema/Directives/MorphToManyDirectiveTest.php
index c8315e1452..9ed384dd1e 100644
--- a/tests/Integration/Schema/Directives/MorphToManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/MorphToManyDirectiveTest.php
@@ -34,7 +34,7 @@ protected function setUp(): void
 
     public function testResolveMorphToManyRelationship(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Tag {
             id: ID!
             name: String!
@@ -55,9 +55,9 @@ public function testResolveMorphToManyRelationship(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             post(id: $id) {
                 id
@@ -67,7 +67,7 @@ public function testResolveMorphToManyRelationship(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $this->post->id,
         ])->assertJson([
             'data' => [
@@ -86,7 +86,7 @@ public function testResolveMorphToManyRelationship(): void
 
     public function testResolveMorphToManyRelationshipWithRelayConnection(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Tag {
             id: ID!
             name: String!
@@ -102,9 +102,9 @@ public function testResolveMorphToManyRelationshipWithRelayConnection(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             post(id: $id) {
                 id
@@ -120,7 +120,7 @@ public function testResolveMorphToManyRelationshipWithRelayConnection(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $this->post->id,
         ])->assertJson([
             'data' => [
@@ -143,7 +143,7 @@ public function testResolveMorphToManyRelationshipWithRelayConnection(): void
 
     public function testResolveMorphToManyWithCustomName(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Tag {
             id: ID!
             name: String!
@@ -164,9 +164,9 @@ public function testResolveMorphToManyWithCustomName(): void
                 id: ID! @eq
             ): Post @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             post(id: $id) {
                 id
@@ -176,7 +176,7 @@ public function testResolveMorphToManyWithCustomName(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $this->post->id,
         ])->assertJson([
             'data' => [
@@ -264,7 +264,7 @@ interface Tag @interface(resolveType: "{$this->qualifyTestResolver('resolveType'
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($userId: ID!) {
             user (id: $userId) {
                 id
@@ -298,7 +298,7 @@ interface Tag @interface(resolveType: "{$this->qualifyTestResolver('resolveType'
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'userId' => $user->id,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Schema/Directives/NamespacedDirectiveTest.php b/tests/Integration/Schema/Directives/NamespacedDirectiveTest.php
index 904beddb34..b865b3ed15 100644
--- a/tests/Integration/Schema/Directives/NamespacedDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/NamespacedDirectiveTest.php
@@ -8,7 +8,7 @@ final class NamespacedDirectiveTest extends DBTestCase
 {
     public function testCRUDModelDirectives(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: UserQueries! @namespaced
         }
@@ -32,10 +32,10 @@ public function testCRUDModelDirectives(): void
             id: ID!
             name: String!
         }
-        ';
+        GRAPHQL;
 
         $name = 'foo';
-        $createUserResponse = $this->graphQL(/** @lang GraphQL */ '
+        $createUserResponse = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($name: String!) {
             user {
                 create(name: $name) {
@@ -44,7 +44,7 @@ public function testCRUDModelDirectives(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'name' => $name,
         ]);
         $createUserResponse->assertJson([
@@ -58,7 +58,7 @@ public function testCRUDModelDirectives(): void
         ]);
         $userID = $createUserResponse->json('data.user.create.id');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             user {
                 find(id: $id) {
@@ -69,7 +69,7 @@ public function testCRUDModelDirectives(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $userID,
         ])->assertExactJson([
             'data' => [
@@ -87,7 +87,7 @@ public function testCRUDModelDirectives(): void
         ]);
 
         $newName = 'bar';
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!, $name: String) {
             user {
                 update(id: $id, name: $name) {
@@ -96,7 +96,7 @@ public function testCRUDModelDirectives(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $userID,
             'name' => $newName,
         ])->assertExactJson([
@@ -110,7 +110,7 @@ public function testCRUDModelDirectives(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation ($id: ID!) {
             user {
                 delete(id: $id) {
@@ -119,7 +119,7 @@ public function testCRUDModelDirectives(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $userID,
         ])->assertExactJson([
             'data' => [
diff --git a/tests/Integration/Schema/Directives/NestDirectiveTest.php b/tests/Integration/Schema/Directives/NestDirectiveTest.php
index 7d60d42993..34e6313258 100644
--- a/tests/Integration/Schema/Directives/NestDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/NestDirectiveTest.php
@@ -8,7 +8,7 @@ final class NestDirectiveTest extends DBTestCase
 {
     public function testNestDelegates(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             createUser(
                 name: String
@@ -32,9 +32,9 @@ public function testNestDelegates(): void
             name: String
             tasks: [Task!]! @hasMany
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createUser(
                 name: "foo"
@@ -50,7 +50,7 @@ public function testNestDelegates(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'createUser' => [
                     'name' => 'foo',
diff --git a/tests/Integration/Schema/Directives/NotInDirectiveTest.php b/tests/Integration/Schema/Directives/NotInDirectiveTest.php
index 6aee874301..f394ec8910 100644
--- a/tests/Integration/Schema/Directives/NotInDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/NotInDirectiveTest.php
@@ -15,7 +15,7 @@ public function testNotInIDs(): void
         $user2 = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user2);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -23,19 +23,19 @@ public function testNotInIDs(): void
         type Query {
             users(notIDs: [ID!] @notIn(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $user1ID = (string) $user1->id;
         $user2ID = (string) $user2->id;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($notIDs: [ID!]) {
                 users(notIDs: $notIDs) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'notIDs' => [$user1ID],
             ])
             ->assertJson([
@@ -53,7 +53,7 @@ public function testExplicitNull(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -61,16 +61,16 @@ public function testExplicitNull(): void
         type Query {
             users(notIDs: [ID!] @notIn(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($notIDs: [ID!]) {
                 users(notIDs: $notIDs) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'notIDs' => null,
             ])
             ->assertJsonCount($users->count(), 'data.users');
@@ -80,7 +80,7 @@ public function testExplicitNullInArray(): void
     {
         factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -88,16 +88,16 @@ public function testExplicitNullInArray(): void
         type Query {
             users(notIDs: [ID] @notIn(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($notIDs: [ID]) {
                 users(notIDs: $notIDs) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'notIDs' => [null],
             ])
             ->assertJsonCount(0, 'data.users');
@@ -107,7 +107,7 @@ public function testEmptyArray(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -115,16 +115,16 @@ public function testEmptyArray(): void
         type Query {
             users(notIDs: [ID!] @notIn(key: "id")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($notIDs: [ID!]) {
                 users(notIDs: $notIDs) {
                     id
                 }
             }
-            ', [
+            GRAPHQL, [
                 'notIDs' => [],
             ])
             ->assertJsonCount($users->count(), 'data.users');
diff --git a/tests/Integration/Schema/Directives/ScopeDirectiveTest.php b/tests/Integration/Schema/Directives/ScopeDirectiveTest.php
index 95744bad50..17adde0592 100644
--- a/tests/Integration/Schema/Directives/ScopeDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/ScopeDirectiveTest.php
@@ -22,7 +22,7 @@ public function testExplicitName(): void
 
         $taskWithTag->tags()->attach($tag);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks(tags: [String!] @scope(name: "whereTags")): [Task!]! @all
         }
@@ -30,23 +30,23 @@ public function testExplicitName(): void
         type Task {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks {
                 id
             }
         }
-        ')->assertJsonCount(3, 'data.tasks');
+        GRAPHQL)->assertJsonCount(3, 'data.tasks');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($tags: [String!]!) {
             tasks(tags: $tags) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'tags' => [$tag->name],
         ])->assertExactJson([
             'data' => [
@@ -71,7 +71,7 @@ public function testDefaultsScopeToEqualArgumentName(): void
 
         $taskWithTag->tags()->save($tag);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks(whereTags: [String!] @scope): [Task!]! @all
         }
@@ -79,15 +79,15 @@ public function testDefaultsScopeToEqualArgumentName(): void
         type Task {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($whereTags: [String!]!) {
             tasks(whereTags: $whereTags) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'whereTags' => [$tag->name],
         ])->assertExactJson([
             'data' => [
@@ -112,7 +112,7 @@ public function testWorksWithCustomQueryBuilders(): void
         $unnamed->name = null;
         $unnamed->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users(named: Boolean @scope): [User!]! @all
         }
@@ -120,15 +120,15 @@ public function testWorksWithCustomQueryBuilders(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($named: Boolean) {
             users(named: $named) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'named' => true,
         ])->assertExactJson([
             'data' => [
@@ -140,13 +140,13 @@ public function testWorksWithCustomQueryBuilders(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query {
             users {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'named' => false,
         ])->assertSimilarJson([
             'data' => [
@@ -164,7 +164,7 @@ public function testWorksWithCustomQueryBuilders(): void
 
     public function testThrowExceptionOnInvalidScope(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             tasks(
                 name: String @scope(name: "nonExistantScope")
@@ -174,15 +174,15 @@ public function testThrowExceptionOnInvalidScope(): void
         type Task {
             id: ID
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(name: "Lighthouse rocks") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/ThrottleDirectiveTest.php b/tests/Integration/Schema/Directives/ThrottleDirectiveTest.php
index 6c24209714..4b93a266a0 100644
--- a/tests/Integration/Schema/Directives/ThrottleDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/ThrottleDirectiveTest.php
@@ -16,27 +16,27 @@ final class ThrottleDirectiveTest extends TestCase
 {
     public function testWrongLimiterName(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNamedLimiterReturnsRequest(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
         $rateLimiter = $this->app->make(RateLimiter::class);
         $rateLimiter->for(
@@ -45,26 +45,26 @@ public function testNamedLimiterReturnsRequest(): void
         );
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNamedLimiter(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
 
         $rateLimiter = $this->app->make(RateLimiter::class);
         $rateLimiter->for(
@@ -85,17 +85,17 @@ public function testNamedLimiter(): void
 
     public function testLimitClears(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
 
         $rateLimiter = $this->app->make(RateLimiter::class);
         $rateLimiter->for(
@@ -128,17 +128,17 @@ public function testLimitClears(): void
 
     public function testInlineLimiter(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(maxAttempts: 1)
         }
-        ';
+        GRAPHQL;
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
 
         $faker = Factory::create()->unique();
         $ip = $faker->ipv4;
diff --git a/tests/Integration/Schema/Directives/TrimDirectiveTest.php b/tests/Integration/Schema/Directives/TrimDirectiveTest.php
index 61493aef7b..76a92ae2a8 100644
--- a/tests/Integration/Schema/Directives/TrimDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/TrimDirectiveTest.php
@@ -8,19 +8,19 @@ final class TrimDirectiveTest extends TestCase
 {
     public function testTrimsStringArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String! @trim): String! @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): string => $args['bar']);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: "    foo     ")
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => 'foo',
             ],
@@ -29,7 +29,7 @@ public function testTrimsStringArgument(): void
 
     public function testTrimsInputArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         input FooInput {
             bar: String!
         }
@@ -37,17 +37,17 @@ public function testTrimsInputArgument(): void
         type Query {
             foo(input: FooInput! @trim @spread): String! @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): string => $args['bar']);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 bar: "    foo     "
             })
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => 'foo',
             ],
@@ -58,7 +58,7 @@ public function testTrimsAllFieldInputs(): void
     {
         $this->mockResolver(static fn ($_, array $args): array => $args);
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             foo: String!
             bar: [String!]!
@@ -74,9 +74,9 @@ public function testTrimsAllFieldInputs(): void
         type Query {
             foo(input: FooInput! @spread): Foo! @trim @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 foo: " foo "
@@ -88,7 +88,7 @@ public function testTrimsAllFieldInputs(): void
                 baz
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'foo' => 'foo',
diff --git a/tests/Integration/Schema/Directives/UpdateDirectiveTest.php b/tests/Integration/Schema/Directives/UpdateDirectiveTest.php
index c1334e52af..6ef61bf91e 100644
--- a/tests/Integration/Schema/Directives/UpdateDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/UpdateDirectiveTest.php
@@ -19,7 +19,7 @@ public function testUpdateFromFieldArguments(): void
         $company->name = 'foo';
         $company->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -31,9 +31,9 @@ public function testUpdateFromFieldArguments(): void
                 name: String
             ): Company @update
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompany(
                 id: 1
@@ -43,7 +43,7 @@ public function testUpdateFromFieldArguments(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCompany' => [
                     'id' => '1',
@@ -62,7 +62,7 @@ public function testUpdateFromInputObject(): void
         $company->name = 'foo';
         $company->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -78,9 +78,9 @@ public function testUpdateFromInputObject(): void
             id: ID!
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompany(input: {
                 id: 1
@@ -90,7 +90,7 @@ public function testUpdateFromInputObject(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCompany' => [
                     'id' => '1',
@@ -104,7 +104,7 @@ public function testUpdateFromInputObject(): void
 
     public function testThrowsWhenMissingPrimaryKey(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
         }
@@ -112,15 +112,15 @@ public function testThrowsWhenMissingPrimaryKey(): void
         type Mutation {
             updateCompany: Company @update
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompany {
                 id
             }
         }
-        ')->assertGraphQLErrorMessage(UpdateModel::MISSING_PRIMARY_KEY_FOR_UPDATE);
+        GRAPHQL)->assertGraphQLErrorMessage(UpdateModel::MISSING_PRIMARY_KEY_FOR_UPDATE);
     }
 
     public function testUpdateWithCustomPrimaryKey(): void
@@ -130,7 +130,7 @@ public function testUpdateWithCustomPrimaryKey(): void
         $category->name = 'foo';
         $category->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Category {
             category_id: ID!
             name: String!
@@ -142,9 +142,9 @@ public function testUpdateWithCustomPrimaryKey(): void
                 name: String
             ): Category @update
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCategory(
                 category_id: 1
@@ -154,7 +154,7 @@ public function testUpdateWithCustomPrimaryKey(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCategory' => [
                     'category_id' => '1',
@@ -173,7 +173,7 @@ public function testUpdateWithCustomPrimaryKeyAsId(): void
         $category->name = 'foo';
         $category->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Category {
             id: ID! @rename(attribute: "category_id")
             name: String!
@@ -185,9 +185,9 @@ public function testUpdateWithCustomPrimaryKeyAsId(): void
                 name: String
             ): Category @update
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCategory(
                 id: 1
@@ -197,7 +197,7 @@ public function testUpdateWithCustomPrimaryKeyAsId(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCategory' => [
                     'id' => '1',
@@ -216,7 +216,7 @@ public function testDoesNotUpdateWithFailingRelationship(): void
         $user->name = 'Original';
         $user->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String!
@@ -245,10 +245,10 @@ public function testDoesNotUpdateWithFailingRelationship(): void
         input CreateTaskInput {
             thisFieldDoesNotExist: String
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(QueryException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -267,7 +267,7 @@ public function testDoesNotUpdateWithFailingRelationship(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame('Original', User::firstOrFail()->name);
     }
@@ -282,7 +282,7 @@ public function testNestedArgResolver(): void
         $task->id = 3;
         $task->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -307,9 +307,9 @@ public function testNestedArgResolver(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -326,7 +326,7 @@ public function testNestedArgResolver(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -356,7 +356,7 @@ public function testNestedUpdateOnInputList(): void
         $taskB->id = 4;
         $taskB->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -381,9 +381,9 @@ public function testNestedUpdateOnInputList(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -406,7 +406,7 @@ public function testNestedUpdateOnInputList(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
diff --git a/tests/Integration/Schema/Directives/UpdateManyDirectiveTest.php b/tests/Integration/Schema/Directives/UpdateManyDirectiveTest.php
index 8d6811c719..2b284cede9 100644
--- a/tests/Integration/Schema/Directives/UpdateManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/UpdateManyDirectiveTest.php
@@ -22,7 +22,7 @@ public function testUpdateFromFieldArguments(): void
         $company2->name = 'unchanged';
         $company2->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -36,9 +36,9 @@ public function testUpdateFromFieldArguments(): void
         type Mutation {
             updateCompanies(inputs: [UpdateCompanyInput!]!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(inputs: [
                 {
@@ -54,7 +54,7 @@ public function testUpdateFromFieldArguments(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCompanies' => [
                     [
@@ -72,7 +72,7 @@ public function testUpdateFromFieldArguments(): void
 
     public function testEmptyInputs(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -86,16 +86,16 @@ public function testEmptyInputs(): void
         type Mutation {
             updateCompanies(inputs: [UpdateCompanyInput!]!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(inputs: []) {
                 id
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCompanies' => [],
             ],
@@ -111,7 +111,7 @@ public function testRollsBackAllChangesOnPartialFailure(): void
         $company1->name = $name;
         $company1->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -125,11 +125,11 @@ public function testRollsBackAllChangesOnPartialFailure(): void
         type Mutation {
             updateCompanies(inputs: [UpdateCompanyInput]!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
         $exception = null;
         try {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation {
                 updateCompanies(inputs: [
                     {
@@ -145,7 +145,7 @@ public function testRollsBackAllChangesOnPartialFailure(): void
                     name
                 }
             }
-            ');
+            GRAPHQL);
         } catch (ModelNotFoundException $modelNotFoundException) {
             $exception = $modelNotFoundException;
         }
@@ -163,7 +163,7 @@ public function testSameIDMultipleTimes(): void
         $company1->name = 'foo1';
         $company1->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -177,9 +177,9 @@ public function testSameIDMultipleTimes(): void
         type Mutation {
             updateCompanies(inputs: [UpdateCompanyInput]!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(inputs: [
                 {
@@ -195,7 +195,7 @@ public function testSameIDMultipleTimes(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateCompanies' => [
                     [
@@ -213,7 +213,7 @@ public function testSameIDMultipleTimes(): void
 
     public function testMissingArgument(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -227,24 +227,24 @@ public function testMissingArgument(): void
         type Mutation {
             updateCompanies(inputs: [UpdateCompanyInput!]): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             ManyModelMutationDirective::NOT_EXACTLY_ONE_ARGUMENT,
         ));
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies {
                 id
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testMultipleArguments(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -253,24 +253,24 @@ public function testMultipleArguments(): void
         type Mutation {
             updateCompanies(foo: String, bar: String): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             ManyModelMutationDirective::NOT_EXACTLY_ONE_ARGUMENT,
         ));
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(foo: "asf", bar: null) {
                 id
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNotList(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -284,12 +284,12 @@ public function testNotList(): void
         type Mutation {
             updateCompanies(inputs: UpdateCompanyInput!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             ManyModelMutationDirective::ARGUMENT_NOT_LIST,
         ));
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(inputs: {
                 id: 1
@@ -299,12 +299,12 @@ public function testNotList(): void
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNotInputObjects(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Company {
             id: ID!
             name: String!
@@ -313,18 +313,18 @@ public function testNotInputObjects(): void
         type Mutation {
             updateCompanies(inputs: [String!]!): [Company!]! @updateMany
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(
             ManyModelMutationDirective::LIST_ITEM_NOT_INPUT_OBJECT,
         ));
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateCompanies(inputs: ["foo"]) {
                 id
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/UpsertDirectiveTest.php b/tests/Integration/Schema/Directives/UpsertDirectiveTest.php
index fa8460a6e8..a46693ed90 100644
--- a/tests/Integration/Schema/Directives/UpsertDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/UpsertDirectiveTest.php
@@ -21,7 +21,7 @@ public function testNestedArgResolver(): void
         $task->name = 'old';
         $task->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -46,9 +46,9 @@ public function testNestedArgResolver(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -71,7 +71,7 @@ public function testNestedArgResolver(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -94,7 +94,7 @@ public function testNestedInsertOnInputList(): void
     {
         factory(User::class)->create();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -119,9 +119,9 @@ public function testNestedInsertOnInputList(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -140,7 +140,8 @@ public function testNestedInsertOnInputList(): void
                     name
                 }
             }
-        }')->assertJson([
+        }
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -180,7 +181,7 @@ interface IUser
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUser(input: {
                 name: "foo"
@@ -191,7 +192,7 @@ interface IUser
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUser' => [
                     'id' => 1,
diff --git a/tests/Integration/Schema/Directives/UpsertManyDirectiveTest.php b/tests/Integration/Schema/Directives/UpsertManyDirectiveTest.php
index 39b9009675..0aa8380d3b 100644
--- a/tests/Integration/Schema/Directives/UpsertManyDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/UpsertManyDirectiveTest.php
@@ -21,7 +21,7 @@ public function testNestedArgResolver(): void
         $task->name = 'old';
         $task->save();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -46,9 +46,9 @@ public function testNestedArgResolver(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -71,7 +71,7 @@ public function testNestedArgResolver(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -94,7 +94,7 @@ public function testNestedInsertOnInputList(): void
     {
         factory(User::class)->create();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             updateUser(input: UpdateUserInput! @spread): User @update
         }
@@ -119,9 +119,9 @@ public function testNestedInsertOnInputList(): void
             id: Int
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             updateUser(input: {
                 id: 1
@@ -140,7 +140,8 @@ public function testNestedInsertOnInputList(): void
                     name
                 }
             }
-        }')->assertJson([
+        }
+        GRAPHQL)->assertJson([
             'data' => [
                 'updateUser' => [
                     'name' => 'foo',
@@ -180,7 +181,7 @@ interface IUser
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             upsertUsers(inputs: [
                 {
@@ -196,7 +197,7 @@ interface IUser
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'upsertUsers' => [
                     [
diff --git a/tests/Integration/Schema/Directives/WhereBetweenDirectiveTest.php b/tests/Integration/Schema/Directives/WhereBetweenDirectiveTest.php
index a98abad19a..23f2aa08ed 100644
--- a/tests/Integration/Schema/Directives/WhereBetweenDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WhereBetweenDirectiveTest.php
@@ -25,8 +25,8 @@ public function testBetween(): void
         $user3->created_at = Carbon::createStrict(2024);
         $user3->save();
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar DateTime @scalar(class: "Nuwave\\\Lighthouse\\\Schema\\\Types\\\Scalars\\\DateTime")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar DateTime @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\DateTime")
 
         type User {
             id: ID!
@@ -40,16 +40,16 @@ public function testBetween(): void
             from: DateTime!
             to: DateTime!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(createdBetween: { from: "2022-06-06 00:00:00", to: "2023-06-06 00:00:00" }) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'users' => [
@@ -65,8 +65,8 @@ public function testExplicitNull(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar DateTime @scalar(class: "Nuwave\\\Lighthouse\\\Schema\\\Types\\\Scalars\\\DateTime")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar DateTime @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\DateTime")
 
         type User {
             id: ID!
@@ -80,16 +80,16 @@ public function testExplicitNull(): void
             from: DateTime!
             to: DateTime!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(createdBetween: null) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree()
             ->assertJsonCount($users->count(), 'data.users');
     }
diff --git a/tests/Integration/Schema/Directives/WhereDirectiveTest.php b/tests/Integration/Schema/Directives/WhereDirectiveTest.php
index b6d966feb7..7987e37847 100644
--- a/tests/Integration/Schema/Directives/WhereDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WhereDirectiveTest.php
@@ -19,7 +19,7 @@ public function testAttachWhereFilterFromField(): void
         $bar->name = 'bar';
         $bar->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -27,16 +27,16 @@ public function testAttachWhereFilterFromField(): void
         type Query {
             usersBeginningWithF: [User!]! @all @where(key: "name", operator: "like", value: "f%")
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 usersBeginningWithF {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(1, 'data.usersBeginningWithF');
     }
 
@@ -50,8 +50,8 @@ public function testIgnoreNull(): void
         $userWithEmail = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $userWithEmail);
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar DateTime @scalar(class: "Nuwave\\\Lighthouse\\\Schema\\\Types\\\Scalars\\\DateTime")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar DateTime @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\DateTime")
 
         type User {
             id: ID!
@@ -62,10 +62,10 @@ public function testIgnoreNull(): void
             usersIgnoreNull(email: String @where(ignoreNull: true)): [User!]! @all
             usersExplicitNull(email: String @where): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 usersIgnoreNull(email: null) {
                     id
@@ -75,7 +75,7 @@ public function testIgnoreNull(): void
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree()
             ->assertJsonCount(2, 'data.usersIgnoreNull')
             ->assertJsonPath('data.usersIgnoreNull', [
diff --git a/tests/Integration/Schema/Directives/WhereJsonContainsDirectiveDBTest.php b/tests/Integration/Schema/Directives/WhereJsonContainsDirectiveDBTest.php
index aa7bec308a..bd19f00a9d 100644
--- a/tests/Integration/Schema/Directives/WhereJsonContainsDirectiveDBTest.php
+++ b/tests/Integration/Schema/Directives/WhereJsonContainsDirectiveDBTest.php
@@ -7,7 +7,7 @@
 
 final class WhereJsonContainsDirectiveDBTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         users(foo: String! @whereJsonContains(key: "name->nested")): [User!]! @all
     }
@@ -15,7 +15,7 @@ final class WhereJsonContainsDirectiveDBTest extends DBTestCase
     type User {
         name: String
     }
-    ';
+    GRAPHQL;
 
     public function testApplyWhereJsonContainsFilter(): void
     {
@@ -34,13 +34,13 @@ public function testApplyWhereJsonContainsFilter(): void
         ]);
         $userWithBaz->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(foo: "bar") {
                 name
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
diff --git a/tests/Integration/Schema/Directives/WhereNotBetweenDirectiveTest.php b/tests/Integration/Schema/Directives/WhereNotBetweenDirectiveTest.php
index b2cc62cf19..fa70cef5c9 100644
--- a/tests/Integration/Schema/Directives/WhereNotBetweenDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WhereNotBetweenDirectiveTest.php
@@ -11,8 +11,8 @@ public function testExplicitNull(): void
     {
         $users = factory(User::class, 2)->create();
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar DateTime @scalar(class: "Nuwave\\\Lighthouse\\\Schema\\\Types\\\Scalars\\\DateTime")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar DateTime @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\DateTime")
 
         type User {
             id: ID!
@@ -27,16 +27,16 @@ public function testExplicitNull(): void
             from: DateTime!
             to: DateTime!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(notCreatedBetween: null) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorFree()
             ->assertJsonCount($users->count(), 'data.users');
     }
diff --git a/tests/Integration/Schema/Directives/WhereNotNullDirectiveTest.php b/tests/Integration/Schema/Directives/WhereNotNullDirectiveTest.php
index 3db2a3c54c..28dddff1f8 100644
--- a/tests/Integration/Schema/Directives/WhereNotNullDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WhereNotNullDirectiveTest.php
@@ -19,7 +19,7 @@ public function testWhereNull(): void
         $null->name = null;
         $null->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -27,16 +27,16 @@ public function testWhereNull(): void
         type Query {
             users(nameIsNotNull: Boolean @whereNotNull(key: "name")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -51,13 +51,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNotNull: null) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -72,13 +72,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNotNull: true) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -90,13 +90,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNotNull: false) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
diff --git a/tests/Integration/Schema/Directives/WhereNullDirectiveTest.php b/tests/Integration/Schema/Directives/WhereNullDirectiveTest.php
index 825ebb3166..20e14a6a81 100644
--- a/tests/Integration/Schema/Directives/WhereNullDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WhereNullDirectiveTest.php
@@ -19,7 +19,7 @@ public function testWhereNull(): void
         $null->name = null;
         $null->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -27,16 +27,16 @@ public function testWhereNull(): void
         type Query {
             users(nameIsNull: Boolean @whereNull(key: "name")): [User!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -51,13 +51,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNull: null) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -72,13 +72,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNull: true) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
@@ -90,13 +90,13 @@ public function testWhereNull(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(nameIsNull: false) {
                     id
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'users' => [
diff --git a/tests/Integration/Schema/Directives/WithCountDirectiveTest.php b/tests/Integration/Schema/Directives/WithCountDirectiveTest.php
index 04fde40f26..2a861ad740 100644
--- a/tests/Integration/Schema/Directives/WithCountDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WithCountDirectiveTest.php
@@ -11,7 +11,7 @@ final class WithCountDirectiveTest extends DBTestCase
 {
     public function testEagerLoadsRelationCount(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!] @all
         }
@@ -21,7 +21,7 @@ public function testEagerLoadsRelationCount(): void
                 @withCount(relation: "tasks")
                 @method
         }
-        ';
+        GRAPHQL;
 
         factory(User::class, 3)->create()
             ->each(static function (User $user): void {
@@ -33,13 +33,13 @@ public function testEagerLoadsRelationCount(): void
             });
 
         $this->assertQueryCountMatches(2, function (): void {
-            $this->graphQL(/** @lang GraphQL */ '
+            $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     tasksCountLoaded
                 }
             }
-            ')->assertExactJson([
+            GRAPHQL)->assertExactJson([
                 'data' => [
                     'users' => [
                         [
@@ -59,7 +59,7 @@ public function testEagerLoadsRelationCount(): void
 
     public function testFailsToEagerLoadRelationCountWithoutRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!] @all
         }
@@ -67,17 +67,17 @@ public function testFailsToEagerLoadRelationCountWithoutRelation(): void
         type User {
             name: String! @withCount
         }
-        ';
+        GRAPHQL;
 
         factory(User::class)->create();
 
         $this->expectException(DefinitionException::class);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/WithDirectiveTest.php b/tests/Integration/Schema/Directives/WithDirectiveTest.php
index 3e20f752d1..1646f36805 100644
--- a/tests/Integration/Schema/Directives/WithDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WithDirectiveTest.php
@@ -15,7 +15,7 @@ final class WithDirectiveTest extends DBTestCase
 {
     public function testEagerLoadsRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -25,7 +25,7 @@ public function testEagerLoadsRelation(): void
                 @with(relation: "tasks")
                 @method
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -41,13 +41,13 @@ public function testEagerLoadsRelation(): void
             $user->tasksLoaded(),
         );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 tasksLoaded
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'user' => [
                     'tasksLoaded' => true,
@@ -58,7 +58,7 @@ public function testEagerLoadsRelation(): void
 
     public function testEagerLoadsNestedRelation(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: User @first
         }
@@ -68,7 +68,7 @@ public function testEagerLoadsNestedRelation(): void
                 @with(relation: "posts.comments")
                 @method
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -90,13 +90,13 @@ public function testEagerLoadsNestedRelation(): void
             $user->postsCommentsLoaded(),
         );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 postsCommentsLoaded
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'postsCommentsLoaded' => true,
@@ -107,7 +107,7 @@ public function testEagerLoadsNestedRelation(): void
 
     public function testEagerLoadsPolymorphicRelations(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             activity: [Activity!] @all
         }
@@ -132,7 +132,7 @@ public function testEagerLoadsPolymorphicRelations(): void
         type Image {
             id: ID
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -182,7 +182,7 @@ public function testEagerLoadsPolymorphicRelations(): void
                 factory(Image::class, 4)->make(),
             );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             activity {
                 id
@@ -205,7 +205,7 @@ public function testEagerLoadsPolymorphicRelations(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'activity' => [
                     [
@@ -245,7 +245,7 @@ public function testEagerLoadsPolymorphicRelations(): void
 
     public function testEagerLoadsMultipleRelationsAtOnce(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: User
                 @first
@@ -257,7 +257,7 @@ public function testEagerLoadsMultipleRelationsAtOnce(): void
                 @with(relation: "posts.comments")
                 @method
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -285,13 +285,13 @@ public function testEagerLoadsMultipleRelationsAtOnce(): void
             $user->tasksAndPostsCommentsLoaded(),
         );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 tasksAndPostsCommentsLoaded
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'tasksAndPostsCommentsLoaded' => true,
@@ -307,7 +307,7 @@ public function testEagerLoadsMultipleNestedRelationsAtOnce(): void
         $this->markTestSkipped("Not working due to the current naive usage of {$eloquentCollection}::load() in {$simpleModelsLoader}::load().");
 
         // @phpstan-ignore-next-line unreachable due to markTestSkipped
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: User
                 @first
@@ -319,7 +319,7 @@ public function testEagerLoadsMultipleNestedRelationsAtOnce(): void
                 @with(relation: "posts.comments")
                 @method
         }
-        ';
+        GRAPHQL;
 
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
@@ -359,13 +359,13 @@ public function testEagerLoadsMultipleNestedRelationsAtOnce(): void
             $user->postTasksAndPostsCommentsLoaded(),
         );
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 postTasksAndPostsCommentsLoaded
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'postTasksAndPostsCommentsLoaded' => true,
@@ -378,10 +378,10 @@ public function testWithDirectiveOnRootFieldThrows(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @with(relation: "tasks")
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Schema/Directives/WithoutGlobalScopesDirectiveTest.php b/tests/Integration/Schema/Directives/WithoutGlobalScopesDirectiveTest.php
index 985de601fb..ec8a5a736d 100644
--- a/tests/Integration/Schema/Directives/WithoutGlobalScopesDirectiveTest.php
+++ b/tests/Integration/Schema/Directives/WithoutGlobalScopesDirectiveTest.php
@@ -20,7 +20,7 @@ public function testOmitsScopesWhenArgumentValueIsTrue(): void
         $unscheduledPodcast->schedule_at = null;
         $unscheduledPodcast->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             podcasts(
                 includeUnscheduled: Boolean @withoutGlobalScopes(names: ["scheduled"])
@@ -30,22 +30,22 @@ public function testOmitsScopesWhenArgumentValueIsTrue(): void
         type Podcast {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             podcasts {
                 id
             }
         }
-        ')->assertJsonCount(1, 'data.podcasts');
+        GRAPHQL)->assertJsonCount(1, 'data.podcasts');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             podcasts(includeUnscheduled: true) {
                 id
             }
         }
-        ')->assertJsonCount(2, 'data.podcasts');
+        GRAPHQL)->assertJsonCount(2, 'data.podcasts');
     }
 }
diff --git a/tests/Integration/Schema/ResolverProviderTest.php b/tests/Integration/Schema/ResolverProviderTest.php
index 854cb70a97..3595375fbf 100644
--- a/tests/Integration/Schema/ResolverProviderTest.php
+++ b/tests/Integration/Schema/ResolverProviderTest.php
@@ -10,17 +10,17 @@ final class ResolverProviderTest extends TestCase
 {
     public function testRootQuery(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -32,7 +32,7 @@ public function testNonRootFields(): void
         $id = '123';
         $this->mockResolver(['id' => $id]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @mock
         }
@@ -41,16 +41,16 @@ public function testNonRootFields(): void
             id: ID!
             nonRootClassResolver: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 id
                 nonRootClassResolver
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'id' => $id,
@@ -68,7 +68,7 @@ public function testRootQueryMutationPayload(): void
         $barResult = 2;
         $this->mockResolver($barResult, 'bar');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: Int! @mock(key: "bar")
         }
@@ -81,9 +81,9 @@ public function testRootQueryMutationPayload(): void
             result: Int!
             query: Query!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             foo {
                 result
@@ -92,7 +92,7 @@ public function testRootQueryMutationPayload(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'result' => $fooResult,
diff --git a/tests/Integration/Schema/Types/InterfaceTest.php b/tests/Integration/Schema/Types/InterfaceTest.php
index a1ce622131..04d7f50af8 100644
--- a/tests/Integration/Schema/Types/InterfaceTest.php
+++ b/tests/Integration/Schema/Types/InterfaceTest.php
@@ -36,7 +36,7 @@ interface Nameable {
         }
 GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
@@ -45,7 +45,7 @@ interface Nameable {
                 }
             }
         }
-        ')->assertJsonStructure([
+        GRAPHQL)->assertJsonStructure([
             'data' => [
                 'namedThings' => [
                     [
@@ -86,7 +86,7 @@ interface Nameable {
         }
 GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
@@ -95,7 +95,7 @@ interface Nameable {
                 }
             }
         }
-        ')->assertJsonStructure([
+        GRAPHQL)->assertJsonStructure([
             'data' => [
                 'namedThings' => [
                     [
@@ -136,13 +136,13 @@ interface Nameable {
 GRAPHQL;
 
         $this->expectNotToPerformAssertions();
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsOnAmbiguousSchemaMapping(): void
@@ -171,13 +171,13 @@ interface Nameable {
         $this->expectExceptionObject(
             TypeRegistry::unresolvableAbstractTypeMapping(User::class, ['Foo', 'Team']),
         );
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsOnNonOverlappingSchemaMapping(): void
@@ -206,13 +206,13 @@ interface Nameable {
         $this->expectExceptionObject(
             TypeRegistry::unresolvableAbstractTypeMapping(User::class, []),
         );
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testUseCustomTypeResolver(): void
@@ -232,7 +232,7 @@ interface Nameable @interface(resolveType: "{$this->qualifyTestResolver('resolve
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             namedThings {
                 name
@@ -241,7 +241,7 @@ interface Nameable @interface(resolveType: "{$this->qualifyTestResolver('resolve
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'namedThings' => $this->fetchGuy(),
             ],
@@ -272,7 +272,7 @@ interface Nameable {
         }
 GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 types {
@@ -284,7 +284,7 @@ interface Nameable {
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $interface = (new Collection($result->json('data.__schema.types')))
             ->firstWhere('name', 'Nameable');
@@ -317,7 +317,7 @@ interface HasPosts {
         }
         GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             __type(name: "HasPosts") {
                 name
@@ -333,7 +333,7 @@ interface HasPosts {
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame('HasPosts', $result->json('data.__type.name'));
         $this->assertSame('INTERFACE', $result->json('data.__type.kind'));
diff --git a/tests/Integration/Schema/Types/LaravelEnumTypeDBTest.php b/tests/Integration/Schema/Types/LaravelEnumTypeDBTest.php
index 8f93f24944..004d5a1d26 100644
--- a/tests/Integration/Schema/Types/LaravelEnumTypeDBTest.php
+++ b/tests/Integration/Schema/Types/LaravelEnumTypeDBTest.php
@@ -21,7 +21,7 @@ protected function setUp(): void
 
     public function testUseLaravelEnumType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             withEnum(type: AOrB @eq): WithEnum @find
         }
@@ -33,7 +33,7 @@ public function testUseLaravelEnumType(): void
         type WithEnum {
             type: AOrB
         }
-        ';
+        GRAPHQL;
 
         $this->typeRegistry->register(
             new LaravelEnumType(AOrB::class),
@@ -43,27 +43,27 @@ public function testUseLaravelEnumType(): void
             'type' => 'A',
         ];
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             createWithEnum(type: A) {
                 type
             }
         }
-        ')->assertJsonFragment($typeA);
+        GRAPHQL)->assertJsonFragment($typeA);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             withEnum(type: A) {
                 type
             }
         }
-        ')->assertJsonFragment($typeA);
+        GRAPHQL)->assertJsonFragment($typeA);
     }
 
     public function testWhereJsonContainsUsingEnumType(): void
     {
         // We use the "name" field to store the "type" JSON
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             withEnum(
                 type: AOrB @whereJsonContains(key: "name")
@@ -73,7 +73,7 @@ public function testWhereJsonContainsUsingEnumType(): void
         type WithEnum {
             name: String
         }
-        ';
+        GRAPHQL;
 
         $this->typeRegistry->register(
             new LaravelEnumType(AOrB::class),
@@ -85,13 +85,13 @@ public function testWhereJsonContainsUsingEnumType(): void
         $withEnum->name = $encodedType;
         $withEnum->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             withEnum(type: A) {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'withEnum' => [
                     'name' => $encodedType,
@@ -102,7 +102,7 @@ public function testWhereJsonContainsUsingEnumType(): void
 
     public function testScopeUsingEnumType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             withEnum(
                 byType: AOrB @scope
@@ -112,7 +112,7 @@ public function testScopeUsingEnumType(): void
         type WithEnum {
             type: AOrB
         }
-        ';
+        GRAPHQL;
 
         $this->typeRegistry->register(
             new LaravelEnumType(AOrB::class),
@@ -124,13 +124,13 @@ public function testScopeUsingEnumType(): void
         $withEnum->type = $a;
         $withEnum->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($type: AOrB) {
             withEnum(byType: $type) {
                 type
             }
         }
-        ', [
+        GRAPHQL, [
             'type' => $a->key,
         ])->assertJson([
             'data' => [
diff --git a/tests/Integration/Schema/Types/UnionTest.php b/tests/Integration/Schema/Types/UnionTest.php
index 82cbee0314..cabdcb1082 100644
--- a/tests/Integration/Schema/Types/UnionTest.php
+++ b/tests/Integration/Schema/Types/UnionTest.php
@@ -62,18 +62,18 @@ public function testConsidersRenamedModels(): void
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
-        {
-            stuff {
-                ... on Foo {
-                    name
-                }
-                ... on Post {
-                    title
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                {
+                    stuff {
+                        ... on Foo {
+                            name
+                        }
+                        ... on Post {
+                            title
+                        }
+                    }
                 }
-            }
-        }
-        ')->assertJsonStructure([
+        GRAPHQL)->assertJsonStructure([
             'data' => [
                 'stuff' => [
                     [
@@ -91,8 +91,7 @@ public function testRejectsUnionWithString(): void
     {
         $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<GRAPHQL
         union Stuff = String
-
-GRAPHQL
+GRAPHQL . "\n",
         );
 
         $this->expectExceptionObject(new InvariantViolation(
@@ -128,18 +127,18 @@ public function testThrowsOnAmbiguousSchemaMapping(): void
         $this->expectExceptionObject(
             TypeRegistry::unresolvableAbstractTypeMapping(User::class, ['Foo', 'Post']),
         );
-        $this->graphQL(/** @lang GraphQL */ '
-        {
-            stuff {
-                ... on Foo {
-                    name
-                }
-                ... on Post {
-                    title
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                {
+                    stuff {
+                        ... on Foo {
+                            name
+                        }
+                        ... on Post {
+                            title
+                        }
+                    }
                 }
-            }
-        }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsOnNonOverlappingSchemaMapping(): void
@@ -169,15 +168,15 @@ public function testThrowsOnNonOverlappingSchemaMapping(): void
         $this->expectExceptionObject(
             TypeRegistry::unresolvableAbstractTypeMapping(User::class, []),
         );
-        $this->graphQL(/** @lang GraphQL */ '
-        {
-            stuff {
-                ... on Post {
-                    title
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                {
+                    stuff {
+                        ... on Post {
+                            title
+                        }
+                    }
                 }
-            }
-        }
-        ');
+        GRAPHQL);
     }
 
     /** @return \Illuminate\Support\Collection<int, \Tests\Utils\Models\User|\Tests\Utils\Models\Post> */
@@ -206,13 +205,15 @@ public static function schemaAndQuery(bool $withCustomTypeResolver): array
             : '';
 
         $customResolver = $withCustomTypeResolver
-            ? /** @lang GraphQL */ '@union(resolveType: "Tests\\\\Utils\\\\Unions\\\\CustomStuff@resolveType")'
+            ? /** @lang GraphQL */ <<<'GRAPHQL'
+            @union(resolveType: "Tests\\Utils\\Unions\\CustomStuff@resolveType")
+            GRAPHQL
             : '';
 
         $fetchResultsResolver = self::qualifyTestResolver('fetchResults');
 
         return [
-/** @lang GraphQL */ "
+/** @lang GraphQL */ <<<GRAPHQL
             union Stuff {$customResolver} = {$prefix}User | {$prefix}Post
 
             type {$prefix}User {
@@ -224,10 +225,10 @@ public static function schemaAndQuery(bool $withCustomTypeResolver): array
             }
 
             type Query {
-                stuff: [Stuff!]! @field(resolver: \"{$fetchResultsResolver}\")
+                stuff: [Stuff!]! @field(resolver: "{$fetchResultsResolver}")
             }
-            ",
-/** @lang GraphQL */ "
+GRAPHQL,
+/** @lang GraphQL */ <<<GRAPHQL
             {
                 stuff {
                     ... on {$prefix}User {
@@ -238,7 +239,7 @@ public static function schemaAndQuery(bool $withCustomTypeResolver): array
                     }
                 }
             }
-            ",
+GRAPHQL,
         ];
     }
 }
diff --git a/tests/Integration/Schema/ValidatorTest.php b/tests/Integration/Schema/ValidatorTest.php
index c75969b25b..cc0d28d241 100644
--- a/tests/Integration/Schema/ValidatorTest.php
+++ b/tests/Integration/Schema/ValidatorTest.php
@@ -10,7 +10,7 @@ final class ValidatorTest extends TestCase
 {
     public function testOutputTypeUsedAsInput(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(foo: Foo): Int
         }
@@ -18,7 +18,7 @@ public function testOutputTypeUsedAsInput(): void
         type Foo {
             foo: Int
         }
-        ';
+        GRAPHQL;
 
         $schemaValidator = $this->app->make(SchemaValidator::class);
 
diff --git a/tests/Integration/SchemaCacheTest.php b/tests/Integration/SchemaCacheTest.php
index f4bb85023c..7aa8d01176 100644
--- a/tests/Integration/SchemaCacheTest.php
+++ b/tests/Integration/SchemaCacheTest.php
@@ -32,7 +32,7 @@ protected function tearDown(): void
 
     public function testSchemaCachingWithUnionType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo @mock
         }
@@ -46,14 +46,14 @@ public function testSchemaCachingWithUnionType(): void
         type Color {
             id: ID
         }
-        ';
+        GRAPHQL;
         $this->cacheSchema();
 
         $comment = new Comment();
         $comment->comment = 'foo';
         $this->mockResolver($comment);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 ... on Comment {
@@ -61,7 +61,7 @@ public function testSchemaCachingWithUnionType(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => [
                     'comment' => $comment->comment,
@@ -80,11 +80,11 @@ public function testInvalidSchemaCacheContents(): void
 
         $this->expectException(\AssertionError::class);
         $this->expectExceptionMessage("The schema cache file at {$path} is expected to return an array.");
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     private function cacheSchema(): void
diff --git a/tests/Integration/Scout/SearchDirectiveTest.php b/tests/Integration/Scout/SearchDirectiveTest.php
index 0a17979dde..0e8de177ba 100644
--- a/tests/Integration/Scout/SearchDirectiveTest.php
+++ b/tests/Integration/Scout/SearchDirectiveTest.php
@@ -34,7 +34,7 @@ public function testSearch(): void
                 new EloquentCollection([$postA, $postB]),
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Post {
             id: ID!
             title: String!
@@ -45,16 +45,16 @@ public function testSearch(): void
                 search: String @search
             ): [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(search: "great") {
                 id
                 title
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'posts' => [
                     [
@@ -78,7 +78,7 @@ public function testSearchWithEq(): void
             ->andReturn(new EloquentCollection())
             ->once();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Post {
             id: Int!
         }
@@ -89,15 +89,15 @@ public function testSearchWithEq(): void
                 search: String @search
             ): [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: Int) {
             posts(id: $id, search: "great") {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $id,
         ])->assertJson([
             'data' => [
@@ -133,13 +133,13 @@ public function testSearchWithBuilder(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: Int!) {
             posts(input: { id: $id }, search: "greatness") {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $id,
         ])->assertJson([
             'data' => [
@@ -162,7 +162,7 @@ public function testSearchWithTrashed(): void
             ->andReturn(new EloquentCollection())
             ->once();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: Int!
         }
@@ -173,15 +173,15 @@ public function testSearchWithTrashed(): void
                 search: String @search
             ): [Post!]! @all @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(search: "foo", trashed: ONLY) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'posts' => [],
             ],
@@ -206,25 +206,25 @@ public function testSearchWithinCustomIndex(): void
             )
             ->once();
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Post {
             id: ID!
         }
 
         type Query {
             posts(
-                search: String @search(within: \"{$myIndex}\")
+                search: String @search(within: "{$myIndex}")
             ): [Post!]! @all
         }
-        ";
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(search: "great") {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'posts' => [
                     [
@@ -240,7 +240,7 @@ public function testSearchWithinCustomIndex(): void
 
     public function testWithinMustBeString(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -250,22 +250,22 @@ public function testWithinMustBeString(): void
                 search: String @search(within: 123)
             ): [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(search: "great") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testMultipleSearchesAreNotAllowed(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -276,22 +276,22 @@ public function testMultipleSearchesAreNotAllowed(): void
                 second: String @search
             ): [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(ScoutException::class);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(first: "great", second: "nope") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testIncompatibleArgBuildersAreNotAllowed(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -302,22 +302,22 @@ public function testIncompatibleArgBuildersAreNotAllowed(): void
                 nope: String @neq
             ): [Post!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(ScoutException::class);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(search: "great", nope: "nope") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testModelMustBeSearchable(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -327,17 +327,17 @@ public function testModelMustBeSearchable(): void
                 search: String @search
             ): [Task!]! @all
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(ScoutException::class);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(search: "great") {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testHandlesScoutBuilderPaginationArguments(): void
@@ -363,7 +363,7 @@ public function testHandlesScoutBuilderPaginationArguments(): void
             ->andReturn(new EloquentCollection([$postA, $postB]))
             ->once();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Post {
             id: ID!
         }
@@ -373,9 +373,9 @@ public function testHandlesScoutBuilderPaginationArguments(): void
                 search: String @search
             ): [Post!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(first: 10, search: "great") {
                 data {
@@ -383,7 +383,7 @@ public function testHandlesScoutBuilderPaginationArguments(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'posts' => [
                     'data' => [
diff --git a/tests/Integration/SoftDeletes/ForceDeleteDirectiveTest.php b/tests/Integration/SoftDeletes/ForceDeleteDirectiveTest.php
index c9aadb21b1..b96d3dd728 100644
--- a/tests/Integration/SoftDeletes/ForceDeleteDirectiveTest.php
+++ b/tests/Integration/SoftDeletes/ForceDeleteDirectiveTest.php
@@ -14,7 +14,7 @@ public function testForceDeletesTaskAndReturnsIt(): void
     {
         factory(Task::class)->create();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -22,15 +22,15 @@ public function testForceDeletesTaskAndReturnsIt(): void
         type Mutation {
             forceDeleteTask(id: ID! @whereKey): Task @forceDelete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             forceDeleteTask(id: 1) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'forceDeleteTask' => [
                     'id' => 1,
@@ -46,7 +46,7 @@ public function testForceDeletesDeletedTaskAndReturnsIt(): void
         $task = factory(Task::class)->create();
         $task->delete();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -54,15 +54,15 @@ public function testForceDeletesDeletedTaskAndReturnsIt(): void
         type Mutation {
             forceDeleteTask(id: ID! @whereKey): Task @forceDelete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             forceDeleteTask(id: 1) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'forceDeleteTask' => [
                     'id' => 1,
@@ -77,7 +77,7 @@ public function testForceDeletesMultipleTasksAndReturnsThem(): void
     {
         factory(Task::class, 2)->create();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String
@@ -86,15 +86,15 @@ public function testForceDeletesMultipleTasksAndReturnsThem(): void
         type Mutation {
             forceDeleteTasks(id: [ID!]! @whereKey): [Task!]! @forceDelete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             forceDeleteTasks(id: [1, 2]) {
                 name
             }
         }
-        ')->assertJsonCount(2, 'data.forceDeleteTasks');
+        GRAPHQL)->assertJsonCount(2, 'data.forceDeleteTasks');
 
         $this->assertCount(0, Task::withTrashed()->get());
     }
@@ -110,7 +110,7 @@ public function testDirectiveIncludesTrashedModelsWhenUsingForceDelete(): void
         $user->tasks()->save($task);
         $task->delete();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String
@@ -121,15 +121,15 @@ public function testDirectiveIncludesTrashedModelsWhenUsingForceDelete(): void
                 @can(ability: "delete", query: true)
                 @forceDelete
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             forceDeleteTasks(id: 1) {
                 name
             }
         }
-        ')->assertJsonCount(1, 'data.forceDeleteTasks');
+        GRAPHQL)->assertJsonCount(1, 'data.forceDeleteTasks');
 
         $this->assertCount(0, Task::withTrashed()->get());
     }
@@ -145,7 +145,7 @@ public function testDirectiveUsesExplicitTrashedArgument(): void
         $user->tasks()->save($task);
         $task->delete();
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String
@@ -158,15 +158,15 @@ public function testDirectiveUsesExplicitTrashedArgument(): void
                 # The order has to be like this, otherwise @forceDelete will throw
                 @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             forceDeleteTasks(id: 1, trashed: WITH) {
                 name
             }
         }
-        ')->assertJsonCount(1, 'data.forceDeleteTasks');
+        GRAPHQL)->assertJsonCount(1, 'data.forceDeleteTasks');
 
         $this->assertCount(0, Task::withTrashed()->get());
     }
@@ -174,7 +174,7 @@ public function testDirectiveUsesExplicitTrashedArgument(): void
     public function testRejectsUsingDirectiveWithNonSoftDeleteModels(): void
     {
         $this->expectExceptionMessage(ForceDeleteDirective::MODEL_NOT_USING_SOFT_DELETES);
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -182,6 +182,6 @@ public function testRejectsUsingDirectiveWithNonSoftDeleteModels(): void
         type Query {
             deleteUser(id: ID! @whereKey): User @forceDelete
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/SoftDeletes/RestoreDirectiveTest.php b/tests/Integration/SoftDeletes/RestoreDirectiveTest.php
index 54f9f6dcbd..30f8336c07 100644
--- a/tests/Integration/SoftDeletes/RestoreDirectiveTest.php
+++ b/tests/Integration/SoftDeletes/RestoreDirectiveTest.php
@@ -18,7 +18,7 @@ public function testRestoresTaskAndReturnsIt(): void
         $this->assertCount(1, Task::withTrashed()->get());
         $this->assertCount(0, Task::withoutTrashed()->get());
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -26,15 +26,15 @@ public function testRestoresTaskAndReturnsIt(): void
         type Mutation {
             restoreTask(id: ID! @whereKey): Task @restore
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             restoreTask(id: 1) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'restoreTask' => [
                     'id' => 1,
@@ -55,7 +55,7 @@ public function testRestoresMultipleTasksAndReturnsThem(): void
         $this->assertCount(2, Task::withTrashed()->get());
         $this->assertCount(0, Task::withoutTrashed()->get());
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String
@@ -64,15 +64,15 @@ public function testRestoresMultipleTasksAndReturnsThem(): void
         type Mutation {
             restoreTasks(id: [ID!]! @whereKey): [Task!]! @restore
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             restoreTasks(id: [1, 2]) {
                 name
             }
         }
-        ')->assertJsonCount(2, 'data.restoreTasks');
+        GRAPHQL)->assertJsonCount(2, 'data.restoreTasks');
 
         $this->assertCount(2, Task::withoutTrashed()->get());
     }
@@ -90,7 +90,7 @@ public function testDirectiveExcludesTrashedModelsWhenUsingRestore(): void
 
         $this->assertCount(0, Task::withoutTrashed()->get());
 
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
             name: String
@@ -101,15 +101,15 @@ public function testDirectiveExcludesTrashedModelsWhenUsingRestore(): void
                 @can(ability: "delete", query: true)
                 @restore
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         mutation {
             restoreTasks(id: 1) {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'restoreTasks' => [
                     'name' => $task->name,
@@ -124,7 +124,7 @@ public function testRejectsUsingDirectiveWithNonSoftDeleteModels(): void
     {
         $this->expectExceptionMessage(RestoreDirective::MODEL_NOT_USING_SOFT_DELETES);
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -132,6 +132,6 @@ public function testRejectsUsingDirectiveWithNonSoftDeleteModels(): void
         type Query {
             restoreUser(id: ID! @whereKey): User @restore
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/SoftDeletes/SoftDeletesAndTrashedDirectiveTest.php b/tests/Integration/SoftDeletes/SoftDeletesAndTrashedDirectiveTest.php
index 1a39ad933a..0c36487da7 100644
--- a/tests/Integration/SoftDeletes/SoftDeletesAndTrashedDirectiveTest.php
+++ b/tests/Integration/SoftDeletes/SoftDeletesAndTrashedDirectiveTest.php
@@ -15,7 +15,7 @@ public function testWithAllDirective(): void
         $taskToRemove = $tasks[2];
         $taskToRemove->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -23,15 +23,15 @@ public function testWithAllDirective(): void
         type Query {
             tasks: [Task!]! @all @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(trashed: ONLY) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'tasks' => [
                     [
@@ -41,29 +41,29 @@ public function testWithAllDirective(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(trashed: WITH) {
                 id
             }
         }
-        ')->assertJsonCount(3, 'data.tasks');
+        GRAPHQL)->assertJsonCount(3, 'data.tasks');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(trashed: WITHOUT) {
                 id
             }
         }
-        ')->assertJsonCount(2, 'data.tasks');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks {
                 id
             }
         }
-        ')->assertJsonCount(2, 'data.tasks');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks');
     }
 
     public function testNullDoesNothing(): void
@@ -75,7 +75,7 @@ public function testNullDoesNothing(): void
 
         $leftoverTask = $tasks[1];
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -83,15 +83,15 @@ public function testNullDoesNothing(): void
         type Query {
             tasks: [Task!]! @all @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(trashed: null) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'tasks' => [
                     [
@@ -108,7 +108,7 @@ public function testWithFindDirective(): void
         $taskToRemove = factory(Task::class)->create();
         $taskToRemove->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -116,15 +116,15 @@ public function testWithFindDirective(): void
         type Query {
             task(id: ID! @eq): Task @find @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             task(id: 1, trashed: ONLY) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => [
                     'id' => $taskToRemove->id,
@@ -132,13 +132,13 @@ public function testWithFindDirective(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             task(id: 1, trashed: WITH) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => [
                     'id' => $taskToRemove->id,
@@ -146,25 +146,25 @@ public function testWithFindDirective(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             task(id: 1, trashed: WITHOUT) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => null,
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             task(id: 1) {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'task' => null,
             ],
@@ -178,7 +178,7 @@ public function testWithPaginateDirective(): void
         $taskToRemove = $tasks[2];
         $taskToRemove->delete();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -186,9 +186,9 @@ public function testWithPaginateDirective(): void
         type Query {
             tasks: [Task!]! @paginate @softDeletes
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 10, trashed: ONLY) {
                 data {
@@ -196,7 +196,7 @@ public function testWithPaginateDirective(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'tasks' => [
                     'data' => [
@@ -208,7 +208,7 @@ public function testWithPaginateDirective(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 10, trashed: WITH) {
                 data {
@@ -216,9 +216,9 @@ public function testWithPaginateDirective(): void
                 }
             }
         }
-        ')->assertJsonCount(3, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(3, 'data.tasks.data');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 10, trashed: WITHOUT) {
                 data {
@@ -226,9 +226,9 @@ public function testWithPaginateDirective(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks.data');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             tasks(first: 10) {
                 data {
@@ -236,7 +236,7 @@ public function testWithPaginateDirective(): void
                 }
             }
         }
-        ')->assertJsonCount(2, 'data.tasks.data');
+        GRAPHQL)->assertJsonCount(2, 'data.tasks.data');
     }
 
     public function testNested(): void
@@ -254,7 +254,7 @@ public function testNested(): void
             factory(Task::class, 2)->make(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Task {
             id: ID!
         }
@@ -269,9 +269,9 @@ public function testNested(): void
             usersPaginated: [User!]! @paginate
             user(id: ID! @eq): User @find
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users {
                 tasks(trashed: ONLY) {
@@ -279,7 +279,7 @@ public function testNested(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     [
@@ -293,7 +293,7 @@ public function testNested(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             usersPaginated(first: 10) {
                 data {
@@ -303,7 +303,7 @@ public function testNested(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'usersPaginated' => [
                     'data' => [
@@ -319,7 +319,7 @@ public function testNested(): void
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(id: 1) {
                 tasks(trashed: ONLY) {
@@ -327,7 +327,7 @@ public function testNested(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'tasks' => [
@@ -340,7 +340,7 @@ public function testNested(): void
         ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     tasksWith: tasks(trashed: WITH) {
@@ -354,13 +354,13 @@ public function testNested(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(3, 'data.users.0.tasksWith')
             ->assertJsonCount(2, 'data.users.0.tasksWithout')
             ->assertJsonCount(2, 'data.users.0.tasksSimple');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 usersPaginated(first: 10) {
                     data {
@@ -376,13 +376,13 @@ public function testNested(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(3, 'data.usersPaginated.data.0.tasksWith')
             ->assertJsonCount(2, 'data.usersPaginated.data.0.tasksWithout')
             ->assertJsonCount(2, 'data.usersPaginated.data.0.tasksSimple');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user(id: 1) {
                     tasksWith: tasks(trashed: WITH) {
@@ -396,7 +396,7 @@ public function testNested(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJsonCount(3, 'data.user.tasksWith')
             ->assertJsonCount(2, 'data.user.tasksWithout')
             ->assertJsonCount(2, 'data.user.tasksSimple');
@@ -404,7 +404,7 @@ public function testNested(): void
 
     public function testThrowsIfModelDoesNotSupportSoftDeletesTrashed(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             trashed(trashed: Trashed @trashed): [User!]! @all
         }
@@ -412,21 +412,21 @@ public function testThrowsIfModelDoesNotSupportSoftDeletesTrashed(): void
         type User {
             id: ID
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionMessage(TrashedDirective::MODEL_MUST_USE_SOFT_DELETES);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             trashed(trashed: WITH) {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsIfModelDoesNotSupportSoftDeletes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             softDeletes: [User!]! @all @softDeletes
         }
@@ -434,15 +434,15 @@ public function testThrowsIfModelDoesNotSupportSoftDeletes(): void
         type User {
             id: ID
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionMessage(TrashedDirective::MODEL_MUST_USE_SOFT_DELETES);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             softDeletes(trashed: WITH) {
                 id
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Subscriptions/Broadcast/BroadcastDBTest.php b/tests/Integration/Subscriptions/Broadcast/BroadcastDBTest.php
index d800bf4253..c17b7d91a0 100644
--- a/tests/Integration/Subscriptions/Broadcast/BroadcastDBTest.php
+++ b/tests/Integration/Subscriptions/Broadcast/BroadcastDBTest.php
@@ -53,13 +53,13 @@ public function testBroadcastsFromPhp(): void
             ->shouldReceive('broadcast')
             ->once();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             subscription UserUpdated {
                 taskUpdated {
                     name
                 }
             }
-        ');
+        GRAPHQL);
 
         Subscription::broadcast('taskUpdated', []);
     }
@@ -70,20 +70,20 @@ public function testBroadcastsFromSchema(): void
             ->shouldReceive('broadcast')
             ->once();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             subscription TaskUpdated {
                 taskUpdated {
                     name
                 }
             }
-        ');
+        GRAPHQL);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             mutation {
                 updateTask(id: 1, name: "New name") {
                     name
                 }
             }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Subscriptions/EchoBroadcaster/AuthorizeRequestsTest.php b/tests/Integration/Subscriptions/EchoBroadcaster/AuthorizeRequestsTest.php
index 4a5c0a6b2a..ec89d717d0 100644
--- a/tests/Integration/Subscriptions/EchoBroadcaster/AuthorizeRequestsTest.php
+++ b/tests/Integration/Subscriptions/EchoBroadcaster/AuthorizeRequestsTest.php
@@ -108,13 +108,13 @@ public function testEchoClientAuthorizeFailsAfterDelete(): void
 
     private function querySubscription(): TestResponse
     {
-        return $this->graphQL(/** @lang GraphQL */ '
+        return $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         subscription {
             taskUpdated(id: 123) {
                 id
                 name
             }
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Integration/Subscriptions/Storage/RedisStorageManagerTest.php b/tests/Integration/Subscriptions/Storage/RedisStorageManagerTest.php
index 968fbd41df..26ed1e413d 100644
--- a/tests/Integration/Subscriptions/Storage/RedisStorageManagerTest.php
+++ b/tests/Integration/Subscriptions/Storage/RedisStorageManagerTest.php
@@ -16,15 +16,15 @@ final class RedisStorageManagerTest extends TestCase
     use EnablesSubscriptionServiceProvider;
 
     protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
-    type Task {
-        id: ID!
-        name: String!
-    }
-
-    type Subscription {
-        taskUpdated(id: ID!): Task
-        taskCreated: Task
-    }
+        type Task {
+            id: ID!
+            name: String!
+        }
+    
+        type Subscription {
+            taskUpdated(id: ID!): Task
+            taskCreated: Task
+        }
     GRAPHQL . self::PLACEHOLDER_QUERY;
 
     public function testSubscriptionStoredWithPrefix(): void
@@ -111,7 +111,9 @@ public function testSocketIDStoredOnSubscribe(): void
     }
 
     /** @param  array<string, mixed>  $headers */
-    private function querySubscription(string $topic = /** @lang GraphQL */ 'taskUpdated(id: 123)', array $headers = []): TestResponse
+    private function querySubscription(string $topic = /** @lang GraphQL */ <<<'GRAPHQL'
+    taskUpdated(id: 123)
+    GRAPHQL, array $headers = []): TestResponse
     {
         return $this->graphQL(/** @lang GraphQL */ query: "
         subscription {
diff --git a/tests/Integration/Tracing/ApolloTracingExtensionTest.php b/tests/Integration/Tracing/ApolloTracingExtensionTest.php
index cc3f174998..224ae57065 100644
--- a/tests/Integration/Tracing/ApolloTracingExtensionTest.php
+++ b/tests/Integration/Tracing/ApolloTracingExtensionTest.php
@@ -7,11 +7,11 @@
 
 final class ApolloTracingExtensionTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
-        foo: String! @field(resolver: "Tests\\\Integration\\\Tracing\\\ApolloTracingExtensionTest@resolve")
+        foo: String! @field(resolver: "Tests\\Integration\\Tracing\\ApolloTracingExtensionTest@resolve")
     }
-    ';
+    GRAPHQL;
 
     protected function getPackageProviders($app): array
     {
@@ -24,11 +24,11 @@ protected function getPackageProviders($app): array
     public function testAddTracingExtensionMetaToResult(): void
     {
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo
             }
-            ')
+            GRAPHQL)
             ->assertJsonStructure([
                 'extensions' => [
                     'tracing' => [
@@ -43,11 +43,11 @@ public function testAddTracingExtensionMetaToResult(): void
     public function testAddTracingExtensionMetaToBatchedResults(): void
     {
         $postData = [
-            'query' => /** @lang GraphQL */ '
+            'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 {
                     foo
                 }
-                ',
+            GRAPHQL,
         ];
         $expectedResponse = [
             'extensions' => [
diff --git a/tests/Integration/Tracing/FederatedTracingExtensionTest.php b/tests/Integration/Tracing/FederatedTracingExtensionTest.php
index 51c399f488..71e1057fad 100644
--- a/tests/Integration/Tracing/FederatedTracingExtensionTest.php
+++ b/tests/Integration/Tracing/FederatedTracingExtensionTest.php
@@ -13,16 +13,16 @@
 
 final class FederatedTracingExtensionTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         foo: Foo!
     }
 
     type Foo @key(fields: "id") {
-        id: String! @field(resolver: "Tests\\\Integration\\\Tracing\\\FederatedTracingExtensionTest@resolve")
-        bar: String! @field(resolver: "Tests\\\Integration\\\Tracing\\\FederatedTracingExtensionTest@throw")
+        id: String! @field(resolver: "Tests\\Integration\\Tracing\\FederatedTracingExtensionTest@resolve")
+        bar: String! @field(resolver: "Tests\\Integration\\Tracing\\FederatedTracingExtensionTest@throw")
     }
-    ';
+    GRAPHQL;
 
     protected function getPackageProviders($app): array
     {
@@ -45,11 +45,11 @@ protected function setUp(): void
     public function testHeaderIsRequiredToEnableTracing(): void
     {
         $response = $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo { id }
             }
-            ');
+            GRAPHQL);
 
         $response->assertJsonMissingPath('extensions.ftv1');
     }
@@ -57,11 +57,11 @@ public function testHeaderIsRequiredToEnableTracing(): void
     public function testAddFtv1ExtensionMetaToResult(): void
     {
         $response = $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo { id }
             }
-            ',
+            GRAPHQL,
                 headers: ['apollo-federation-include-trace' => FederatedTracing::V1],
             );
 
@@ -152,11 +152,11 @@ public function testAddFtv1ExtensionMetaToBatchedResults(): void
     public function testReportErrorsToResult(): void
     {
         $response = $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo { bar }
             }
-            ',
+            GRAPHQL,
                 headers: ['apollo-federation-include-trace' => FederatedTracing::V1],
             );
 
diff --git a/tests/Integration/Validation/ExistsRuleTest.php b/tests/Integration/Validation/ExistsRuleTest.php
index eab6e14001..31e388bd5f 100644
--- a/tests/Integration/Validation/ExistsRuleTest.php
+++ b/tests/Integration/Validation/ExistsRuleTest.php
@@ -20,7 +20,7 @@ public function testExistsRule(): void
         $userInvalid->name = 'Tester';
         $userInvalid->save();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             callbackUser(id: ID! @eq): User @validator @find
             macroUser(id: ID! @eq): User @validator @find
@@ -29,7 +29,7 @@ public function testExistsRule(): void
         type User {
             id: ID!
         }
-        ';
+        GRAPHQL;
 
         $this->macroUser($userValid)
             ->assertGraphQLValidationPasses();
@@ -46,26 +46,26 @@ public function testExistsRule(): void
 
     private function macroUser(User $user): TestResponse
     {
-        return $this->graphQL(/** @lang GraphQL */ '
+        return $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             macroUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ]);
     }
 
     private function callbackUser(User $user): TestResponse
     {
-        return $this->graphQL(/** @lang GraphQL */ '
+        return $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: ID!) {
             callbackUser(id: $id) {
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ]);
     }
diff --git a/tests/Integration/Validation/RulesDirectiveTest.php b/tests/Integration/Validation/RulesDirectiveTest.php
index 9576d2f452..7f37c24214 100644
--- a/tests/Integration/Validation/RulesDirectiveTest.php
+++ b/tests/Integration/Validation/RulesDirectiveTest.php
@@ -23,20 +23,20 @@ protected function getEnvironmentSetUp($app): void
 
     public function testRequired(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(
-                required: String @rules(apply: ["required"])
-            ): Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(
+                        required: String @rules(apply: ["required"])
+                    ): Int
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(required: "foo")
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(required: "foo")
+                        }
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'foo' => Foo::THE_ANSWER,
@@ -44,11 +44,11 @@ public function testRequired(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['required']);
     }
 
@@ -58,24 +58,24 @@ public function testDifferentDates(): void
         $this->markTestSkipped('Not working right now, not sure how it can be fixed.');
 
         // @phpstan-ignore-next-line https://github.com/phpstan/phpstan-phpunit/issues/52
-        $this->schema = /** @lang GraphQL */ '
-        "A date string with format `Y-m-d`, e.g. `2011-05-23`."
-        scalar Date @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Date")
-
-        type Query {
-            foo(
-                bar: Date @rules(apply: ["different:baz"])
-                baz: Date
-            ): Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                "A date string with format `Y-m-d`, e.g. `2011-05-23`."
+                scalar Date @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Date")
+        
+                type Query {
+                    foo(
+                        bar: Date @rules(apply: ["different:baz"])
+                        baz: Date
+                    ): Int
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(bar: "2020-05-15", baz: "1999-12-01")
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(bar: "2020-05-15", baz: "1999-12-01")
+                        }
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'foo' => Foo::THE_ANSWER,
@@ -83,34 +83,34 @@ public function testDifferentDates(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(bar: "2020-05-15", baz: "2020-05-15")
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(bar: "2020-05-15", baz: "2020-05-15")
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['bar']);
     }
 
     public function testDateBefore(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        "A date string with format `Y-m-d`, e.g. `2011-05-23`."
-        scalar Date @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Date")
-
-        type Query {
-            foo(
-                early: Date @rules(apply: ["before:late"])
-                late: Date
-            ): Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                "A date string with format `Y-m-d`, e.g. `2011-05-23`."
+                scalar Date @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Date")
+        
+                type Query {
+                    foo(
+                        early: Date @rules(apply: ["before:late"])
+                        late: Date
+                    ): Int
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(early: "1999-12-01", late: "2020-05-15")
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(early: "1999-12-01", late: "2020-05-15")
+                        }
+            GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'foo' => Foo::THE_ANSWER,
@@ -118,105 +118,105 @@ public function testDateBefore(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(early: "2020-05-15", late: "1999-05-15")
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(early: "2020-05-15", late: "1999-05-15")
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['early']);
     }
 
     public function testCustomMessages(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(
-                bar: ID @rules(
-                    apply: ["required"]
-                    messages: [
-                        {
-                            rule: "required",
-                            message: "custom message"
-                        }
-                    ]
-                )
-            ): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(
+                        bar: ID @rules(
+                            apply: ["required"]
+                            messages: [
+                                {
+                                    rule: "required",
+                                    message: "custom message"
+                                }
+                            ]
+                        )
+                    ): String
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', 'custom message');
     }
 
     public function testCustomMessagesWithMap(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(
-                bar: ID @rules(
-                    apply: ["required"]
-                    messages: {
-                        required: "custom message"
-                    }
-                )
-            ): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(
+                        bar: ID @rules(
+                            apply: ["required"]
+                            messages: {
+                                required: "custom message"
+                            }
+                        )
+                    ): String
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', 'custom message');
     }
 
     public function testCustomAttributes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        input FooInput {
-            name: String @rules(
-                apply: ["required"]
-                attribute: "name"
-            )
-            type: FooTypeInput
-        }
-
-        input FooTypeInput {
-            name: String @rules(
-                apply: ["required"]
-                attribute: "name"
-            )
-            type: String @rules(apply: ["required"])
-        }
-
-        type Query {
-            foo(
-                bar: ID @rules(
-                    apply: ["required"]
-                    attribute: "baz"
-                )
-                emails: [String] @rulesForArray(
-                    apply: ["min:3"]
-                    attribute: "email list"
-                )
-                input: FooInput
-            ): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input FooInput {
+                    name: String @rules(
+                        apply: ["required"]
+                        attribute: "name"
+                    )
+                    type: FooTypeInput
+                }
+        
+                input FooTypeInput {
+                    name: String @rules(
+                        apply: ["required"]
+                        attribute: "name"
+                    )
+                    type: String @rules(apply: ["required"])
+                }
+        
+                type Query {
+                    foo(
+                        bar: ID @rules(
+                            apply: ["required"]
+                            attribute: "baz"
+                        )
+                        emails: [String] @rulesForArray(
+                            apply: ["min:3"]
+                            attribute: "email list"
+                        )
+                        input: FooInput
+                    ): String
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(emails: [], input: { type: {} })
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(emails: [], input: { type: {} })
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', 'The baz field is required.')
             ->assertGraphQLValidationError('emails', AppVersion::atLeast(10.0)
                 ? 'The email list field must have at least 3 items.'
@@ -228,28 +228,28 @@ public function testCustomAttributes(): void
 
     public function testUsesCustomRuleClass(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            withCustomRuleClass(
-                rules: String @rules(apply: ["Tests\\\\Utils\\\\Rules\\\\FooBarRule"])
-                rulesForArray: [String!]! @rulesForArray(apply: ["Tests\\\\Utils\\\\Rules\\\\FooBarRule"])
-            ): ID @mock
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    withCustomRuleClass(
+                        rules: String @rules(apply: ["Tests\\Utils\\Rules\\FooBarRule"])
+                        rulesForArray: [String!]! @rulesForArray(apply: ["Tests\\Utils\\Rules\\FooBarRule"])
+                    ): ID @mock
+                }
+        GRAPHQL;
 
         $this->mockResolverExpects(
             $this->never(),
         );
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                withCustomRuleClass(
-                    rules: "baz"
-                    rulesForArray: []
-                )
-            }
-            ',
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            withCustomRuleClass(
+                                rules: "baz"
+                                rulesForArray: []
+                            )
+                        }
+            GRAPHQL,
             )
             ->assertJsonFragment([
                 'rules' => [
@@ -266,20 +266,28 @@ public function testUsesCustomRuleClass(): void
     public function testValidateApplyArgument(string $applyArgument): void
     {
         $this->expectException(DefinitionException::class);
-        $this->buildSchema(/** @lang GraphQL */ "
-        type Query {
-            foo(bar: ID @rules(apply: {$applyArgument})): ID
-        }
-        ");
+        $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
+                type Query {
+                    foo(bar: ID @rules(apply: {$applyArgument})): ID
+                }
+        GRAPHQL);
     }
 
     /** @return iterable<array{string}> */
     public static function invalidApplyArguments(): iterable
     {
-        yield [/** @lang GraphQL */ '123'];
-        yield [/** @lang GraphQL */ '"123"'];
-        yield [/** @lang GraphQL */ '[]'];
-        yield [/** @lang GraphQL */ '[123]'];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        123
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        "123"
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        []
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [123]
+        GRAPHQL];
     }
 
     /** @dataProvider invalidMessageArguments */
@@ -287,56 +295,70 @@ public static function invalidApplyArguments(): iterable
     public function testValidateMessageArgument(string $messageArgument): void
     {
         $this->expectException(DefinitionException::class);
-        $this->buildSchema(/** @lang GraphQL */ "
-        type Query {
-            foo(bar: ID @rules(apply: [\"email\"], messages: {$messageArgument})): ID
-        }
-        ");
+        $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
+                type Query {
+                    foo(bar: ID @rules(apply: ["email"], messages: {$messageArgument})): ID
+                }
+        GRAPHQL);
     }
 
     /** @return iterable<array{string}> */
     public static function invalidMessageArguments(): iterable
     {
-        yield [/** @lang GraphQL */ '"foo"'];
-        yield [/** @lang GraphQL */ '{foo: 3}'];
-        yield [/** @lang GraphQL */ '[1, 2]'];
-        yield [/** @lang GraphQL */ '[{foo: 3}]'];
-        yield [/** @lang GraphQL */ '[{rule: "email"}]'];
-        yield [/** @lang GraphQL */ '[{rule: "email", message: null}]'];
-        yield [/** @lang GraphQL */ '[{rule: 3, message: "asfd"}]'];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        "foo"
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        {foo: 3}
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [1, 2]
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [{foo: 3}]
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [{rule: "email"}]
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [{rule: "email", message: null}]
+        GRAPHQL];
+        yield [/** @lang GraphQL */ <<<'GRAPHQL'
+        [{rule: 3, message: "asfd"}]
+        GRAPHQL];
     }
 
     public function testValidateElementsOfListType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(
-                bar: [String]
-                @rules(
-                    apply: ["required"]
-                )
-            ): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(
+                        bar: [String]
+                        @rules(
+                            apply: ["required"]
+                        )
+                    ): String
+                }
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(
-                    bar: ["", null, "bar"]
-                )
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(
+                                bar: ["", null, "bar"]
+                            )
+                        }
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['bar.0', 'bar.1']);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo(
-                    bar: []
-                )
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo(
+                                bar: []
+                            )
+                        }
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'foo' => Foo::THE_ANSWER,
@@ -344,11 +366,11 @@ public function testValidateElementsOfListType(): void
             ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
-            {
-                foo
-            }
-            ')
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
+                        {
+                            foo
+                        }
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'foo' => Foo::THE_ANSWER,
diff --git a/tests/Integration/Validation/RulesForArrayDirectiveTest.php b/tests/Integration/Validation/RulesForArrayDirectiveTest.php
index 0e990278df..1e835d3dde 100644
--- a/tests/Integration/Validation/RulesForArrayDirectiveTest.php
+++ b/tests/Integration/Validation/RulesForArrayDirectiveTest.php
@@ -8,29 +8,29 @@ final class RulesForArrayDirectiveTest extends TestCase
 {
     public function testValidatesListSize(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 list: [String]
                     @rulesForArray(apply: ["min:1"])
             ): ID
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     list: []
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['list']);
     }
 
     public function testValidatesListSizeOfInputObjects(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 list: [Foo]
@@ -41,16 +41,16 @@ public function testValidatesListSizeOfInputObjects(): void
         input Foo {
             bar: ID
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     list: []
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['list']);
     }
 }
diff --git a/tests/Integration/Validation/ValidationTest.php b/tests/Integration/Validation/ValidationTest.php
index e31e039fc1..839b848065 100644
--- a/tests/Integration/Validation/ValidationTest.php
+++ b/tests/Integration/Validation/ValidationTest.php
@@ -31,32 +31,32 @@ public function testRunsValidationBeforeCallingTheResolver(): void
             $this->never(),
         );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             doNotCall(
                 bar: String @rules(apply: ["required"])
             ): String @mock
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 doNotCall
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['bar']);
     }
 
     public function testFullValidationError(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: String @rules(apply: ["required"])
             ): Int
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
@@ -93,20 +93,20 @@ public function testFullValidationErrorWithoutLocationParse(): void
         $config = $this->app->make(ConfigRepository::class);
         $config->set('lighthouse.parse_source_location', false);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: String @rules(apply: ["required"])
             ): Int
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo
             }
-            ')
+            GRAPHQL)
             ->assertExactJson([
                 'errors' => [
                     [
@@ -129,7 +129,7 @@ public function testFullValidationErrorWithoutLocationParse(): void
 
     public function testRunsOnNonRootFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo @mock
         }
@@ -140,7 +140,7 @@ public function testRunsOnNonRootFields(): void
                 required: Int @rules(apply: ["required"])
             ): Int
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver([
             'bar' => 123,
@@ -148,14 +148,14 @@ public function testRunsOnNonRootFields(): void
         ]);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo {
                     bar
                     baz
                 }
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'foo' => [
@@ -181,24 +181,24 @@ public function testRunsOnNonRootFields(): void
 
     public function testCombinedRulesChangeTheirSemantics(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: Int @rules(apply: ["min:42"])
                 baz: Int @rules(apply: ["int", "min:42"])
             ): ID
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     bar: 21
                     baz: 21
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', AppVersion::atLeast(10.0)
                 ? 'The bar field must be at least 42 characters.'
                 : 'The bar must be at least 42 characters.')
@@ -209,7 +209,7 @@ public function testCombinedRulesChangeTheirSemantics(): void
 
     public function testValidatesDifferentPathsIndividually(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: String @rules(apply: ["email"])
@@ -221,10 +221,10 @@ public function testValidatesDifferentPathsIndividually(): void
             baz: String @rules(apply: ["email"])
             input: BazInput
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     bar: "invalid email"
@@ -240,7 +240,7 @@ public function testValidatesDifferentPathsIndividually(): void
                     ]
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys([
                 'bar',
                 'input.0.baz',
@@ -250,17 +250,17 @@ public function testValidatesDifferentPathsIndividually(): void
 
     public function testValidatesListContents(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 list: [String]
                     @rules(apply: ["required", "email"])
             ): ID
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     list: [
@@ -270,7 +270,7 @@ public function testValidatesListContents(): void
                     ]
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys([
                 'list.0',
                 'list.2',
@@ -281,7 +281,7 @@ public function testSanitizeValidateTransform(): void
     {
         $this->mockResolver(static fn ($_, array $args): string => $args['password']);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             password(
                 password: String
@@ -290,24 +290,24 @@ public function testSanitizeValidateTransform(): void
                     @hash
             ): String @mock
         }
-        ';
+        GRAPHQL;
 
-        $validPasswordResult = $this->graphQL(/** @lang GraphQL */ '
+        $validPasswordResult = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             password(password: " 1234567 ")
         }
-        ');
+        GRAPHQL);
         $password = $validPasswordResult->json('data.password');
 
         $this->assertNotSame(' 1234567 ', $password);
         $this->assertTrue(password_verify('1234567', $password));
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 password(password: " 1234 ")
             }
-            ')
+            GRAPHQL)
             ->assertJson([
                 'data' => [
                     'password' => null,
@@ -318,7 +318,7 @@ public function testSanitizeValidateTransform(): void
 
     public function testValidatesRulesOnInputObjectFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 input: FooInput
@@ -328,10 +328,10 @@ public function testValidatesRulesOnInputObjectFields(): void
         input FooInput {
             email: String @rules(apply: ["email"])
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -339,11 +339,11 @@ public function testValidatesRulesOnInputObjectFields(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationKeys(['input.email']);
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -351,13 +351,13 @@ public function testValidatesRulesOnInputObjectFields(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
     }
 
     public function testCombinesArgumentValidationWhenGrouped(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: String
@@ -365,24 +365,24 @@ public function testCombinesArgumentValidationWhenGrouped(): void
                     @rules(apply: ["max:3"])
             ): Int
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(bar: "f")
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', AppVersion::atLeast(10.0)
                 ? 'The bar field must be at least 2 characters.'
                 : 'The bar must be at least 2 characters.');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(bar: "fasdf")
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('bar', AppVersion::atLeast(10.0)
                 ? 'The bar field must not be greater than 3 characters.'
                 : 'The bar must not be greater than 3 characters.');
@@ -390,7 +390,7 @@ public function testCombinesArgumentValidationWhenGrouped(): void
 
     public function testSingleFieldReferencesAreQualified(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
@@ -399,10 +399,10 @@ public function testSingleFieldReferencesAreQualified(): void
             foo: String
             bar: String @rules(apply: ["required_if:foo,baz"])
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -410,11 +410,11 @@ public function testSingleFieldReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -422,13 +422,13 @@ public function testSingleFieldReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.bar', 'The input.bar field is required when input.foo is baz.');
     }
 
     public function testOptionalFieldReferencesAreQualified(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
@@ -437,10 +437,10 @@ public function testOptionalFieldReferencesAreQualified(): void
             foo: String @rules(apply: ["after:2018-01-01"])
             bar: String @rules(apply: ["after:foo"])
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -449,11 +449,11 @@ public function testOptionalFieldReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -462,7 +462,7 @@ public function testOptionalFieldReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.foo', AppVersion::atLeast(10.0)
                 ? 'The input.foo field must be a date after 2018-01-01.'
                 : 'The input.foo must be a date after 2018-01-01.')
@@ -481,7 +481,7 @@ public function testCustomValidationWithReferencesAreQualified(): void
 
         ValidatorFactory::replacer('equal_field', static fn (string $message, string $attribute, string $rule, array $parameters): string => str_replace(':other', implode(', ', $parameters), $message));
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
@@ -491,10 +491,10 @@ public function testCustomValidationWithReferencesAreQualified(): void
             bar: Int @rules(apply: ["with_reference:equal_field,0,foo"])
             baz: Int @rules(apply: ["with_reference:equal_field,0_1,foo,bar"])
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -504,11 +504,11 @@ public function testCustomValidationWithReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -518,7 +518,7 @@ public function testCustomValidationWithReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.bar', 'The input.bar must be equal to input.foo.')
             ->assertGraphQLValidationError('input.baz', 'The input.baz must be equal to input.foo, input.bar.');
     }
@@ -527,19 +527,19 @@ public function testCustomValidationClassWithReferencesAreQualified(): void
     {
         config(['app.debug' => true]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
 
-        input Custom @validator(class: "Tests\\\\Utils\\\\Validators\\\\EqualFieldCustomRuleValidator") {
+        input Custom @validator(class: "Tests\\Utils\\Validators\\EqualFieldCustomRuleValidator") {
             foo: Int
             bar: Int
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -548,13 +548,13 @@ public function testCustomValidationClassWithReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.bar', 'input');
     }
 
     public function testMultipleFieldReferencesAreQualified(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
@@ -564,10 +564,10 @@ public function testMultipleFieldReferencesAreQualified(): void
             bar: String @rules(apply: ["required_without_all:foo,baz"])
             baz: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -575,34 +575,34 @@ public function testMultipleFieldReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {}
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.bar', 'The input.bar field is required when none of input.foo / input.baz are present.');
     }
 
     public function testClosureRulesAreUsed(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Custom): String
         }
 
-        input Custom @validator(class: "Tests\\\\Utils\\\\Validators\\\\FooClosureValidator") {
+        input Custom @validator(class: "Tests\\Utils\\Validators\\FooClosureValidator") {
             foo: String!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -610,11 +610,11 @@ public function testClosureRulesAreUsed(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -622,13 +622,13 @@ public function testClosureRulesAreUsed(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.foo', FooClosureValidator::notFoo('input.foo'));
     }
 
     public function testReturnsMultipleValidationErrorsPerField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 input: FooInput
@@ -638,10 +638,10 @@ public function testReturnsMultipleValidationErrorsPerField(): void
         input FooInput {
             email: String @rules(apply: ["email", "min:16"])
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -649,7 +649,7 @@ public function testReturnsMultipleValidationErrorsPerField(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.email', AppVersion::atLeast(10.0)
                 ? 'The input.email field must be a valid email address.'
                 : 'The input.email must be a valid email address.')
diff --git a/tests/Integration/Validation/ValidatorDirectiveTest.php b/tests/Integration/Validation/ValidatorDirectiveTest.php
index fb15ea7e8a..997fb92d78 100644
--- a/tests/Integration/Validation/ValidatorDirectiveTest.php
+++ b/tests/Integration/Validation/ValidatorDirectiveTest.php
@@ -11,7 +11,7 @@ final class ValidatorDirectiveTest extends TestCase
 {
     public function testUsesValidatorByNamingConvention(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: SelfValidating): ID
         }
@@ -19,10 +19,10 @@ public function testUsesValidatorByNamingConvention(): void
         input SelfValidating @validator {
             rules: [String!]!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -30,7 +30,7 @@ public function testUsesValidatorByNamingConvention(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.rules', AppVersion::atLeast(10.0)
                 ? 'The input.rules field must be a valid email address.'
                 : 'The input.rules must be a valid email address.');
@@ -38,7 +38,7 @@ public function testUsesValidatorByNamingConvention(): void
 
     public function testUsesValidatorTwiceNested(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: FooInput): ID
         }
@@ -47,10 +47,10 @@ public function testUsesValidatorTwiceNested(): void
             email: String
             self: FooInput
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -61,7 +61,7 @@ public function testUsesValidatorTwiceNested(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.email', AppVersion::atLeast(10.0)
                 ? 'The input.email field must be a valid email address.'
                 : 'The input.email must be a valid email address.')
@@ -72,7 +72,7 @@ public function testUsesValidatorTwiceNested(): void
 
     public function testUsesSpecifiedValidatorClassWithoutNamespace(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Bar): ID
         }
@@ -80,10 +80,10 @@ public function testUsesSpecifiedValidatorClassWithoutNamespace(): void
         input Bar @validator(class: "SelfValidatingValidator") {
             rules: [String!]!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -91,7 +91,7 @@ public function testUsesSpecifiedValidatorClassWithoutNamespace(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.rules', AppVersion::atLeast(10.0)
                 ? 'The input.rules field must be a valid email address.'
                 : 'The input.rules must be a valid email address.');
@@ -99,18 +99,18 @@ public function testUsesSpecifiedValidatorClassWithoutNamespace(): void
 
     public function testUsesSpecifiedValidatorClassWithFullNamespace(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Bar): ID
         }
 
-        input Bar @validator(class: "Tests\\\\Utils\\\\Validators\\\\SelfValidatingValidator") {
+        input Bar @validator(class: "Tests\\Utils\\Validators\\SelfValidatingValidator") {
             rules: [String!]!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -118,7 +118,7 @@ public function testUsesSpecifiedValidatorClassWithFullNamespace(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.rules', AppVersion::atLeast(10.0)
                 ? 'The input.rules field must be a valid email address.'
                 : 'The input.rules must be a valid email address.');
@@ -126,7 +126,7 @@ public function testUsesSpecifiedValidatorClassWithFullNamespace(): void
 
     public function testNestedInputsRulesReceiveParameters(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: RulesWithParameters): ID
         }
@@ -138,10 +138,10 @@ public function testNestedInputsRulesReceiveParameters(): void
         input RulesWithParameters @validator {
             foo: [RuleWithParameter]!
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -151,7 +151,7 @@ public function testNestedInputsRulesReceiveParameters(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.foo.0.bar', AppVersion::atLeast(10.0)
                 ? 'The input.foo.0.bar field must contain 2 items.'
                 : 'The input.foo.0.bar must contain 2 items.');
@@ -159,7 +159,7 @@ public function testNestedInputsRulesReceiveParameters(): void
 
     public function testCustomMessage(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: EmailCustomMessage): ID
         }
@@ -167,10 +167,10 @@ public function testCustomMessage(): void
         input EmailCustomMessage @validator {
             email: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -178,13 +178,13 @@ public function testCustomMessage(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.email', EmailCustomMessageValidator::MESSAGE);
     }
 
     public function testCustomAttributes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: EmailCustomAttribute): ID
         }
@@ -192,10 +192,10 @@ public function testCustomAttributes(): void
         input EmailCustomAttribute @validator {
             email: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -203,7 +203,7 @@ public function testCustomAttributes(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.email', AppVersion::atLeast(10.0)
                 ? 'The email address field must be a valid email address.'
                 : 'The email address must be a valid email address.');
@@ -211,7 +211,7 @@ public function testCustomAttributes(): void
 
     public function testWithGlobalId(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: WithGlobalId!): ID
         }
@@ -219,13 +219,13 @@ public function testWithGlobalId(): void
         input WithGlobalId @validator {
             id: ID! @globalId
         }
-        ';
+        GRAPHQL;
 
         $encoder = $this->app->make(GlobalId::class);
         $globalId = $encoder->encode('asdf', '123');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($id: ID!) {
                 foo(
                     input: {
@@ -233,7 +233,7 @@ public function testWithGlobalId(): void
                     }
                 )
             }
-            ', [
+            GRAPHQL, [
                 'id' => $globalId,
             ])
             ->assertGraphQLValidationPasses();
@@ -241,20 +241,20 @@ public function testWithGlobalId(): void
 
     public function testFieldValidatorConvention(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(email: String): ID @validator
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     email: "not an email"
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('email', AppVersion::atLeast(10.0)
                 ? 'The email field must be a valid email address.'
                 : 'The email must be a valid email address.');
@@ -262,7 +262,7 @@ public function testFieldValidatorConvention(): void
 
     public function testFieldValidatorConventionOnExtendedType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: ID
         }
@@ -270,16 +270,16 @@ public function testFieldValidatorConventionOnExtendedType(): void
         extend type Query {
             foo(email: String): ID @validator
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     email: "not an email"
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('email', AppVersion::atLeast(10.0)
                 ? 'The email field must be a valid email address.'
                 : 'The email must be a valid email address.');
@@ -287,20 +287,20 @@ public function testFieldValidatorConventionOnExtendedType(): void
 
     public function testExplicitValidatorOnField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
-            bar(email: String): ID @validator(class: "Query\\\\FooValidator")
+            bar(email: String): ID @validator(class: "Query\\FooValidator")
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 bar(
                     email: "not an email"
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('email', AppVersion::atLeast(10.0)
                 ? 'The email field must be a valid email address.'
                 : 'The email must be a valid email address.');
@@ -308,7 +308,7 @@ public function testExplicitValidatorOnField(): void
 
     public function testArgumentReferencesAreQualified(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: BarRequiredWithoutFoo): String
         }
@@ -318,10 +318,10 @@ public function testArgumentReferencesAreQualified(): void
             bar: String
             baz: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {
@@ -329,17 +329,17 @@ public function testArgumentReferencesAreQualified(): void
                     }
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationPasses();
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(
                     input: {}
                 )
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLValidationError('input.bar', 'The input.bar field is required when input.foo is not present.');
     }
 }
diff --git a/tests/Integration/ValidationCachingTest.php b/tests/Integration/ValidationCachingTest.php
index 7fb0abe417..0cb2e88dff 100644
--- a/tests/Integration/ValidationCachingTest.php
+++ b/tests/Integration/ValidationCachingTest.php
@@ -20,11 +20,11 @@ public function testEnabled(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -35,11 +35,11 @@ public function testEnabled(): void
         $event->assertDispatchedTimes(KeyWritten::class, 1);
 
         // second request should be hit
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -58,11 +58,11 @@ public function testDisabled(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -81,11 +81,11 @@ public function testErrorsAreNotCached(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             bar
         }
-        ')->assertGraphQLErrorMessage('Cannot query field "bar" on type "Query".');
+        GRAPHQL)->assertGraphQLErrorMessage('Cannot query field "bar" on type "Query".');
 
         $event->assertDispatchedTimes(CacheMissed::class, 1);
         $event->assertDispatchedTimes(CacheHit::class, 0);
@@ -100,22 +100,22 @@ public function testDifferentQueriesHasDifferentKeys(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -134,11 +134,11 @@ public function testSameSchemaAndSameQueryHaveSameKeys(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -160,11 +160,11 @@ public function testSameSchemaAndSameQueryHaveSameKeys(): void
         $config->set('lighthouse.query_cache.enable', false);
         $config->set('lighthouse.validation_cache.enable', true);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -183,11 +183,11 @@ public function testDifferentSchemasHasDifferentKeys(): void
 
         $event = Event::fake();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -215,11 +215,11 @@ public function testDifferentSchemasHasDifferentKeys(): void
         $config->set('lighthouse.query_cache.enable', false);
         $config->set('lighthouse.validation_cache.enable', true);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertGraphQLErrorMessage('Cannot query field "foo" on type "Query".');
+        GRAPHQL)->assertGraphQLErrorMessage('Cannot query field "foo" on type "Query".');
 
         $event->assertDispatchedTimes(CacheMissed::class, 2);
         $event->assertDispatchedTimes(CacheHit::class, 0);
diff --git a/tests/Integration/WhereConditions/WhereConditionsDirectiveTest.php b/tests/Integration/WhereConditions/WhereConditionsDirectiveTest.php
index 38c3699af8..bfa75b35d8 100644
--- a/tests/Integration/WhereConditions/WhereConditionsDirectiveTest.php
+++ b/tests/Integration/WhereConditions/WhereConditionsDirectiveTest.php
@@ -17,7 +17,7 @@
 
 final class WhereConditionsDirectiveTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type User {
         id: ID!
         name: String
@@ -46,7 +46,7 @@ enum UserColumn {
         ID @enum(value: "id")
         NAME @enum(value: "name")
     }
-    ';
+    GRAPHQL;
 
     protected function getPackageProviders($app): array
     {
@@ -68,7 +68,7 @@ public function testBetweenWithMultipleVariables(): void
         $user2->date_of_birth = Carbon::createStrict(1995, 1, 1);
         $user2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($dobMin: Mixed, $dobMax: Mixed) {
             users(
                 where: {
@@ -80,7 +80,7 @@ public function testBetweenWithMultipleVariables(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'dobMin' => '1990-01-01',
             'dobMax' => '1999-01-01',
         ])->assertExactJson([
@@ -106,7 +106,7 @@ public function testBetweenWithOneVariable(): void
         $user2->date_of_birth = Carbon::createStrict(1995, 1, 1);
         $user2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($dates: Mixed) {
             users(
                 where: {
@@ -118,7 +118,7 @@ public function testBetweenWithOneVariable(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'dates' => ['1990-01-01', '1999-01-01'],
         ])->assertExactJson([
             'data' => [
@@ -143,7 +143,7 @@ public function testBetweenWithLiteralValues(): void
         $user2->date_of_birth = Carbon::createStrict(1995, 1, 1);
         $user2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query {
                 users(
                     where: {
@@ -155,7 +155,7 @@ public function testBetweenWithLiteralValues(): void
                     id
                 }
             }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -170,7 +170,7 @@ public function testDefaultsToWhereEqual(): void
     {
         factory(User::class, 2)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -181,14 +181,14 @@ public function testDefaultsToWhereEqual(): void
                 id
             }
         }
-        ')->assertJsonCount(1, 'data.users');
+        GRAPHQL)->assertJsonCount(1, 'data.users');
     }
 
     public function testOverwritesTheOperator(): void
     {
         factory(User::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -200,7 +200,7 @@ public function testOverwritesTheOperator(): void
                 id
             }
         }
-        ')->assertJsonCount(2, 'data.users');
+        GRAPHQL)->assertJsonCount(2, 'data.users');
     }
 
     public function testOperatorNotLike(): void
@@ -215,7 +215,7 @@ public function testOperatorNotLike(): void
         $user2->name = 'bar';
         $user2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -227,7 +227,7 @@ public function testOperatorNotLike(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -242,7 +242,7 @@ public function testOperatorIn(): void
     {
         factory(User::class, 5)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -254,7 +254,7 @@ public function testOperatorIn(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -280,7 +280,7 @@ public function testOperatorIsNull(): void
         $postWithBody->body = 'foobar';
         $postWithBody->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(
                 where: {
@@ -291,7 +291,7 @@ public function testOperatorIsNull(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'posts' => [
                     [
@@ -314,7 +314,7 @@ public function testOperatorNotNull(): void
         $postWithBody->body = 'foobar';
         $postWithBody->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(
                 where: {
@@ -325,7 +325,7 @@ public function testOperatorNotNull(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'posts' => [
                     [
@@ -340,7 +340,7 @@ public function testOperatorNotBetween(): void
     {
         factory(User::class, 5)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -352,7 +352,7 @@ public function testOperatorNotBetween(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -370,7 +370,7 @@ public function testAddsNestedAnd(): void
     {
         factory(User::class, 3)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -391,14 +391,14 @@ public function testAddsNestedAnd(): void
                 id
             }
         }
-        ')->assertJsonCount(1, 'data.users');
+        GRAPHQL)->assertJsonCount(1, 'data.users');
     }
 
     public function testAddsNestedOr(): void
     {
         factory(User::class, 5)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -426,7 +426,7 @@ public function testAddsNestedOr(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -447,7 +447,7 @@ public function testAddsNestedAndOr(): void
     {
         factory(User::class, 5)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -476,7 +476,7 @@ public function testAddsNestedAndOr(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -537,7 +537,7 @@ public function testHasMixed(): void
         $commentFive->comment = 'none';
         $commentFive->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -566,7 +566,7 @@ public function testHasMixed(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -598,7 +598,7 @@ public function testHasRelation(): void
         $commentTwo->comment = 'none';
         $commentTwo->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -610,7 +610,7 @@ public function testHasRelation(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -649,7 +649,7 @@ public function testHasAmount(): void
             $commentBatchTwo->save();
         }
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -662,7 +662,7 @@ public function testHasAmount(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -698,7 +698,7 @@ public function testHasOperator(): void
             $commentBatchTwo->save();
         }
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -712,7 +712,7 @@ public function testHasOperator(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -744,7 +744,7 @@ public function testHasCondition(): void
         $commentTwo->comment = 'none';
         $commentTwo->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -760,7 +760,7 @@ public function testHasCondition(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -792,7 +792,7 @@ public function testHasRecursive(): void
         $commentTwo->comment = 'none';
         $commentTwo->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -809,7 +809,7 @@ public function testHasRecursive(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -846,7 +846,7 @@ public function testHasNested(): void
         $task->user_id = 2;
         $task->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -868,7 +868,7 @@ public function testHasNested(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -881,13 +881,13 @@ public function testHasNested(): void
 
     public function testRejectsInvalidColumnName(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
                     AND: [
                         {
-                            column: "Robert\'); DROP TABLE Students;--"
+                            column: "Robert'); DROP TABLE Students;--"
                             value: "https://xkcd.com/327/"
                         }
                     ]
@@ -896,7 +896,7 @@ public function testRejectsInvalidColumnName(): void
                 id
             }
         }
-        ')->assertGraphQLErrorMessage(WhereConditionsHandler::invalidColumnName("Robert'); DROP TABLE Students;--"));
+        GRAPHQL)->assertGraphQLErrorMessage(WhereConditionsHandler::invalidColumnName("Robert'); DROP TABLE Students;--"));
     }
 
     public function testQueryForNull(): void
@@ -908,7 +908,7 @@ public function testQueryForNull(): void
         $userNamedNull->name = null;
         $userNamedNull->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -920,7 +920,7 @@ public function testQueryForNull(): void
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     [
@@ -934,7 +934,7 @@ public function testQueryForNull(): void
 
     public function testRequiresAValueForAColumn(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -944,7 +944,7 @@ public function testRequiresAValueForAColumn(): void
                 id
             }
         }
-        ')->assertGraphQLError(SQLOperator::missingValueForColumn('no_value'));
+        GRAPHQL)->assertGraphQLError(SQLOperator::missingValueForColumn('no_value'));
     }
 
     public function testOnlyAllowsWhitelistedColumns(): void
@@ -952,7 +952,7 @@ public function testOnlyAllowsWhitelistedColumns(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: Mixed!) {
             whitelistedColumns(
                 where: {
@@ -963,7 +963,7 @@ public function testOnlyAllowsWhitelistedColumns(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertExactJson([
             'data' => [
@@ -996,7 +996,7 @@ public function testUseColumnEnumsArg(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: Mixed!) {
             enumColumns(
                 where: {
@@ -1007,7 +1007,7 @@ enumColumns(
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $user->id,
         ])->assertExactJson([
             'data' => [
@@ -1025,7 +1025,7 @@ public function testIgnoreNullCondition(): void
         $user = factory(User::class)->create();
         $this->assertInstanceOf(User::class, $user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: null
@@ -1033,7 +1033,7 @@ public function testIgnoreNullCondition(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -1046,7 +1046,7 @@ public function testIgnoreNullCondition(): void
 
     public function testWhereConditionOnJSONColumn(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Location {
             id: Int!
         }
@@ -1054,7 +1054,7 @@ public function testWhereConditionOnJSONColumn(): void
         type Query {
             locations(where: _ @whereConditions): [Location!]! @all
         }
-        ';
+        GRAPHQL;
 
         $location = factory(Location::class)->make();
         $this->assertInstanceOf(Location::class, $location);
@@ -1065,7 +1065,7 @@ public function testWhereConditionOnJSONColumn(): void
 
         factory(Location::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             locations(
                 where: {
@@ -1076,7 +1076,7 @@ public function testWhereConditionOnJSONColumn(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'locations' => [
                     [
@@ -1100,7 +1100,7 @@ public function testHandler(): void
                 handler: "{$this->qualifyTestResolver('valueTwiceHandler')}")
             ): [User!]! @all
         }
-GRAPHQL;
+        GRAPHQL;
 
         $user1 = factory(User::class)->make();
         $this->assertInstanceOf(User::class, $user1);
@@ -1112,7 +1112,7 @@ public function testHandler(): void
         $user2->name = 'foofoo';
         $user2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 where: {
@@ -1123,7 +1123,7 @@ public function testHandler(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -1150,7 +1150,7 @@ public function testWhereHasConditionsColumnDefaultsToString(): void
         $post2->user()->associate($user2);
         $post2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             enumColumns(
                 where: {
@@ -1166,7 +1166,7 @@ enumColumns(
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'enumColumns' => [
                     [
@@ -1203,7 +1203,7 @@ public function testWhereHasConditionsWithNestedHas(): void
         $comment2->post()->associate($post2);
         $comment2->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             enumColumns(
                 where: {
@@ -1224,7 +1224,7 @@ enumColumns(
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'enumColumns' => [
                     [
@@ -1262,7 +1262,7 @@ public function testWhereHasConditionsWithAndOr(): void
         $post3->save();
 
         // Find users with posts where (title = 'First' OR title = 'Second') AND body = 'Alpha'
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             enumColumns(
                 where: {
@@ -1285,7 +1285,7 @@ enumColumns(
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'enumColumns' => [
                     [
diff --git a/tests/Integration/WhereConditions/WhereHasConditionsDirectiveTest.php b/tests/Integration/WhereConditions/WhereHasConditionsDirectiveTest.php
index ee533b0554..cb05baf354 100644
--- a/tests/Integration/WhereConditions/WhereHasConditionsDirectiveTest.php
+++ b/tests/Integration/WhereConditions/WhereHasConditionsDirectiveTest.php
@@ -12,7 +12,7 @@
 
 final class WhereHasConditionsDirectiveTest extends DBTestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type User {
         id: ID!
         name: String
@@ -78,7 +78,7 @@ final class WhereHasConditionsDirectiveTest extends DBTestCase
             hasChildren: _ @whereHasConditions(columns: ["id"])
         ): [Location!]! @all
     }
-    ';
+    GRAPHQL;
 
     protected function getPackageProviders($app): array
     {
@@ -97,7 +97,7 @@ public function testExistenceWithEmptyCondition(): void
 
         factory(User::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 hasCompany: {}
@@ -105,7 +105,7 @@ public function testExistenceWithEmptyCondition(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -120,7 +120,7 @@ public function testIgnoreNullCondition(): void
     {
         factory(User::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 hasCompany: null
@@ -128,7 +128,7 @@ public function testIgnoreNullCondition(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -143,7 +143,7 @@ public function testWithoutRelationName(): void
     {
         factory(User::class)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             withoutRelation(
                 hasCompany: {
@@ -154,7 +154,7 @@ public function testWithoutRelationName(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'withoutRelation' => [
                     [
@@ -169,7 +169,7 @@ public function testOperatorOr(): void
     {
         factory(User::class, 5)->create();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(
                 hasCompany: {
@@ -188,7 +188,7 @@ public function testOperatorOr(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     [
@@ -214,7 +214,7 @@ public function testWhereHasBelongsToMany(): void
 
         $user->roles()->attach($role);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($id: Mixed!) {
             users(
                 hasRoles: {
@@ -225,7 +225,7 @@ public function testWhereHasBelongsToMany(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'id' => $role->getKey(),
         ])->assertExactJson([
             'data' => [
@@ -274,7 +274,7 @@ public function testWhereHasBelongsToManyOrNestedConditions(): void
         $postWithCategoryWithParentWithFooPosts = factory(Post::class)->create();
         $postWithCategoryWithParentWithFooPosts->categories()->attach($categoryWithParentWithFooPosts);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(
                 hasCategories: {
@@ -290,7 +290,7 @@ public function testWhereHasBelongsToManyOrNestedConditions(): void
                 id
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'posts' => [
                     [
@@ -335,7 +335,7 @@ public function testWhereHasNestedRelationWithDotNotation(): void
         $post5 = factory(Post::class)->create();
         $post5->categories()->attach($category5);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($categoryId: Mixed!) {
             posts(
                 hasCategories: {
@@ -372,7 +372,7 @@ public function testWhereHasNestedRelationWithDotNotation(): void
                 id
             }
         }
-        ', [
+        GRAPHQL, [
             'categoryId' => $category3->getKey(),
         ])->assertExactJson([
             'data' => [
@@ -410,7 +410,7 @@ public function testWhereConditionsHasNestedTables(): void
         $post = factory(Post::class)->create();
         $post->categories()->attach($category4);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($hasCategories: WhereConditions) {
             posts(hasCategories: $hasCategories) {
                 id
@@ -434,7 +434,7 @@ public function testWhereConditionsHasNestedTables(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'hasCategories' => [
                 'HAS' => [
                     'relation' => 'parent.parent.parent',
@@ -485,7 +485,7 @@ public function testWhereHasBelongsToSameTableRelationship(): void
         $child->parent()->associate($parent);
         $child->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($hasParent: QueryLocationsHasParentWhereHasConditions) {
             locations(hasParent: $hasParent) {
                 id
@@ -497,7 +497,7 @@ public function testWhereHasBelongsToSameTableRelationship(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'hasParent' => [
                 'column' => 'ID',
                 'value' => $parent->id,
@@ -527,7 +527,7 @@ public function testWhereHasHasManySameTableRelationship(): void
         $child->parent()->associate($parent);
         $child->save();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($hasChildren: QueryLocationsHasChildrenWhereHasConditions) {
             locations(hasChildren: $hasChildren) {
                 id
@@ -539,7 +539,7 @@ public function testWhereHasHasManySameTableRelationship(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'hasChildren' => [
                 'column' => 'ID',
                 'value' => $child->id,
diff --git a/tests/Unit/Auth/AuthDirectiveTest.php b/tests/Unit/Auth/AuthDirectiveTest.php
index 2bae425dff..7b9a06c13b 100644
--- a/tests/Unit/Auth/AuthDirectiveTest.php
+++ b/tests/Unit/Auth/AuthDirectiveTest.php
@@ -15,7 +15,7 @@ public function testResolveAuthenticatedUser(): void
         $user->name = 'foo';
         $this->be($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -23,15 +23,15 @@ public function testResolveAuthenticatedUser(): void
         type Query {
             user: User! @auth
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => $user->name,
@@ -48,7 +48,7 @@ public function testResolveAuthenticatedUserWithGuardsArgument(): void
         $authFactory = $this->app->make(AuthFactory::class);
         $authFactory->guard('web')->setUser($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -56,15 +56,15 @@ public function testResolveAuthenticatedUserWithGuardsArgument(): void
         type Query {
             user: User! @auth(guards: ["web"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => $user->name,
@@ -94,7 +94,7 @@ public function testResolveAuthenticatedUserWithMultipleGuardsArgument(): void
         $authFactory = $this->app->make(AuthFactory::class);
         $authFactory->guard('api')->setUser($user);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -102,15 +102,15 @@ public function testResolveAuthenticatedUserWithMultipleGuardsArgument(): void
         type Query {
             user: User! @auth(guards: ["web", "api"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => $user->name,
diff --git a/tests/Unit/Auth/CanDirectiveTest.php b/tests/Unit/Auth/CanDirectiveTest.php
index 3be9f83080..47e665299e 100644
--- a/tests/Unit/Auth/CanDirectiveTest.php
+++ b/tests/Unit/Auth/CanDirectiveTest.php
@@ -15,7 +15,7 @@ public function testThrowsIfNotAuthorized(): void
     {
         $this->be(new User());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "adminOnly")
@@ -25,22 +25,22 @@ public function testThrowsIfNotAuthorized(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
     }
 
     public function testThrowsWithCustomMessageIfNotAuthorized(): void
     {
         $this->be(new User());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "superAdminOnly")
@@ -50,16 +50,16 @@ public function testThrowsWithCustomMessageIfNotAuthorized(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     name
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(UserPolicy::SUPER_ADMINS_ONLY_MESSAGE);
     }
 
@@ -67,7 +67,7 @@ public function testThrowsFirstWithCustomMessageIfNotAuthorized(): void
     {
         $this->be(new User());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: ["superAdminOnly", "adminOnly"])
@@ -77,16 +77,16 @@ public function testThrowsFirstWithCustomMessageIfNotAuthorized(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     name
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(UserPolicy::SUPER_ADMINS_ONLY_MESSAGE);
     }
 
@@ -98,7 +98,7 @@ public function testPassesAuthIfAuthorized(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "adminOnly")
@@ -108,15 +108,15 @@ public function testPassesAuthIfAuthorized(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -133,7 +133,7 @@ public function testChecksAgainstResolvedModels(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "view", resolved: true)
@@ -143,15 +143,15 @@ public function testChecksAgainstResolvedModels(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -164,7 +164,7 @@ public function testAcceptsGuestUser(): void
     {
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "guestOnly")
@@ -174,15 +174,15 @@ public function testAcceptsGuestUser(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -199,7 +199,7 @@ public function testPassesMultiplePolicies(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: ["adminOnly", "alwaysTrue"])
@@ -209,15 +209,15 @@ public function testPassesMultiplePolicies(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -228,7 +228,7 @@ public function testPassesMultiplePolicies(): void
 
     public function testProcessesTheArgsArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User!
                 @can(ability: "dependingOnArg", args: [false])
@@ -238,15 +238,15 @@ public function testProcessesTheArgsArgument(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(AuthorizationException::MESSAGE);
     }
 
     public function testInjectArgsPassesClientArgumentToPolicy(): void
@@ -255,7 +255,7 @@ public function testInjectArgsPassesClientArgumentToPolicy(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(foo: String): User!
                 @can(ability: "injectArgs", injectArgs: true)
@@ -265,15 +265,15 @@ public function testInjectArgsPassesClientArgumentToPolicy(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(foo: "bar") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -288,7 +288,7 @@ public function testChecksAgainstRootModel(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(foo: String): User! @mock
         }
@@ -297,16 +297,16 @@ public function testChecksAgainstRootModel(): void
             name: String @can(ability: "view", root: true)
             email: String @can(ability: "superAdminOnly", root: true)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(foo: "bar") {
                 name
                 email
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -324,7 +324,7 @@ public function testInjectedArgsAndStaticArgs(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(foo: String): User!
                 @can(
@@ -338,15 +338,15 @@ public function testInjectedArgsAndStaticArgs(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(foo: "dynamic") {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => 'foo',
@@ -367,10 +367,10 @@ public static function resolveUser(): User
     public function testThrowsIfResolvedIsUsedOnMutation(): void
     {
         $this->expectExceptionObject(CanDirective::resolvedIsUnsafeInMutations('foo'));
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo: ID @can(resolved: true)
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Auth/CanDirectiveTestBase.php b/tests/Unit/Auth/CanDirectiveTestBase.php
index 32c954ad7d..91db49686a 100644
--- a/tests/Unit/Auth/CanDirectiveTestBase.php
+++ b/tests/Unit/Auth/CanDirectiveTestBase.php
@@ -14,13 +14,13 @@ abstract public static function getSchema(string $commonArgs): string;
 
     protected function getQuery(): string
     {
-        return /** @lang GraphQL */ '
+        return /** @lang GraphQL */ <<<'GRAPHQL'
             query ($foo: String) {
                 user(foo: $foo) {
                     name
                 }
             }
-        ';
+        GRAPHQL;
     }
 
     protected function query(?string $foo = null): TestResponse
diff --git a/tests/Unit/Auth/CanModelDirectiveTest.php b/tests/Unit/Auth/CanModelDirectiveTest.php
index fb12a9a7aa..b79f0ebbf1 100644
--- a/tests/Unit/Auth/CanModelDirectiveTest.php
+++ b/tests/Unit/Auth/CanModelDirectiveTest.php
@@ -6,7 +6,7 @@ final class CanModelDirectiveTest extends CanDirectiveTestBase
 {
     public static function getSchema(string $commonArgs): string
     {
-        return /** @lang GraphQL */ "
+        return /** @lang GraphQL */ <<<GRAPHQL
             type Query {
                 user(foo: String): User
                     @canModel({$commonArgs})
@@ -16,6 +16,6 @@ public static function getSchema(string $commonArgs): string
             type User {
                 name: String
             }
-        ";
+        GRAPHQL;
     }
 }
diff --git a/tests/Unit/Auth/CanResolvedDirectiveTest.php b/tests/Unit/Auth/CanResolvedDirectiveTest.php
index 46f2f7b48f..c064635164 100644
--- a/tests/Unit/Auth/CanResolvedDirectiveTest.php
+++ b/tests/Unit/Auth/CanResolvedDirectiveTest.php
@@ -10,7 +10,7 @@ final class CanResolvedDirectiveTest extends CanDirectiveTestBase
 {
     public static function getSchema(string $commonArgs): string
     {
-        return /** @lang GraphQL */ "
+        return /** @lang GraphQL */ <<<GRAPHQL
             type Query {
                 user(foo: String): User
                     @canResolved({$commonArgs})
@@ -20,7 +20,7 @@ public static function getSchema(string $commonArgs): string
             type User {
                 name: String
             }
-        ";
+        GRAPHQL;
     }
 
     public function testThrowsIfNotAuthorized(): void
diff --git a/tests/Unit/Auth/CanRootDirectiveTest.php b/tests/Unit/Auth/CanRootDirectiveTest.php
index 70130bc0f7..6232de008e 100644
--- a/tests/Unit/Auth/CanRootDirectiveTest.php
+++ b/tests/Unit/Auth/CanRootDirectiveTest.php
@@ -10,7 +10,7 @@ final class CanRootDirectiveTest extends CanDirectiveTestBase
 {
     public static function getSchema(string $commonArgs): string
     {
-        return /** @lang GraphQL */ "
+        return /** @lang GraphQL */ <<<GRAPHQL
             type Query {
                 user: User!
                     @mock
@@ -19,18 +19,18 @@ public static function getSchema(string $commonArgs): string
             type User {
                 name(foo: String): String @canRoot({$commonArgs})
             }
-        ";
+        GRAPHQL;
     }
 
     protected function getQuery(): string
     {
-        return /** @lang GraphQL */ '
+        return /** @lang GraphQL */ <<<'GRAPHQL'
             query ($foo: String) {
                 user {
                     name (foo: $foo)
                 }
             }
-        ';
+        GRAPHQL;
     }
 
     public function testThrowsIfNotAuthorized(): void
@@ -156,7 +156,7 @@ public function testGlobalGate(): void
 
         $this->mockResolver(fn (): User => $this->resolveUser());
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
             type Query {
                 user: User!
                     @canRoot(ability: "globalAdmin")
@@ -166,7 +166,7 @@ public function testGlobalGate(): void
             type User {
                 name(foo: String): String
             }
-        ';
+        GRAPHQL;
 
         $this->query()->assertJson([
             'data' => [
diff --git a/tests/Unit/Auth/GuardDirectiveTest.php b/tests/Unit/Auth/GuardDirectiveTest.php
index 330ecce455..db31724399 100644
--- a/tests/Unit/Auth/GuardDirectiveTest.php
+++ b/tests/Unit/Auth/GuardDirectiveTest.php
@@ -13,32 +13,32 @@ final class GuardDirectiveTest extends TestCase
 {
     public function testGuardDefault(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @guard
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
+        GRAPHQL)->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
     }
 
     public function testGuardWith(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @guard(with: ["web"])
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'errors' => [
                 [
                     'message' => AuthenticationException::MESSAGE,
@@ -54,19 +54,19 @@ public function testGuardWith(): void
 
     public function testPassesOneFieldButThrowsInAnother(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int
             bar: String @guard
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
             bar
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
                 'bar' => null,
@@ -84,7 +84,7 @@ public function testPassesOneFieldButThrowsInAnother(): void
 
     public function testGuardHappensBeforeOtherDirectivesIfAddedFromType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query @guard {
             user: User!
                 @can(ability: "adminOnly")
@@ -94,16 +94,16 @@ public function testGuardHappensBeforeOtherDirectivesIfAddedFromType(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 user {
                     name
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
     }
 
@@ -112,7 +112,7 @@ public function testGuardAppliesToFieldsOnExtendTypeOnly(): void
         $value = 42;
         $this->mockResolver($value);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             unguarded: Int! @mock
         }
@@ -120,20 +120,20 @@ public function testGuardAppliesToFieldsOnExtendTypeOnly(): void
         extend type Query @guard {
             guarded: Int! @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 guarded
             }
-            ')
+        GRAPHQL)
             ->assertGraphQLErrorMessage(AuthenticationException::MESSAGE);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 unguarded
             }
-            ')
+        GRAPHQL)
             ->assertExactJson([
                 'data' => [
                     'unguarded' => $value,
@@ -166,7 +166,7 @@ public function testMultiGuardWithAuthorization(): void
 
         $this->mockResolver($team);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Team {
             id: ID!
         }
@@ -174,18 +174,18 @@ public function testMultiGuardWithAuthorization(): void
         type Query {
             team: Team!
                 @guard(with: ["team"])
-                @can(ability: "onlyTeams", model: "Tests\\\\Utils\\\\Models\\\\Team")
+                @can(ability: "onlyTeams", model: "Tests\\Utils\\Models\\Team")
                 @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             team {
                 id
             }
         }
-        ')
+        GRAPHQL)
             ->assertGraphQLErrorFree()
             ->assertJson([
                 'data' => [
diff --git a/tests/Unit/Auth/UserContextTest.php b/tests/Unit/Auth/UserContextTest.php
index 44eda831f9..439714126e 100644
--- a/tests/Unit/Auth/UserContextTest.php
+++ b/tests/Unit/Auth/UserContextTest.php
@@ -15,7 +15,7 @@ protected function setUp(): void
     {
         parent::setUp();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String!
         }
@@ -23,7 +23,7 @@ protected function setUp(): void
         type Query {
             user: User @mock
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args, GraphQLContext $context): ?Authenticatable => $context->user());
     }
@@ -34,13 +34,13 @@ public function testResolveAuthenticatedUserUsingContext(): void
         $user->name = 'foo';
         $this->be($user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => $user->name,
@@ -51,13 +51,13 @@ public function testResolveAuthenticatedUserUsingContext(): void
 
     public function testResolveGuestUserUsingContext(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => null,
             ],
@@ -87,13 +87,13 @@ public function testResolveAuthenticatedUserUsingContextWithMultipleGuards(): vo
         $authFactory = $this->app->make(AuthFactory::class);
         $authFactory->guard('api')->setUser($user);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'name' => $user->name,
diff --git a/tests/Unit/Deprecation/DeprecationTest.php b/tests/Unit/Deprecation/DeprecationTest.php
index 94a215d170..5cff22dc6a 100644
--- a/tests/Unit/Deprecation/DeprecationTest.php
+++ b/tests/Unit/Deprecation/DeprecationTest.php
@@ -32,17 +32,17 @@ protected function tearDown(): void
 
     public function testDetectsDeprecatedFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @deprecated
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -55,17 +55,17 @@ public function testDetectsDeprecatedFields(): void
 
     public function testDetectsDeprecatedFieldWithReason(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @deprecated(reason: "bar")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -78,18 +78,18 @@ public function testDetectsDeprecatedFieldWithReason(): void
 
     public function testDetectsDeprecatedFieldsMultipleTimes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @deprecated
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
             bar: foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
                 'bar' => Foo::THE_ANSWER,
@@ -103,7 +103,7 @@ public function testDetectsDeprecatedFieldsMultipleTimes(): void
 
     public function testDetectsDeprecatedEnumValueUsage(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         enum Foo {
             A
             B @deprecated
@@ -112,13 +112,13 @@ enum Foo {
         type Query {
             foo(foo: Foo): Int
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(foo: B)
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -132,7 +132,7 @@ enum Foo {
     /** @return never */
     public function testDetectsDeprecatedEnumValueUsageInVariables(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         enum Foo {
             A
             B @deprecated
@@ -141,13 +141,13 @@ enum Foo {
         type Query {
             foo(foo: Foo): Int
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($foo: Foo!) {
             foo(foo: $foo)
         }
-        ', [
+        GRAPHQL, [
             'foo' => 'B',
         ])->assertExactJson([
             'data' => [
@@ -163,7 +163,7 @@ public function testDetectsDeprecatedEnumValueUsageInResults(): void
     {
         $this->mockResolver('B');
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         enum Foo {
             A
             B @deprecated
@@ -172,13 +172,13 @@ enum Foo {
         type Query {
             foo: Foo @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => 'B',
             ],
diff --git a/tests/Unit/Events/BuildSchemaStringTest.php b/tests/Unit/Events/BuildSchemaStringTest.php
index cd64d2e6ff..723bab0c01 100644
--- a/tests/Unit/Events/BuildSchemaStringTest.php
+++ b/tests/Unit/Events/BuildSchemaStringTest.php
@@ -27,28 +27,28 @@ public function testAddAdditionalSchemaThroughEvent(): void
             }
         ");
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Query {
-            foo: String @field(resolver: \"{$this->qualifyTestResolver('resolveFoo')}\")
+            foo: String @field(resolver: "{$this->qualifyTestResolver('resolveFoo')}")
         }
-        ";
+        GRAPHQL;
 
-        $queryForBaseSchema = /** @lang GraphQL */ '
+        $queryForBaseSchema = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ';
+        GRAPHQL;
         $this->graphQL($queryForBaseSchema)->assertJson([
             'data' => [
                 'foo' => 'foo',
             ],
         ]);
 
-        $queryForAdditionalSchema = /** @lang GraphQL */ '
+        $queryForAdditionalSchema = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             sayHello
         }
-        ';
+        GRAPHQL;
         $this->graphQL($queryForAdditionalSchema)->assertJson([
             'data' => [
                 'sayHello' => 'hello',
diff --git a/tests/Unit/Events/ManipulateASTTest.php b/tests/Unit/Events/ManipulateASTTest.php
index 828eece792..bfd77d834c 100644
--- a/tests/Unit/Events/ManipulateASTTest.php
+++ b/tests/Unit/Events/ManipulateASTTest.php
@@ -11,11 +11,11 @@ final class ManipulateASTTest extends TestCase
 {
     public function testManipulateTheAST(): void
     {
-        $this->schema = '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: String
         }
-        ';
+        GRAPHQL;
 
         Event::listen(ManipulateAST::class, static function (ManipulateAST $manipulateAST): void {
             $manipulateAST->documentAST->setTypeDefinition(
@@ -23,11 +23,11 @@ public function testManipulateTheAST(): void
             );
         });
 
-        $this->graphQL('
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => 42,
             ],
diff --git a/tests/Unit/Events/ManipulateResultTest.php b/tests/Unit/Events/ManipulateResultTest.php
index 007476fffe..768dba6dc2 100644
--- a/tests/Unit/Events/ManipulateResultTest.php
+++ b/tests/Unit/Events/ManipulateResultTest.php
@@ -20,11 +20,11 @@ static function (ManipulateResult $manipulateResult): void {
             },
         );
 
-        $this->graphQL('
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER + 1,
             ],
diff --git a/tests/Unit/Execution/Arguments/ArgumentSetFactoryTest.php b/tests/Unit/Execution/Arguments/ArgumentSetFactoryTest.php
index 0b9ada21c2..bc35386fda 100644
--- a/tests/Unit/Execution/Arguments/ArgumentSetFactoryTest.php
+++ b/tests/Unit/Execution/Arguments/ArgumentSetFactoryTest.php
@@ -18,11 +18,11 @@ final class ArgumentSetFactoryTest extends TestCase
 {
     public function testSimpleField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: Int): Int
         }
-        ';
+        GRAPHQL;
 
         $argumentSet = $this->rootQueryArgumentSet([
             'bar' => 123,
@@ -36,11 +36,11 @@ public function testSimpleField(): void
 
     public function testNullableList(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: [Int!]): Int
         }
-        ';
+        GRAPHQL;
 
         $argumentSet = $this->rootQueryArgumentSet([
             'bar' => null,
@@ -54,7 +54,7 @@ public function testNullableList(): void
 
     public function testItsListsAllTheWayDown(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar:
                 # Level 1
@@ -72,7 +72,7 @@ public function testItsListsAllTheWayDown(): void
                 ]
             ): Int
         }
-        ';
+        GRAPHQL;
 
         // Level 1
         $barValue = [
@@ -125,7 +125,7 @@ public function testItsListsAllTheWayDown(): void
 
     public function testNullableInputObject(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: Bar): Int
         }
@@ -133,7 +133,7 @@ public function testNullableInputObject(): void
         input Bar {
             baz: ID
         }
-        ';
+        GRAPHQL;
 
         $argumentSet = $this->rootQueryArgumentSet([
             'bar' => null,
@@ -147,11 +147,11 @@ public function testNullableInputObject(): void
 
     public function testWithUndefined(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: ID): Int
         }
-        ';
+        GRAPHQL;
 
         $argumentSet = $this->rootQueryArgumentSet([]);
 
diff --git a/tests/Unit/Execution/Arguments/Fixtures/Nested.php b/tests/Unit/Execution/Arguments/Fixtures/Nested.php
index 30b953334b..4a8014369a 100644
--- a/tests/Unit/Execution/Arguments/Fixtures/Nested.php
+++ b/tests/Unit/Execution/Arguments/Fixtures/Nested.php
@@ -11,6 +11,8 @@ public function __invoke(mixed $root, $args): void {}
 
     public static function definition(): string
     {
-        return /** @lang GraphQL */ 'directive @nested on FIELD_DEFINITION';
+        return /** @lang GraphQL */ <<<'GRAPHQL'
+        directive @nested on FIELD_DEFINITION
+        GRAPHQL;
     }
 }
diff --git a/tests/Unit/Execution/CreatesContextTest.php b/tests/Unit/Execution/CreatesContextTest.php
index fbfec4bb78..9ec193a8f9 100644
--- a/tests/Unit/Execution/CreatesContextTest.php
+++ b/tests/Unit/Execution/CreatesContextTest.php
@@ -30,17 +30,17 @@ public function testGenerateCustomContext(): void
             return $context->foo();
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             context: String @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             context
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'context' => FooContext::FROM_FOO_CONTEXT,
             ],
diff --git a/tests/Unit/Federation/ExternalDirectiveTest.php b/tests/Unit/Federation/ExternalDirectiveTest.php
index a421a53c59..f6cfabc22f 100644
--- a/tests/Unit/Federation/ExternalDirectiveTest.php
+++ b/tests/Unit/Federation/ExternalDirectiveTest.php
@@ -21,7 +21,7 @@ public function testExternalDirectiveForwardsScalars(): void
 
         $this->mockResolver($id);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo! @mock
         }
@@ -29,15 +29,15 @@ public function testExternalDirectiveForwardsScalars(): void
         type Foo @key(fields: "id") {
             id: ID! @external
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'id' => $id,
@@ -52,7 +52,7 @@ public function testExternalDirectiveForwardsScalarsWithinIterable(): void
         $two = 2;
         $this->mockResolver([$one, $two]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foos: [Foo!]! @mock
         }
@@ -60,15 +60,15 @@ public function testExternalDirectiveForwardsScalarsWithinIterable(): void
         type Foo @key(fields: "id") {
             id: ID! @external
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foos {
                 id
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foos' => [
                     [
@@ -90,7 +90,7 @@ public function testExternalDirectiveFallbackToDefaultFieldResolver(): void
         ];
         $this->mockResolver($foo);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo! @mock
         }
@@ -99,16 +99,16 @@ public function testExternalDirectiveFallbackToDefaultFieldResolver(): void
             id: ID! @external
             someFieldWeOwn: String!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 id
                 someFieldWeOwn
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => $foo,
             ],
diff --git a/tests/Unit/Federation/SchemaBuilderTest.php b/tests/Unit/Federation/SchemaBuilderTest.php
index 27e41b211a..5eb3e43e80 100644
--- a/tests/Unit/Federation/SchemaBuilderTest.php
+++ b/tests/Unit/Federation/SchemaBuilderTest.php
@@ -20,7 +20,7 @@ protected function getPackageProviders($app): array
 
     public function testFederatedSchema(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
             id: ID!
             foo: String!
@@ -29,7 +29,7 @@ public function testFederatedSchema(): void
         type Query {
             foo: Int
         }
-        ');
+        GRAPHQL);
 
         $this->assertTrue($schema->hasType('_Entity'));
         $this->assertTrue($schema->hasType('_Service'));
@@ -42,12 +42,12 @@ public function testFederatedSchema(): void
 
     public function testAddsQueryTypeIfNotDefined(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
             id: ID!
             foo: String!
         }
-        ');
+        GRAPHQL);
 
         $this->assertSchemaHasQueryTypeWithFederationFields($schema);
     }
diff --git a/tests/Unit/Federation/SchemaValidatorTest.php b/tests/Unit/Federation/SchemaValidatorTest.php
index 7e3ad0c3e6..ef64d61069 100644
--- a/tests/Unit/Federation/SchemaValidatorTest.php
+++ b/tests/Unit/Federation/SchemaValidatorTest.php
@@ -21,11 +21,11 @@ protected function getPackageProviders($app): array
 
     public function testHooksIntoValidateSchemaCommand(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "not_defined_on_the_object_type") {
           id: ID!
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
         $tester = $this->commandTester(new ValidateSchemaCommand());
 
         $this->expectException(FederationException::class);
@@ -34,11 +34,11 @@ public function testHooksIntoValidateSchemaCommand(): void
 
     public function testValidatesSuccessfully(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") {
           id: ID!
         }
-        ');
+        GRAPHQL);
 
         $validator = $this->app->make(SchemaValidator::class);
         $validator->handle(new ValidateSchema($schema));
@@ -47,11 +47,11 @@ public function testValidatesSuccessfully(): void
 
     public function testValidatesUsesFieldNodes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "...{ id }") {
           id: ID!
         }
-        ');
+        GRAPHQL);
 
         $validator = $this->app->make(SchemaValidator::class);
         $this->expectException(FederationException::class);
@@ -60,11 +60,11 @@ public function testValidatesUsesFieldNodes(): void
 
     public function testValidatesMissingExternalDirective(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id") @extends {
           id: ID! @mock
         }
-        ');
+        GRAPHQL);
 
         $validator = $this->app->make(SchemaValidator::class);
         $this->expectException(FederationException::class);
@@ -73,7 +73,7 @@ public function testValidatesMissingExternalDirective(): void
 
     public function testValidatesNestedSuccessfully(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id bar { id }") {
           id: ID!
           bar: Bar!
@@ -82,7 +82,7 @@ public function testValidatesNestedSuccessfully(): void
         type Bar {
           id: ID!
         }
-        ');
+        GRAPHQL);
 
         $validator = $this->app->make(SchemaValidator::class);
         $validator->handle(new ValidateSchema($schema));
@@ -91,7 +91,7 @@ public function testValidatesNestedSuccessfully(): void
 
     public function testValidatesNestedMissingExternal(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo @key(fields: "id foo { id }") @extends {
           id: ID! @external
           bar: Bar! @external
@@ -100,7 +100,7 @@ public function testValidatesNestedMissingExternal(): void
         type Bar {
           id: ID!
         }
-        ');
+        GRAPHQL);
 
         $validator = $this->app->make(SchemaValidator::class);
         $this->expectException(FederationException::class);
diff --git a/tests/Unit/GlobalId/GlobalIdDirectiveTest.php b/tests/Unit/GlobalId/GlobalIdDirectiveTest.php
index 27f757a8f3..bc125bfabe 100644
--- a/tests/Unit/GlobalId/GlobalIdDirectiveTest.php
+++ b/tests/Unit/GlobalId/GlobalIdDirectiveTest.php
@@ -21,17 +21,17 @@ protected function setUp(): void
 
     public function testDecodesGlobalId(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: String! @globalId
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => $this->globalId->encode(RootType::QUERY, Foo::THE_ANSWER),
             ],
@@ -42,27 +42,27 @@ public function testNullableArgument(): void
     {
         $this->mockResolver(static fn ($_, array $args): ?string => $args['bar'] ?? null);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String @globalId): String @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => null,
             ],
         ]);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: null)
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => null,
             ],
@@ -73,17 +73,17 @@ public function testNullableResult(): void
     {
         $this->mockResolver();
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: String @mock @globalId
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => null,
             ],
@@ -94,7 +94,7 @@ public function testDecodesGlobalIdOnInput(): void
     {
         $this->mockResolver(static fn ($_, array $args): array => $args['input']['bar']);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: FooInput!): [String!]! @mock
         }
@@ -102,18 +102,18 @@ public function testDecodesGlobalIdOnInput(): void
         input FooInput {
             bar: String! @globalId
         }
-        ';
+        GRAPHQL;
 
         $globalId = $this->globalId->encode('foo', 'bar');
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             query ($bar: String!) {
                 foo(input: {
                     bar: $bar
                 })
             }
-            ', [
+            GRAPHQL, [
                 'bar' => $globalId,
             ])
             ->assertJson([
@@ -127,7 +127,7 @@ public function testDecodesGlobalIdInDifferentWays(): void
     {
         $this->mockResolver(static fn ($_, array $args): array => $args);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 type: ID! @globalId(decode: TYPE)
@@ -141,23 +141,23 @@ public function testDecodesGlobalIdInDifferentWays(): void
             id: ID!
             array: [String!]!
         }
-        ';
+        GRAPHQL;
 
         $globalId = $this->globalId->encode('Foo', 'bar');
 
-        $this->graphQL(/** @lang GraphQL */ "
+        $this->graphQL(/** @lang GraphQL */ <<<GRAPHQL
         {
             foo(
-                type: \"{$globalId}\"
-                id: \"{$globalId}\"
-                array: \"{$globalId}\"
+                type: "{$globalId}"
+                id: "{$globalId}"
+                array: "{$globalId}"
             ) {
                 id
                 type
                 array
             }
         }
-        ")->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'type' => 'Foo',
diff --git a/tests/Unit/Http/Middleware/AttemptAuthenticationTest.php b/tests/Unit/Http/Middleware/AttemptAuthenticationTest.php
index 6021d94e99..41aa8917cc 100644
--- a/tests/Unit/Http/Middleware/AttemptAuthenticationTest.php
+++ b/tests/Unit/Http/Middleware/AttemptAuthenticationTest.php
@@ -41,17 +41,17 @@ public function testAttemptsAuthenticationGuest(): void
                 new Callback(fn (GraphQLContext $context): bool => $this->user === null),
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testAttemptsAuthenticationUser(): void
@@ -65,16 +65,16 @@ public function testAttemptsAuthenticationUser(): void
                 new Callback(fn (GraphQLContext $context): bool => $this->user === $context->user()),
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Pagination/PaginateDirectiveTest.php b/tests/Unit/Pagination/PaginateDirectiveTest.php
index cff7144f5e..9ff5a74024 100644
--- a/tests/Unit/Pagination/PaginateDirectiveTest.php
+++ b/tests/Unit/Pagination/PaginateDirectiveTest.php
@@ -19,7 +19,7 @@ final class PaginateDirectiveTest extends TestCase
 {
     public function testIncludesPaginatorInfoTypeInSchema(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -28,10 +28,10 @@ public function testIncludesPaginatorInfoTypeInSchema(): void
         extend type Query {
             users: [User!]! @paginate
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "Information about pagination using a fully featured paginator."
         type PaginatorInfo {
           "Number of items in the current page."
@@ -63,7 +63,7 @@ public function testIncludesPaginatorInfoTypeInSchema(): void
 
     public function testIncludesSimplePaginatorInfoTypeInSchema(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -72,10 +72,10 @@ public function testIncludesSimplePaginatorInfoTypeInSchema(): void
         extend type Query {
             users: [User!]! @paginate(type: SIMPLE)
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "Information about pagination using a simple paginator."
         type SimplePaginatorInfo {
           "Number of items in the current page."
@@ -101,7 +101,7 @@ public function testIncludesSimplePaginatorInfoTypeInSchema(): void
 
     public function testIncludesPageInfoTypeInSchema(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -110,10 +110,10 @@ public function testIncludesPageInfoTypeInSchema(): void
         extend type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "Information about pagination using a Relay style cursor connection."
         type PageInfo {
           "When paginating forwards, are there more items?"
@@ -155,7 +155,7 @@ public function testDoesntIncludePaginationInfoObjectsInSchemaIfNotNeeded(): voi
 
     public function testManipulatesPaginator(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -163,7 +163,7 @@ public function testManipulatesPaginator(): void
         type Query {
             users: [User!]! @paginate
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
         $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
@@ -176,12 +176,11 @@ public function testManipulatesPaginator(): void
     page: Int
   ): UserPaginator!
 }
-GRAPHQL
-            ,
+GRAPHQL,
             $schemaString,
         );
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "A paginated list of User items."
         type UserPaginator {
           "Pagination information about the list of items."
@@ -195,7 +194,7 @@ public function testManipulatesPaginator(): void
 
     public function testManipulatesSimplePaginator(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -203,7 +202,7 @@ public function testManipulatesSimplePaginator(): void
         type Query {
             users: [User!]! @paginate(type: SIMPLE)
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
         $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
@@ -216,12 +215,11 @@ public function testManipulatesSimplePaginator(): void
     page: Int
   ): UserSimplePaginator!
 }
-GRAPHQL
-            ,
+GRAPHQL,
             $schemaString,
         );
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "A paginated list of User items."
         type UserSimplePaginator {
           "Pagination information about the list of items."
@@ -235,7 +233,7 @@ public function testManipulatesSimplePaginator(): void
 
     public function testManipulatesConnection(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -243,7 +241,7 @@ public function testManipulatesConnection(): void
         type Query {
             users: [User!]! @paginate(type: CONNECTION)
         }
-        ');
+        GRAPHQL);
         $schemaString = SchemaPrinter::doPrint($schema);
 
         $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
@@ -256,12 +254,11 @@ public function testManipulatesConnection(): void
     after: String
   ): UserConnection!
 }
-GRAPHQL
-            ,
+GRAPHQL,
             $schemaString,
         );
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "A paginated list of User edges."
         type UserConnection {
           "Pagination information about the list of edges."
@@ -272,7 +269,7 @@ public function testManipulatesConnection(): void
         }
         GRAPHQL, $schemaString);
 
-        $this->assertStringContainsString(/** @lang GraphQL */ <<<'GRAPHQL'
+        $this->assertStringContainsString(/** @lang GraphQL */ <<<GRAPHQL
         "An edge that contains a node of type User and a cursor."
         type UserEdge {
           "The User node."
@@ -294,7 +291,7 @@ public function testAliasRelayToConnection(): void
 
     protected function getConnectionQueryField(string $type): FieldDefinition
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ "
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
         type User {
             name: String
         }
@@ -302,7 +299,7 @@ protected function getConnectionQueryField(string $type): FieldDefinition
         type Query {
             users: [User!]! @paginate(type: {$type})
         }
-        ");
+        GRAPHQL);
 
         $queryType = $schema->getQueryType();
         $this->assertInstanceOf(ObjectType::class, $queryType);
@@ -312,7 +309,7 @@ protected function getConnectionQueryField(string $type): FieldDefinition
 
     public function testOnlyRegistersOneTypeForMultiplePaginators(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             name: String
             usersPaginated: [User!]! @paginate
@@ -325,7 +322,7 @@ public function testOnlyRegistersOneTypeForMultiplePaginators(): void
             usersConnection: [User!]! @paginate(type: CONNECTION)
             usersSimplePaginated: [User!]! @paginate(type: SIMPLE)
         }
-        ');
+        GRAPHQL);
         $typeMap = $schema->getTypeMap();
 
         $this->assertArrayHasKey('UserPaginator', $typeMap);
@@ -335,7 +332,7 @@ public function testOnlyRegistersOneTypeForMultiplePaginators(): void
 
     public function testRegistersPaginatorFromTypeExtensionField(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -344,7 +341,7 @@ public function testRegistersPaginatorFromTypeExtensionField(): void
         extend type Query {
             users: [User!]! @paginate
         }
-        ');
+        GRAPHQL);
         $typeMap = $schema->getTypeMap();
 
         $this->assertArrayHasKey('UserPaginator', $typeMap);
@@ -358,7 +355,7 @@ public function testHasMaxCountInGeneratedCountDescription(): void
         config(['lighthouse.pagination.max_count' => 5]);
 
         $queryType = $this
-            ->buildSchema(/** @lang GraphQL */ '
+            ->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
             type Query {
                 defaultPaginated: [User!]! @paginate
                 defaultRelay: [User!]! @paginate(type: CONNECTION)
@@ -371,7 +368,7 @@ public function testHasMaxCountInGeneratedCountDescription(): void
             type User {
                 id: ID!
             }
-            ')
+            GRAPHQL)
             ->getQueryType();
         $this->assertInstanceOf(ObjectType::class, $queryType);
 
@@ -416,7 +413,7 @@ public function testIsLimitedByMaxCountFromDirective(): void
     {
         config(['lighthouse.pagination.max_count' => 5]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -425,9 +422,9 @@ public function testIsLimitedByMaxCountFromDirective(): void
         type Query {
             users: [User!]! @paginate(maxCount: 6)
         }
-        ';
+        GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 10) {
                 data {
@@ -436,7 +433,7 @@ public function testIsLimitedByMaxCountFromDirective(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(6, 10),
@@ -459,7 +456,7 @@ public function testIsLimitedByMaxCountFromDirectiveWithResolver(): void
         }
         GRAPHQL;
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 10) {
                 data {
@@ -468,7 +465,7 @@ public function testIsLimitedByMaxCountFromDirectiveWithResolver(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(6, 10),
@@ -480,7 +477,7 @@ public function testIsLimitedToMaxCountFromConfig(): void
     {
         config(['lighthouse.pagination.max_count' => 5]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -491,9 +488,9 @@ public function testIsLimitedToMaxCountFromConfig(): void
             usersConnection: [User!]! @paginate(type: CONNECTION)
             usersSimplePaginated: [User!]! @paginate(type: SIMPLE)
         }
-        ';
+        GRAPHQL;
 
-        $resultFromDefaultPagination = $this->graphQL(/** @lang GraphQL */ '
+        $resultFromDefaultPagination = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             usersPaginated(first: 10) {
                 data {
@@ -502,14 +499,14 @@ public function testIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(5, 10),
             $resultFromDefaultPagination->json('errors.0.message'),
         );
 
-        $resultFromRelayPagination = $this->graphQL(/** @lang GraphQL */ '
+        $resultFromRelayPagination = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             usersConnection(first: 10) {
                 edges {
@@ -520,14 +517,14 @@ public function testIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(5, 10),
             $resultFromRelayPagination->json('errors.0.message'),
         );
 
-        $resultFromSimplePagination = $this->graphQL(/** @lang GraphQL */ '
+        $resultFromSimplePagination = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             usersSimplePaginated(first: 10) {
                 data {
@@ -536,7 +533,7 @@ public function testIsLimitedToMaxCountFromConfig(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $this->assertSame(
             PaginationArgs::requestedTooManyItems(5, 10),
@@ -548,7 +545,7 @@ public function testCountExplicitlyRequiredFromDirective(): void
     {
         config(['lighthouse.pagination.default_count' => 2]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -557,10 +554,10 @@ public function testCountExplicitlyRequiredFromDirective(): void
         type Query {
             users: [User!]! @paginate(defaultCount: null)
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users {
                     data {
@@ -568,13 +565,13 @@ public function testCountExplicitlyRequiredFromDirective(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage('Field "users" argument "first" of type "Int!" is required but not provided.');
     }
 
     public function testThrowsWhenPaginationWithNegativeCountIsRequested(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
             name: String!
@@ -583,10 +580,10 @@ public function testThrowsWhenPaginationWithNegativeCountIsRequested(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
         $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 users(first: -1) {
                     data {
@@ -594,21 +591,21 @@ public function testThrowsWhenPaginationWithNegativeCountIsRequested(): void
                     }
                 }
             }
-            ')
+            GRAPHQL)
             ->assertGraphQLErrorMessage(PaginationArgs::requestedLessThanZeroItems(-1));
     }
 
     public function testDoesNotRequireModelWhenUsingBuilder(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ "
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
             type Query {
-                users: [NotAnActualModelName!]! @paginate(builder: \"{$this->qualifyTestResolver('testDoesNotRequireModelWhenUsingBuilder')}\")
+                users: [NotAnActualModelName!]! @paginate(builder: "{$this->qualifyTestResolver('testDoesNotRequireModelWhenUsingBuilder')}")
             }
 
             type NotAnActualModelName {
                 id: ID!
             }
-            ");
+        GRAPHQL);
 
         $paginator = $schema->getType('NotAnActualModelNamePaginator');
         $this->assertInstanceOf(ObjectType::class, $paginator);
@@ -618,16 +615,16 @@ public function testThrowsIfBuilderIsNotPresent(): void
     {
         $this->expectExceptionObject(new DefinitionException('Failed to find class NonexistingClass in namespaces [] for directive @paginate.'));
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [Query!]! @paginate(builder: "NonexistingClass@notFound")
         }
-        ');
+        GRAPHQL);
     }
 
     public function testAllowsMultiplePaginatedFieldsOfTheSameModel(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [User!]! @paginate
             users2: [User!]! @paginate
@@ -636,7 +633,7 @@ public function testAllowsMultiplePaginatedFieldsOfTheSameModel(): void
         type User {
             id: ID
         }
-        ');
+        GRAPHQL);
 
         $userPaginator = $schema->getType('UserPaginator');
         $this->assertInstanceOf(ObjectType::class, $userPaginator);
@@ -649,7 +646,7 @@ public function testAllowsMultiplePaginatedFieldsOfTheSameModel(): void
 
     public function testDisallowFirstNull(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -657,9 +654,9 @@ public function testDisallowFirstNull(): void
         type Query {
             users: [User!]! @paginate(defaultCount: 2)
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: null) {
                 data {
@@ -667,12 +664,12 @@ public function testDisallowFirstNull(): void
                 }
             }
         }
-        ')->assertGraphQLErrorMessage('Expected value of type "Int!", found null.');
+        GRAPHQL)->assertGraphQLErrorMessage('Expected value of type "Int!", found null.');
     }
 
     public function testQueriesFirst0SimplePaginator(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             id: ID!
         }
@@ -680,9 +677,9 @@ public function testQueriesFirst0SimplePaginator(): void
         type Query {
             users: [User!]! @paginate
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 0) {
                 data {
@@ -690,7 +687,7 @@ public function testQueriesFirst0SimplePaginator(): void
                 }
             }
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'users' => [
                     'data' => [],
@@ -718,17 +715,17 @@ public static function returnPaginatedDataInsteadOfBuilder(mixed $root, array $a
 
     public function testPaginatorResolver(): void
     {
-        $this->buildSchema(/* @lang GraphQL */ "
+        $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
         type Query {
-            users: [User!]! @paginate(resolver: \"{$this->qualifyTestResolver('returnPaginatedDataInsteadOfBuilder')}\")
+            users: [User!]! @paginate(resolver: "{$this->qualifyTestResolver('returnPaginatedDataInsteadOfBuilder')}")
         }
 
         type User {
             id: ID
         }
-        ");
+        GRAPHQL);
 
-        $this->graphQL(/* @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             users(first: 5) {
                 paginatorInfo {
@@ -739,7 +736,7 @@ public function testPaginatorResolver(): void
                 }
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'users' => [
                     'paginatorInfo' => [
@@ -758,11 +755,11 @@ public function testThrowsIfResolverIsNotPresent(): void
     {
         $this->expectExceptionObject(new DefinitionException('Failed to find class NonexistingClass in namespaces [] for directive @paginate.'));
 
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             users: [Query!]! @paginate(resolver: "NonexistingClass@notFound")
         }
-        ');
+        GRAPHQL);
     }
 
     public function testCustomizeQueryComplexityResolver(): void
@@ -770,18 +767,18 @@ public function testCustomizeQueryComplexityResolver(): void
         $max = 42;
         $this->setMaxQueryComplexity($max);
 
-        $this->buildSchema(/* @lang GraphQL */ "
+        $this->buildSchema(/** @lang GraphQL */ <<<GRAPHQL
         type Query {
-            users(complexity: Int!): [User!]! @paginate(complexityResolver: \"{$this->qualifyTestResolver('complexityResolver')}\")
+            users(complexity: Int!): [User!]! @paginate(complexityResolver: "{$this->qualifyTestResolver('complexityResolver')}")
         }
 
         type User {
             id: ID
         }
-        ");
+        GRAPHQL);
 
         $complexity = 123;
-        $this->graphQL(/* @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         query ($complexity: Int!) {
             users(first: 5, complexity: $complexity) {
                 data {
@@ -789,7 +786,7 @@ public function testCustomizeQueryComplexityResolver(): void
                 }
             }
         }
-        ', [
+        GRAPHQL, [
             'complexity' => $complexity,
         ])->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, $complexity));
     }
diff --git a/tests/Unit/Schema/AST/ASTBuilderTest.php b/tests/Unit/Schema/AST/ASTBuilderTest.php
index 3938ffa655..223eaa6851 100644
--- a/tests/Unit/Schema/AST/ASTBuilderTest.php
+++ b/tests/Unit/Schema/AST/ASTBuilderTest.php
@@ -31,19 +31,19 @@ protected function setUp(): void
 
     public function testMergeTypeExtensionFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: String
-        }
-
-        extend type Query {
-            bar: Int!
-        }
-
-        extend type Query {
-            baz: Boolean
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: String
+                }
+        
+                extend type Query {
+                    bar: Int!
+                }
+        
+                extend type Query {
+                    baz: Boolean
+                }
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $queryType = $documentAST->types[RootType::QUERY];
@@ -57,22 +57,24 @@ public function testMergeTypeExtensionDirectives(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on OBJECT';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on OBJECT
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        type MyType {
-            field: String
-        }
-
-        extend type MyType @foo
-
-        extend type MyType @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type MyType {
+                    field: String
+                }
+        
+                extend type MyType @foo
+        
+                extend type MyType @foo
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myType = $documentAST->types['MyType'];
@@ -84,17 +86,17 @@ public static function definition(): string
     public function testAllowsExtendingUndefinedRootTypes(): void
     {
         $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
-        extend type Query {
-            foo: ID
-        }
-
-        extend type Mutation {
-            bar: ID
-        }
-
-        extend type Subscription {
-            baz: ID
-        }
+                extend type Query {
+                    foo: ID
+                }
+        
+                extend type Mutation {
+                    bar: ID
+                }
+        
+                extend type Subscription {
+                    baz: ID
+                }
         GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
@@ -116,19 +118,19 @@ public function testAllowsExtendingUndefinedRootTypes(): void
 
     public function testMergeInputExtensionFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        input Inputs {
-            foo: String
-        }
-
-        extend input Inputs {
-            bar: Int!
-        }
-
-        extend input Inputs {
-            baz: Boolean
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input Inputs {
+                    foo: String
+                }
+        
+                extend input Inputs {
+                    bar: Int!
+                }
+        
+                extend input Inputs {
+                    baz: Boolean
+                }
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $inputs = $documentAST->types['Inputs'];
@@ -142,22 +144,24 @@ public function testMergeInputExtensionDirectives(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on INPUT_OBJECT';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on INPUT_OBJECT
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        input MyInput {
-            field: String
-        }
-
-        extend input MyInput @foo
-
-        extend input MyInput @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input MyInput {
+                    field: String
+                }
+        
+                extend input MyInput @foo
+        
+                extend input MyInput @foo
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myInput = $documentAST->types['MyInput'];
@@ -168,19 +172,19 @@ public static function definition(): string
 
     public function testMergeInterfaceExtensionFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        interface Named {
-          name: String!
-        }
-
-        extend interface Named {
-          bar: Int!
-        }
-
-        extend interface Named {
-          baz: Boolean
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                interface Named {
+                  name: String!
+                }
+        
+                extend interface Named {
+                  bar: Int!
+                }
+        
+                extend interface Named {
+                  baz: Boolean
+                }
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $named = $documentAST->types['Named'];
@@ -194,22 +198,24 @@ public function testMergeInterfaceExtensionDirectives(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on INTERFACE';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on INTERFACE
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        interface MyInterface {
-            field: String
-        }
-
-        extend interface MyInterface @foo
-
-        extend interface MyInterface @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                interface MyInterface {
+                    field: String
+                }
+        
+                extend interface MyInterface @foo
+        
+                extend interface MyInterface @foo
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myInterface = $documentAST->types['MyInterface'];
@@ -223,20 +229,22 @@ public function testMergeScalarExtensionDirectives(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on SCALAR';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on SCALAR
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar MyScalar
-
-        extend scalar MyScalar @foo
-
-        extend scalar MyScalar @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                scalar MyScalar
+        
+                extend scalar MyScalar @foo
+        
+                extend scalar MyScalar @foo
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myScalar = $documentAST->types['MyScalar'];
@@ -247,20 +255,20 @@ public static function definition(): string
 
     public function testMergeEnumExtensionFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        enum MyEnum {
-            ONE
-            TWO
-        }
-
-        extend enum MyEnum {
-            THREE
-        }
-
-        extend enum MyEnum {
-            FOUR
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                enum MyEnum {
+                    ONE
+                    TWO
+                }
+        
+                extend enum MyEnum {
+                    THREE
+                }
+        
+                extend enum MyEnum {
+                    FOUR
+                }
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myEnum = $documentAST->types['MyEnum'];
@@ -274,23 +282,25 @@ public function testMergeEnumExtensionDirectives(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on ENUM';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on ENUM
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        enum MyEnum {
-            ONE
-            TWO
-        }
-
-        extend enum MyEnum @foo
-
-        extend enum MyEnum @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                enum MyEnum {
+                    ONE
+                    TWO
+                }
+        
+                extend enum MyEnum @foo
+        
+                extend enum MyEnum @foo
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myEnum = $documentAST->types['MyEnum'];
@@ -301,17 +311,17 @@ enum MyEnum {
 
     public function testMergeUnionExtensionFields(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-            type Foo
-            type Bar
-            type Baz
-
-            union MyUnion = Foo
-
-            extend union MyUnion = Bar
-
-            extend union MyUnion = Baz
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                    type Foo
+                    type Bar
+                    type Baz
+        
+                    union MyUnion = Foo
+        
+                    extend union MyUnion = Bar
+        
+                    extend union MyUnion = Baz
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $myUnion = $documentAST->types['MyUnion'];
@@ -325,16 +335,18 @@ public function testDoesNotAllowExtendingUndefinedScalar(): void
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo repeatable on SCALAR';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo repeatable on SCALAR
+                GRAPHQL;
             }
         };
 
         $directiveLocator = $this->app->make(DirectiveLocator::class);
         $directiveLocator->setResolved('foo', $directive::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        extend scalar MyScalar @foo
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                extend scalar MyScalar @foo
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException('Could not find a base definition MyScalar of kind ' . NodeKind::SCALAR_TYPE_EXTENSION . ' to extend.'));
         $this->astBuilder->documentAST();
@@ -342,15 +354,15 @@ public static function definition(): string
 
     public function testDoesNotAllowExtendingUndefinedTypes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: String
-        }
-
-        extend type Foo {
-            foo: Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: String
+                }
+        
+                extend type Foo {
+                    foo: Int
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException('Could not find a base definition Foo of kind ' . NodeKind::OBJECT_TYPE_EXTENSION . ' to extend.'));
         $this->astBuilder->documentAST();
@@ -358,11 +370,11 @@ public function testDoesNotAllowExtendingUndefinedTypes(): void
 
     public function testDoesNotAllowExtendingUndefinedUnions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        union MyFirstEnum = String
-
-        extend union MySecondUnion = Int
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                union MyFirstEnum = String
+        
+                extend union MySecondUnion = Int
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException('Could not find a base definition MySecondUnion of kind ' . NodeKind::UNION_TYPE_EXTENSION . ' to extend.'));
         $this->astBuilder->documentAST();
@@ -370,15 +382,15 @@ public function testDoesNotAllowExtendingUndefinedUnions(): void
 
     public function testDoesNotAllowDuplicateFieldsOnTypeExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: String
-        }
-
-        extend type Query {
-            foo: Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: String
+                }
+        
+                extend type Query {
+                    foo: Int
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(ASTHelper::duplicateDefinition('foo')));
         $this->astBuilder->documentAST();
@@ -386,15 +398,15 @@ public function testDoesNotAllowDuplicateFieldsOnTypeExtensions(): void
 
     public function testDoesNotAllowDuplicateFieldsOnInputExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        input Inputs {
-            foo: String
-        }
-
-        extend input Inputs {
-            foo: Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input Inputs {
+                    foo: String
+                }
+        
+                extend input Inputs {
+                    foo: Int
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(ASTHelper::duplicateDefinition('foo')));
         $this->astBuilder->documentAST();
@@ -402,15 +414,15 @@ public function testDoesNotAllowDuplicateFieldsOnInputExtensions(): void
 
     public function testDoesNotAllowDuplicateFieldsOnInterfaceExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        interface Named {
-            foo: String
-        }
-
-        extend interface Named{
-            foo: Int
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                interface Named {
+                    foo: String
+                }
+        
+                extend interface Named{
+                    foo: Int
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(ASTHelper::duplicateDefinition('foo')));
         $this->astBuilder->documentAST();
@@ -418,17 +430,17 @@ interface Named {
 
     public function testDoesNotAllowDuplicateValuesOnEnumExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        enum MyEnum {
-            ONE
-            TWO
-        }
-
-        extend enum MyEnum {
-            TWO
-            THREE
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                enum MyEnum {
+                    ONE
+                    TWO
+                }
+        
+                extend enum MyEnum {
+                    TWO
+                    THREE
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(ASTHelper::duplicateDefinition('TWO')));
         $this->astBuilder->documentAST();
@@ -436,14 +448,14 @@ enum MyEnum {
 
     public function testDoesNotAllowDuplicateTypesOnUnionExtensions(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Foo
-        type Bar
-
-        union MyUnion = Foo | Bar
-
-        extend union MyUnion = Bar
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Foo
+                type Bar
+        
+                union MyUnion = Foo | Bar
+        
+                extend union MyUnion = Bar
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException(ASTHelper::duplicateDefinition('Bar')));
         $this->astBuilder->documentAST();
@@ -451,15 +463,15 @@ public function testDoesNotAllowDuplicateTypesOnUnionExtensions(): void
 
     public function testDoesNotAllowMergingNonMatchingTypes(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Foo {
-            bar: ID
-        }
-
-        extend interface Foo {
-            baz: ID
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Foo {
+                    bar: ID
+                }
+        
+                extend interface Foo {
+                    baz: ID
+                }
+        GRAPHQL;
 
         $this->expectExceptionObject(new DefinitionException('The type extension Foo of kind ' . NodeKind::INTERFACE_TYPE_EXTENSION . ' can not extend a definition of kind ' . NodeKind::OBJECT_TYPE_DEFINITION . '.'));
         $this->astBuilder->documentAST();
@@ -467,23 +479,23 @@ public function testDoesNotAllowMergingNonMatchingTypes(): void
 
     public function testMergeTypeExtensionInterfaces(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type User implements Emailable {
-            email: String!
-        }
-
-        interface Emailable {
-            email: String!
-        }
-
-        interface Nameable {
-            name: String!
-        }
-
-        extend type User implements Nameable {
-            name: String!
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type User implements Emailable {
+                    email: String!
+                }
+        
+                interface Emailable {
+                    email: String!
+                }
+        
+                interface Nameable {
+                    name: String!
+                }
+        
+                extend type User implements Nameable {
+                    name: String!
+                }
+        GRAPHQL;
         $documentAST = $this->astBuilder->documentAST();
 
         $userType = $documentAST->types['User'];
diff --git a/tests/Unit/Schema/AST/ASTHelperTest.php b/tests/Unit/Schema/AST/ASTHelperTest.php
index f55cdd15a1..2498e75140 100644
--- a/tests/Unit/Schema/AST/ASTHelperTest.php
+++ b/tests/Unit/Schema/AST/ASTHelperTest.php
@@ -27,17 +27,17 @@ final class ASTHelperTest extends TestCase
 {
     public function testThrowsWhenMergingUniqueNodeListWithCollision(): void
     {
-        $objectType1 = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type User {
-            email: String
-        }
-        ');
-
-        $objectType2 = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type User {
-            email(bar: String): Int
-        }
-        ');
+        $objectType1 = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type User {
+                    email: String
+                }
+        GRAPHQL);
+
+        $objectType2 = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type User {
+                    email(bar: String): Int
+                }
+        GRAPHQL);
 
         $this->expectException(DefinitionException::class);
         ASTHelper::mergeUniqueNodeList(
@@ -48,19 +48,19 @@ public function testThrowsWhenMergingUniqueNodeListWithCollision(): void
 
     public function testMergesUniqueNodeListsWithOverwrite(): void
     {
-        $objectType1 = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type User {
-            first_name: String
-            email: String
-        }
-        ');
-
-        $objectType2 = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type User {
-            first_name: String @foo
-            last_name: String
-        }
-        ');
+        $objectType1 = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type User {
+                    first_name: String
+                    email: String
+                }
+        GRAPHQL);
+
+        $objectType2 = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type User {
+                    first_name: String @foo
+                    last_name: String
+                }
+        GRAPHQL);
 
         $objectType1->fields = ASTHelper::mergeUniqueNodeList(
             $objectType1->fields,
@@ -78,7 +78,9 @@ public function testMergesUniqueNodeListsWithOverwrite(): void
 
     public function testExtractStringArguments(): void
     {
-        $directive = Parser::constDirective(/** @lang GraphQL */ '@foo(bar: "baz")');
+        $directive = Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+        @foo(bar: "baz")
+        GRAPHQL);
         $this->assertSame(
             'baz',
             ASTHelper::directiveArgValue($directive, 'bar'),
@@ -87,7 +89,9 @@ public function testExtractStringArguments(): void
 
     public function testExtractBooleanArguments(): void
     {
-        $directive = Parser::constDirective(/** @lang GraphQL */ '@foo(bar: true)');
+        $directive = Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+        @foo(bar: true)
+        GRAPHQL);
         $this->assertTrue(
             ASTHelper::directiveArgValue($directive, 'bar'),
         );
@@ -95,7 +99,9 @@ public function testExtractBooleanArguments(): void
 
     public function testExtractArrayArguments(): void
     {
-        $directive = Parser::constDirective(/** @lang GraphQL */ '@foo(bar: ["one", "two"])');
+        $directive = Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+        @foo(bar: ["one", "two"])
+        GRAPHQL);
         $this->assertSame(
             ['one', 'two'],
             ASTHelper::directiveArgValue($directive, 'bar'),
@@ -104,7 +110,9 @@ public function testExtractArrayArguments(): void
 
     public function testExtractObjectArguments(): void
     {
-        $directive = Parser::constDirective(/** @lang GraphQL */ '@foo(bar: { baz: "foobar" })');
+        $directive = Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+        @foo(bar: { baz: "foobar" })
+        GRAPHQL);
         $this->assertSame(
             ['baz' => 'foobar'],
             ASTHelper::directiveArgValue($directive, 'bar'),
@@ -113,7 +121,9 @@ public function testExtractObjectArguments(): void
 
     public function testReturnsNullForNonExistingArgumentOnDirective(): void
     {
-        $directive = Parser::constDirective(/** @lang GraphQL */ '@foo');
+        $directive = Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+        @foo
+        GRAPHQL);
         $this->assertNull(
             ASTHelper::directiveArgValue($directive, 'bar'),
         );
@@ -121,25 +131,27 @@ public function testReturnsNullForNonExistingArgumentOnDirective(): void
 
     public function testChecksWhetherTypeImplementsInterface(): void
     {
-        $type = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type Foo implements Bar {
-            baz: String
-        }
-        ');
+        $type = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type Foo implements Bar {
+                    baz: String
+                }
+        GRAPHQL);
         $this->assertTrue(ASTHelper::typeImplementsInterface($type, 'Bar'));
         $this->assertFalse(ASTHelper::typeImplementsInterface($type, 'FakeInterface'));
     }
 
     public function testAddDirectiveToFields(): void
     {
-        $object = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type Query {
-            foo: Int
-        }
-        ');
+        $object = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: Int
+                }
+        GRAPHQL);
 
         ASTHelper::addDirectiveToFields(
-            Parser::constDirective(/** @lang GraphQL */ '@guard'),
+            Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+            @guard
+            GRAPHQL),
             $object,
         );
 
@@ -151,15 +163,17 @@ public function testAddDirectiveToFields(): void
 
     public function testPrefersFieldDirectivesOverTypeDirectives(): void
     {
-        $object = Parser::objectTypeDefinition(/** @lang GraphQL */ '
-        type Query {
-            foo: Int @complexity(resolver: "Foo")
-            bar: String
-        }
-        ');
+        $object = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: Int @complexity(resolver: "Foo")
+                    bar: String
+                }
+        GRAPHQL);
 
         ASTHelper::addDirectiveToFields(
-            Parser::constDirective(/** @lang GraphQL */ '@complexity'),
+            Parser::constDirective(/** @lang GraphQL */ <<<'GRAPHQL'
+            @complexity
+            GRAPHQL),
             $object,
         );
 
@@ -172,15 +186,17 @@ public function testPrefersFieldDirectivesOverTypeDirectives(): void
 
     public function testExtractDirectiveDefinition(): void
     {
-        $directive = ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ 'directive @foo on OBJECT');
+        $directive = ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+        directive @foo on OBJECT
+        GRAPHQL);
         $this->assertSame('foo', $directive->name->value);
     }
 
     public function testExtractDirectiveDefinitionAllowsAuxiliaryTypes(): void
     {
         $directive = ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
-        directive @foo on OBJECT
-        scalar Bar
+                directive @foo on OBJECT
+                scalar Bar
         GRAPHQL);
         $this->assertSame('foo', $directive->name->value);
     }
@@ -189,7 +205,7 @@ public function testThrowsOnSyntaxError(): void
     {
         $this->expectException(DefinitionException::class);
         ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
-        invalid GraphQL
+                invalid GraphQL
         GRAPHQL);
     }
 
@@ -197,7 +213,7 @@ public function testThrowsIfMissingDirectiveDefinitions(): void
     {
         $this->expectException(DefinitionException::class);
         ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
-        scalar Foo
+                scalar Foo
         GRAPHQL);
     }
 
@@ -205,8 +221,8 @@ public function testThrowsOnMultipleDirectiveDefinitions(): void
     {
         $this->expectException(DefinitionException::class);
         ASTHelper::extractDirectiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
-        directive @foo on OBJECT
-        directive @bar on OBJECT
+                directive @foo on OBJECT
+                directive @bar on OBJECT
         GRAPHQL);
     }
 
@@ -243,7 +259,9 @@ public function testDynamicallyAddedFieldManipulatorDirective(): void
         $directive = new class() extends BaseDirective implements FieldManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo on FIELD_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo on FIELD_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateFieldDefinition(
@@ -261,7 +279,9 @@ public function manipulateFieldDefinition(
         $dynamicDirective = new class() extends BaseDirective implements FieldManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @dynamic on FIELD_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @dynamic on FIELD_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateFieldDefinition(
@@ -278,11 +298,11 @@ public function manipulateFieldDefinition(
 
         $directiveLocator->setResolved('dynamic', $dynamicDirective::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo: String @dynamic
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo: String @dynamic
+                }
+        GRAPHQL;
         $documentAST = $astBuilder->documentAST();
 
         $queryType = $documentAST->types[RootType::QUERY];
@@ -302,7 +322,9 @@ public function testDynamicallyAddedArgManipulatorDirective(): void
         $directive = new class() extends BaseDirective implements ArgManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo on ARGUMENT_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo on ARGUMENT_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateArgDefinition(
@@ -321,7 +343,9 @@ public function manipulateArgDefinition(
         $dynamicDirective = new class() extends BaseDirective implements ArgManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @dynamic on ARGUMENT_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @dynamic on ARGUMENT_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateArgDefinition(
@@ -339,11 +363,11 @@ public function manipulateArgDefinition(
 
         $directiveLocator->setResolved('dynamic', $dynamicDirective::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        type Query {
-            foo(name: String @dynamic): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                type Query {
+                    foo(name: String @dynamic): String
+                }
+        GRAPHQL;
         $astBuilder = $this->app->make(ASTBuilder::class);
         $documentAST = $astBuilder->documentAST();
 
@@ -367,7 +391,9 @@ public function testDynamicallyAddedInputFieldManipulatorDirective(): void
         $directive = new class() extends BaseDirective implements InputFieldManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @foo on INPUT_FIELD_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @foo on INPUT_FIELD_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateInputFieldDefinition(
@@ -385,7 +411,9 @@ public function manipulateInputFieldDefinition(
         $dynamicDirective = new class() extends BaseDirective implements InputFieldManipulator {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @dynamic on INPUT_FIELD_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @dynamic on INPUT_FIELD_DEFINITION
+                GRAPHQL;
             }
 
             public function manipulateInputFieldDefinition(
@@ -402,15 +430,15 @@ public function manipulateInputFieldDefinition(
 
         $directiveLocator->setResolved('dynamic', $dynamicDirective::class);
 
-        $this->schema = /** @lang GraphQL */ '
-        input Input {
-            name: String @dynamic
-        }
-
-        type Query {
-            foo(name: Input): String
-        }
-        ';
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+                input Input {
+                    name: String @dynamic
+                }
+        
+                type Query {
+                    foo(name: Input): String
+                }
+        GRAPHQL;
         $astBuilder = $this->app->make(ASTBuilder::class);
         $documentAST = $astBuilder->documentAST();
 
diff --git a/tests/Unit/Schema/AST/DocumentASTTest.php b/tests/Unit/Schema/AST/DocumentASTTest.php
index f5ea2b6428..fd6ad27008 100644
--- a/tests/Unit/Schema/AST/DocumentASTTest.php
+++ b/tests/Unit/Schema/AST/DocumentASTTest.php
@@ -15,13 +15,13 @@ final class DocumentASTTest extends TestCase
 {
     public function testParsesSimpleSchema(): void
     {
-        $schema = /** @lang GraphQL */ '
+        $schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int
         }
-        ';
+        GRAPHQL;
         // calculated as hash('sha256', $schema)
-        $schemaHash = '99fd7bd3f58a98d8932c1f5d1da718707f6f471e93d96e0bc913436445a947ac';
+        $schemaHash = '774433c158904b98b4f69eddee3424679b99a70736960a189b7d7b5923695bac';
         $documentAST = DocumentAST::fromSource($schema);
 
         $this->assertInstanceOf(
@@ -37,7 +37,7 @@ public function testThrowsOnInvalidSchema(): void
         $this->expectException(SchemaSyntaxErrorException::class);
         $this->expectExceptionMessage('Syntax Error: Expected Name, found !, near: ');
 
-        DocumentAST::fromSource(/** @lang GraphQL */ '
+        DocumentAST::fromSource(/** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             bar: Int
         }
@@ -49,7 +49,7 @@ public function testThrowsOnInvalidSchema(): void
         type Foo {
             bar: ID
         }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsOnUnknownModelClasses(): void
@@ -57,26 +57,26 @@ public function testThrowsOnUnknownModelClasses(): void
         $this->expectException(DefinitionException::class);
         $this->expectExceptionMessage('Failed to find a model class Unknown in namespaces [Tests\Utils\Models, Tests\Utils\ModelsSecondary] referenced in @model on type Query.');
 
-        DocumentAST::fromSource(/** @lang GraphQL */ '
+        DocumentAST::fromSource(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query @model(class: "Unknown") {
             foo: Int!
         }
-        ');
+        GRAPHQL);
     }
 
     public function testOverwritesDefinitionWithSameName(): void
     {
-        $documentAST = DocumentAST::fromSource(/** @lang GraphQL */ '
+        $documentAST = DocumentAST::fromSource(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int
         }
-        ');
+        GRAPHQL);
 
-        $overwrite = Parser::objectTypeDefinition(/** @lang GraphQL */ '
+        $overwrite = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: Int
         }
-        ');
+        GRAPHQL);
 
         $documentAST->types[$overwrite->name->value] = $overwrite;
 
@@ -88,7 +88,7 @@ public function testOverwritesDefinitionWithSameName(): void
 
     public function testBeSerialized(): void
     {
-        $documentAST = DocumentAST::fromSource(/** @lang GraphQL */ '
+        $documentAST = DocumentAST::fromSource(/** @lang GraphQL */ <<<'GRAPHQL'
         extend schema @link(url: "https://specs.apollo.dev/federation/v2.3", import: ["@key"])
 
         type Query @model(class: "User") {
@@ -96,7 +96,7 @@ public function testBeSerialized(): void
         }
 
         directive @foo on FIELD
-        ');
+        GRAPHQL);
 
         $reserialized = unserialize(
             serialize($documentAST),
diff --git a/tests/Unit/Schema/DirectiveLocatorTest.php b/tests/Unit/Schema/DirectiveLocatorTest.php
index ec8ab319ac..48ac7781bc 100644
--- a/tests/Unit/Schema/DirectiveLocatorTest.php
+++ b/tests/Unit/Schema/DirectiveLocatorTest.php
@@ -34,9 +34,9 @@ public function testRegistersLighthouseDirectives(): void
 
     public function testHydratesBaseDirectives(): void
     {
-        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ '
-            foo: String @field
-        ');
+        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                    foo: String @field
+        GRAPHQL);
 
         $fieldDirective = $this
             ->directiveLocator
@@ -52,14 +52,16 @@ public function testHydratesBaseDirectives(): void
 
     public function testSkipsHydrationForNonBaseDirectives(): void
     {
-        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ '
-            foo: String @foo
-        ');
+        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                    foo: String @foo
+        GRAPHQL);
 
         $directive = new class() implements FieldMiddleware {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'foo';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                foo
+                GRAPHQL;
             }
 
             public function handleField(FieldValue $fieldValue): void {}
@@ -84,9 +86,9 @@ public function testThrowsIfDirectiveNameCanNotBeResolved(): void
 
     public function testCreateSingleDirective(): void
     {
-        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ '
-            foo: [Foo!]! @hasMany
-        ');
+        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                    foo: [Foo!]! @hasMany
+        GRAPHQL);
 
         $resolver = $this->directiveLocator->exclusiveOfType($fieldDefinition, FieldResolver::class);
         $this->assertInstanceOf(FieldResolver::class, $resolver);
@@ -97,18 +99,18 @@ public function testThrowsExceptionWhenMultipleFieldResolverDirectives(): void
         $this->expectException(DirectiveException::class);
         $this->expectExceptionMessage("Node bar can only have one directive of type Nuwave\Lighthouse\Support\Contracts\FieldResolver but found [@hasMany, @belongsTo].");
 
-        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ '
-            bar: [Bar!]! @hasMany @belongsTo
-        ');
+        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                    bar: [Bar!]! @hasMany @belongsTo
+        GRAPHQL);
 
         $this->directiveLocator->exclusiveOfType($fieldDefinition, FieldResolver::class);
     }
 
     public function testCreateMultipleDirectives(): void
     {
-        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ '
-            bar: String @can(if: ["viewBar"]) @event
-        ');
+        $fieldDefinition = Parser::fieldDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+                    bar: String @can(if: ["viewBar"]) @event
+        GRAPHQL);
 
         $middleware = $this->directiveLocator->associatedOfType($fieldDefinition, FieldMiddleware::class);
         $this->assertCount(2, $middleware);
diff --git a/tests/Unit/Schema/Directives/BaseDirectiveTest.php b/tests/Unit/Schema/Directives/BaseDirectiveTest.php
index be62be460e..c3f3ed3037 100644
--- a/tests/Unit/Schema/Directives/BaseDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/BaseDirectiveTest.php
@@ -25,11 +25,11 @@ final class BaseDirectiveTest extends TestCase
 {
     public function testGetsModelClassFromDirective(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type User @model(class: "Team") {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type User @model(class: "Team") {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: User @dummy');
 
@@ -41,11 +41,11 @@ public function testGetsModelClassFromDirective(): void
 
     public function testDefaultsToFieldTypeForTheModelClassIfObject(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type User {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type User {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: User @dummy');
 
@@ -57,11 +57,11 @@ public function testDefaultsToFieldTypeForTheModelClassIfObject(): void
 
     public function testDefaultsToFieldTypeForTheModelClassIfInterface(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        interface User {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                interface User {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: User @dummy');
 
@@ -73,17 +73,17 @@ interface User {
 
     public function testDefaultsToFieldTypeForTheModelClassIfUnion(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        union User = Admin | Member
-
-        type Admin {
-            id: ID
-        }
-
-        type Member {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                union User = Admin | Member
+        
+                type Admin {
+                    id: ID
+                }
+        
+                type Member {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: User @dummy');
 
@@ -95,9 +95,9 @@ public function testDefaultsToFieldTypeForTheModelClassIfUnion(): void
 
     public function testDoesntDefaultToFieldTypeForTheModelClassIfScalar(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        scalar User
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                scalar User
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: User @dummy');
 
@@ -125,11 +125,11 @@ public function testBuiltInTypeTolerated(): void
 
     public function testThrowsIfTheClassIsNotAModel(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type Exception {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type Exception {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: Exception @dummy');
 
@@ -139,11 +139,11 @@ public function testThrowsIfTheClassIsNotAModel(): void
 
     public function testResolvesAModelThatIsNamedLikeABaseClass(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type Closure {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type Closure {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: Closure @dummy');
 
@@ -155,11 +155,11 @@ public function testResolvesAModelThatIsNamedLikeABaseClass(): void
 
     public function testPrefersThePrimaryModelNamespace(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type Category {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type Category {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: Category @dummy');
 
@@ -171,11 +171,11 @@ public function testPrefersThePrimaryModelNamespace(): void
 
     public function testAllowsOverwritingTheDefaultModel(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type OnlyHere {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type OnlyHere {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: OnlyHere @dummy(model: "Tests\\\Utils\\\ModelsSecondary\\\Category")');
 
@@ -187,11 +187,11 @@ public function testAllowsOverwritingTheDefaultModel(): void
 
     public function testResolvesFromTheSecondaryModelNamespace(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
-        type OnlyHere {
-            id: ID
-        }
-        ';
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
+                type OnlyHere {
+                    id: ID
+                }
+        GRAPHQL;
 
         $directive = $this->constructFieldDirective('foo: OnlyHere @dummy');
 
@@ -269,7 +269,9 @@ private function constructFieldDirective(string $definition): BaseDirective
         $directive = new class() extends BaseDirective {
             public static function definition(): string
             {
-                return /** @lang GraphQL */ 'directive @base on FIELD_DEFINITION';
+                return /** @lang GraphQL */ <<<'GRAPHQL'
+                directive @base on FIELD_DEFINITION
+                GRAPHQL;
             }
 
             /**
diff --git a/tests/Unit/Schema/Directives/ComplexityDirectiveTest.php b/tests/Unit/Schema/Directives/ComplexityDirectiveTest.php
index bbae0966d0..182510ec26 100644
--- a/tests/Unit/Schema/Directives/ComplexityDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/ComplexityDirectiveTest.php
@@ -26,7 +26,7 @@ public function testDefaultComplexity(): void
         $max = 1;
         $this->setMaxQueryComplexity($max);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts: [Post!]! @all
         }
@@ -34,15 +34,15 @@ public function testDefaultComplexity(): void
         type Post {
             title: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts {
                 title
             }
         }
-        ')->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, 2));
+        GRAPHQL)->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, 2));
 
         $this->assertCount(1, $events);
 
@@ -58,7 +58,7 @@ public function testKnowsPagination(): void
         $max = 1;
         $this->setMaxQueryComplexity($max);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts: [Post!]! @paginate
         }
@@ -66,12 +66,12 @@ public function testKnowsPagination(): void
         type Post {
             title: String
         }
-        ';
+        GRAPHQL;
 
         // 1 + (2 for data & title * 10 first items)
         $expectedCount = 21;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(first: 10) {
                 data {
@@ -79,7 +79,7 @@ public function testKnowsPagination(): void
                 }
             }
         }
-        ')->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, $expectedCount));
+        GRAPHQL)->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, $expectedCount));
     }
 
     public function testIgnoresFirstArgumentUnrelatedToPagination(): void
@@ -87,7 +87,7 @@ public function testIgnoresFirstArgumentUnrelatedToPagination(): void
         $max = 1;
         $this->setMaxQueryComplexity($max);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             posts(first: String!): [Post!]! @all
         }
@@ -95,15 +95,15 @@ public function testIgnoresFirstArgumentUnrelatedToPagination(): void
         type Post {
             title: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             posts(first: "named like the generated argument of @paginate, but should not increase complexity here") {
                 title
             }
         }
-        ')->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, 2));
+        GRAPHQL)->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, 2));
     }
 
     public function testCustomComplexityResolver(): void
@@ -117,11 +117,11 @@ public function testCustomComplexityResolver(): void
         }
 GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, self::CUSTOM_COMPLEXITY));
+        GRAPHQL)->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, self::CUSTOM_COMPLEXITY));
     }
 
     public function testResolvesComplexityResolverThroughDefaultNamespace(): void
@@ -135,11 +135,11 @@ public function testResolvesComplexityResolverThroughDefaultNamespace(): void
         }
         GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, Foo::THE_ANSWER));
+        GRAPHQL)->assertGraphQLErrorMessage(QueryComplexity::maxQueryComplexityErrorMessage($max, Foo::THE_ANSWER));
     }
 
     public static function complexity(): int
diff --git a/tests/Unit/Schema/Directives/DeprecatedDirectiveTest.php b/tests/Unit/Schema/Directives/DeprecatedDirectiveTest.php
index afb6c58884..a99ff5f838 100644
--- a/tests/Unit/Schema/Directives/DeprecatedDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/DeprecatedDirectiveTest.php
@@ -11,10 +11,10 @@ final class DeprecatedDirectiveTest extends TestCase
     public function testRemoveDeprecatedFieldsFromIntrospection(): void
     {
         $reason = 'Use `bar` field';
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type Query {
             withReason: String @mock
-                @deprecated(reason: \"{$reason}\")
+                @deprecated(reason: "{$reason}")
             withDefaultReason: String @mock
                 @deprecated
             notDeprecated: String @mock
@@ -24,9 +24,9 @@ enum Foo {
             DEPRECATED @deprecated
             NOT_DEPRECATED
         }
-        ";
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         query ($includeDeprecated: Boolean!) {
             __schema {
                 queryType {
@@ -46,7 +46,7 @@ enumValues(includeDeprecated: $includeDeprecated) {
                 }
             }
         }
-        ';
+        GRAPHQL;
         $withoutDeprecatedIntrospection = $this->graphQL(
             $introspectionQuery,
             [
diff --git a/tests/Unit/Schema/Directives/DropDirectiveTest.php b/tests/Unit/Schema/Directives/DropDirectiveTest.php
index 820d90117a..85cd2b5b57 100644
--- a/tests/Unit/Schema/Directives/DropDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/DropDirectiveTest.php
@@ -16,20 +16,20 @@ public function testDropArgument(): void
                 ],
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 baz: String @drop
                 bar: String
             ): Boolean @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(baz: "something", bar: "something")
         }
-        ');
+        GRAPHQL);
     }
 
     public function testDropListOfInputs(): void
@@ -44,7 +44,7 @@ public function testDropListOfInputs(): void
                 ],
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 input: [FooInput]
@@ -55,9 +55,9 @@ public function testDropListOfInputs(): void
             baz: String @drop
             bar: String
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(
                 input: [
@@ -68,6 +68,6 @@ public function testDropListOfInputs(): void
                 ]
             )
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Directives/FieldDirectiveTest.php b/tests/Unit/Schema/Directives/FieldDirectiveTest.php
index 882faba248..5e3a57c667 100644
--- a/tests/Unit/Schema/Directives/FieldDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/FieldDirectiveTest.php
@@ -11,17 +11,17 @@ final class FieldDirectiveTest extends TestCase
 {
     public function testAssignsResolverFromCombinedDefinition(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
-            bar: String! @field(resolver:"Tests\\\Utils\\\Resolvers\\\Foo@bar")
+            bar: String! @field(resolver:"Tests\\Utils\\Resolvers\\Foo@bar")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             bar
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'bar' => 'foo.bar',
             ],
@@ -30,17 +30,17 @@ public function testAssignsResolverFromCombinedDefinition(): void
 
     public function testAssignsResolverWithInvokableClass(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
-            baz: String! @field(resolver:"Tests\\\Utils\\\Resolvers\\\Foo")
+            baz: String! @field(resolver:"Tests\\Utils\\Resolvers\\Foo")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             baz
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'baz' => 'foo.baz',
             ],
@@ -49,17 +49,17 @@ public function testAssignsResolverWithInvokableClass(): void
 
     public function testUsesDefaultFieldNamespace(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             baz: String! @field(resolver: "FooBar")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             baz
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'baz' => FooBar::INVOKE_RESULT,
             ],
@@ -70,7 +70,7 @@ public function testUsesNonRootParentNamespace(): void
     {
         $this->mockResolver([]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @mock
         }
@@ -78,15 +78,15 @@ public function testUsesNonRootParentNamespace(): void
         type User {
             foo: String! @field(resolver: "NonRootClassResolver")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 foo
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'user' => [
                     'foo' => NonRootClassResolver::RESULT,
@@ -97,17 +97,17 @@ public function testUsesNonRootParentNamespace(): void
 
     public function testUsesDefaultFieldNamespaceWithCustomMethodName(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: String! @field(resolver: "FooBar@customResolve")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             bar
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'bar' => FooBar::CUSTOM_RESOLVE_RESULT,
             ],
@@ -116,35 +116,35 @@ public function testUsesDefaultFieldNamespaceWithCustomMethodName(): void
 
     public function testThrowsAnErrorWhenNoClassFound(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: String! @field(resolver: "NonExisting")
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
         $this->expectExceptionMessage('Failed to find class NonExisting in namespaces [Tests\Utils\Queries, Tests\Utils\QueriesSecondary] for directive @field.');
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testThrowsAnErrorWhenClassIsNotInvokable(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             bar: String! @field(resolver: "MissingInvoke")
         }
-        ';
+        GRAPHQL;
 
         $this->expectException(DefinitionException::class);
         $this->expectExceptionMessage("Method '__invoke' does not exist on class 'Tests\Utils\Queries\MissingInvoke'.");
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             bar
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Directives/HasManyDirectiveTest.php b/tests/Unit/Schema/Directives/HasManyDirectiveTest.php
index 6688eae8b4..1a6bfbc108 100644
--- a/tests/Unit/Schema/Directives/HasManyDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/HasManyDirectiveTest.php
@@ -10,7 +10,7 @@ final class HasManyDirectiveTest extends DBTestCase
 {
     public function testUsesEdgeTypeForRelayConnections(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks: [Task!]! @hasMany (
                 type: CONNECTION
@@ -31,7 +31,7 @@ public function testUsesEdgeTypeForRelayConnections(): void
         type Query {
             user: User @auth
         }
-        ';
+        GRAPHQL;
 
         $expectedConnectionName = 'TaskEdgeConnection';
 
@@ -57,7 +57,7 @@ public function testThrowsErrorWithUnknownTypeArg(): void
     {
         $this->expectExceptionObject(new DefinitionException('Found invalid pagination type: foo'));
 
-        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             tasks(first: Int! after: Int): [Task!]! @hasMany(type: "foo")
         }
@@ -65,6 +65,6 @@ public function testThrowsErrorWithUnknownTypeArg(): void
         type Task {
             foo: String
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Directives/HashDirectiveTest.php b/tests/Unit/Schema/Directives/HashDirectiveTest.php
index b29e46ce5c..2c1b1a7359 100644
--- a/tests/Unit/Schema/Directives/HashDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/HashDirectiveTest.php
@@ -8,7 +8,7 @@ final class HashDirectiveTest extends TestCase
 {
     public function testHashAnArgument(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: String! @hash): Foo @mock
         }
@@ -16,18 +16,18 @@ public function testHashAnArgument(): void
         type Foo {
             bar: String!
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): array => $args);
 
         $password = $this
-            ->graphQL(/** @lang GraphQL */ '
+            ->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
             {
                 foo(bar: "password") {
                     bar
                 }
             }
-            ')
+            GRAPHQL)
             ->json('data.foo.bar');
 
         $this->assertNotSame('password', $password);
@@ -36,7 +36,7 @@ public function testHashAnArgument(): void
 
     public function testHashAnArgumentInInputObjectAndArray(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(input: UserInput!): User @mock
         }
@@ -52,11 +52,11 @@ public function testHashAnArgumentInInputObjectAndArray(): void
             alt_passwords: [String!] @hash
             friends: [UserInput!]
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): array => $args['input']);
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(input: {
                 password: "password"
@@ -82,7 +82,7 @@ public function testHashAnArgumentInInputObjectAndArray(): void
                 }
             }
         }
-        ');
+        GRAPHQL);
 
         $password = $result->json('data.user.password');
         $this->assertNotSame('password', $password);
@@ -117,7 +117,7 @@ public function testHashAnArgumentInInputObjectAndArray(): void
 
     public function testHashWithRename(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user(input: UserInput!): User @mock
         }
@@ -129,11 +129,11 @@ public function testHashWithRename(): void
         input UserInput {
             password: String! @hash @rename(attribute: "password_renamed")
         }
-        ';
+        GRAPHQL;
 
         $this->mockResolver(static fn ($_, array $args): array => $args['input']);
 
-        $result = $this->graphQL(/** @lang GraphQL */ '
+        $result = $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user(input: {
                 password: "password"
@@ -141,7 +141,7 @@ public function testHashWithRename(): void
                 password_renamed
             }
         }
-        ');
+        GRAPHQL);
 
         $password = $result->json('data.user.password_renamed');
         $this->assertNotSame('password', $password);
diff --git a/tests/Unit/Schema/Directives/HideDirectiveTest.php b/tests/Unit/Schema/Directives/HideDirectiveTest.php
index 1602779572..0ad5888bbe 100644
--- a/tests/Unit/Schema/Directives/HideDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/HideDirectiveTest.php
@@ -9,14 +9,14 @@ final class HideDirectiveTest extends TestCase
 {
     public function testHiddenOnTestingEnv(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             shownField: String! @mock
             hiddenField: String! @mock @hide(env: ["testing"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -26,29 +26,29 @@ public function testHiddenOnTestingEnv(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($introspectionQuery)
             ->assertJsonPath('data.__schema.queryType.fields.*.name', ['shownField']);
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             hiddenField
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($query)->assertGraphQLErrorMessage('Cannot query field "hiddenField" on type "Query". Did you mean "shownField"?');
     }
 
     public function testHiddenArgs(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             field(hiddenArg: String @hide(env: ["testing"])): String! @mock
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -60,7 +60,7 @@ public function testHiddenArgs(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($introspectionQuery)
             ->assertJsonCount(0, 'data.__schema.queryType.fields.0.args');
@@ -68,16 +68,16 @@ public function testHiddenArgs(): void
 
     public function testHiddenType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             field: String! @mock
         }
         type HiddenType @hide(env: ["testing"]) {
             field: String!
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 types {
@@ -85,7 +85,7 @@ public function testHiddenType(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $types = $this->graphQL($introspectionQuery)
             ->json('data.__schema.types.*.name');
@@ -95,7 +95,7 @@ public function testHiddenType(): void
 
     public function testHiddenInputField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             field: String! @mock
         }
@@ -103,9 +103,9 @@ public function testHiddenInputField(): void
         input Input {
             hiddenInputField: String! @hide(env: ["testing"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 types {
@@ -116,7 +116,7 @@ public function testHiddenInputField(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $types = $this->graphQL($introspectionQuery)
             ->json('data.__schema.types');
@@ -129,13 +129,13 @@ public function testHiddenInputField(): void
 
     public function testHiddenWhenManuallySettingEnv(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             hiddenField: String! @mock @hide(env: ["production"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -145,7 +145,7 @@ public function testHiddenWhenManuallySettingEnv(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         Container::getInstance()->instance('env', 'production');
         $this->graphQL($introspectionQuery)
@@ -154,13 +154,13 @@ public function testHiddenWhenManuallySettingEnv(): void
 
     public function testShownOnAnotherEnv(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             hiddenField: String! @mock @hide(env: ["production"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -170,7 +170,7 @@ public function testShownOnAnotherEnv(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($introspectionQuery)
             ->assertJsonCount(1, 'data.__schema.queryType.fields')
diff --git a/tests/Unit/Schema/Directives/MethodDirectiveTest.php b/tests/Unit/Schema/Directives/MethodDirectiveTest.php
index 7e7bac7fb8..46032feb59 100644
--- a/tests/Unit/Schema/Directives/MethodDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/MethodDirectiveTest.php
@@ -8,72 +8,72 @@
 
 final class MethodDirectiveTest extends TestCase
 {
-    protected string $schema = /** @lang GraphQL */ '
+    protected string $schema = /** @lang GraphQL */ <<<'GRAPHQL'
     type Query {
         foo: Foo @mock
     }
-    ';
+    GRAPHQL;
 
     public function testDefaultToFieldNameAsMethodName(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar: ID @method
         }
-        ';
+        GRAPHQL;
 
         $foo = $this->mockFoo();
         $foo->expects($this->once())
             ->method('bar')
             ->with();
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 bar
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testWillPreferExplicitName(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             asdf: ID @method(name: "bar")
         }
-        ';
+        GRAPHQL;
 
         $foo = $this->mockFoo();
         $foo->expects($this->once())
             ->method('bar');
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 asdf
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testPassArgsInLexicalOrderOfDefinition(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar(
                 first: ID
                 second: ID
             ): ID @method
         }
-        ';
+        GRAPHQL;
 
         $foo = $this->mockFoo();
         $foo->expects($this->once())
             ->method('bar')
             ->with(1, 2);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 bar(
@@ -82,31 +82,31 @@ public function testPassArgsInLexicalOrderOfDefinition(): void
                 )
             }
         }
-        ');
+        GRAPHQL);
     }
 
     public function testPassOrderedDefaultsToNull(): void
     {
-        $this->schema .= /** @lang GraphQL */ '
+        $this->schema .= /** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar(
                 baz: ID
             ): ID @method
         }
-        ';
+        GRAPHQL;
 
         $foo = $this->mockFoo();
         $foo->expects($this->once())
             ->method('bar')
             ->with(null);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 bar
             }
         }
-        ');
+        GRAPHQL);
     }
 
     private function mockFoo(): MockObject
diff --git a/tests/Unit/Schema/Directives/NamespaceDirectiveTest.php b/tests/Unit/Schema/Directives/NamespaceDirectiveTest.php
index accaae80ca..6ce3161c91 100644
--- a/tests/Unit/Schema/Directives/NamespaceDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/NamespaceDirectiveTest.php
@@ -9,19 +9,19 @@ final class NamespaceDirectiveTest extends TestCase
 {
     public function testSetNamespaceOnField(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: String
                 @field(resolver: "Foo")
-                @namespace(field: "Tests\\\Utils\\\QueriesSecondary")
+                @namespace(field: "Tests\\Utils\\QueriesSecondary")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::NOT_THE_ANSWER,
             ],
@@ -30,17 +30,17 @@ public function testSetNamespaceOnField(): void
 
     public function testSetNamespaceFromType(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query @namespace(field: "Tests\\\Utils\\\QueriesSecondary") {
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        type Query @namespace(field: "Tests\\Utils\\QueriesSecondary") {
             foo: String @field(resolver: "Foo")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::NOT_THE_ANSWER,
             ],
@@ -49,19 +49,19 @@ public function testSetNamespaceFromType(): void
 
     public function testPrefersFieldNamespaceOverTypeNamespace(): void
     {
-        $this->schema = /** @lang GraphQL */ '
-        type Query @namespace(field: "Tests\\\Utils\\\QueriesSecondary") {
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        type Query @namespace(field: "Tests\\Utils\\QueriesSecondary") {
             foo: Int
                 @field(resolver: "Foo")
-                @namespace(field: "Tests\\\Utils\\\Queries")
+                @namespace(field: "Tests\\Utils\\Queries")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => \Tests\Utils\Queries\Foo::THE_ANSWER,
             ],
diff --git a/tests/Unit/Schema/Directives/RenameDirectiveTest.php b/tests/Unit/Schema/Directives/RenameDirectiveTest.php
index 53dfa19bce..12efb3bcaf 100644
--- a/tests/Unit/Schema/Directives/RenameDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/RenameDirectiveTest.php
@@ -13,7 +13,7 @@ public function testRenameField(): void
             'baz' => 'asdf',
         ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Foo @mock
         }
@@ -21,15 +21,15 @@ public function testRenameField(): void
         type Foo {
             bar: String! @rename(attribute: "baz")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo {
                 bar
             }
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => [
                     'bar' => 'asdf',
@@ -42,17 +42,17 @@ public function testThrowsAnExceptionIfNoAttributeDefined(): void
     {
         $this->expectException(DefinitionException::class);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: String! @rename
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testRenameArgument(): void
@@ -63,19 +63,19 @@ public function testRenameArgument(): void
                 ['bar' => 'something'],
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 baz: String @rename(attribute: "bar")
             ): Boolean @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(baz: "something")
         }
-        ');
+        GRAPHQL);
     }
 
     public function testRenameListOfInputs(): void
@@ -90,7 +90,7 @@ public function testRenameListOfInputs(): void
                 ],
             );
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 input: [FooInput]
@@ -100,9 +100,9 @@ public function testRenameListOfInputs(): void
         input FooInput {
             baz: String @rename(attribute: "bar")
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(
                 input: [
@@ -112,6 +112,6 @@ public function testRenameListOfInputs(): void
                 ]
             )
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Directives/ShowDirectiveTest.php b/tests/Unit/Schema/Directives/ShowDirectiveTest.php
index 8840366e2f..599ee13915 100644
--- a/tests/Unit/Schema/Directives/ShowDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/ShowDirectiveTest.php
@@ -9,14 +9,14 @@ final class ShowDirectiveTest extends TestCase
 {
     public function testHiddenOnTestingEnv(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             shownField: String! @mock
             hiddenField: String! @mock @show(env: ["production"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -26,29 +26,29 @@ public function testHiddenOnTestingEnv(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($introspectionQuery)
             ->assertJsonPath('data.__schema.queryType.fields.*.name', ['shownField']);
 
-        $query = /** @lang GraphQL */ '
+        $query = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             hiddenField
         }
-        ';
+        GRAPHQL;
 
         $this->graphQL($query)->assertGraphQLErrorMessage('Cannot query field "hiddenField" on type "Query". Did you mean "shownField"?');
     }
 
     public function testShownOnAnotherEnv(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             hiddenField: String! @mock @show(env: ["production"])
         }
-        ';
+        GRAPHQL;
 
-        $introspectionQuery = /** @lang GraphQL */ '
+        $introspectionQuery = /** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -58,7 +58,7 @@ public function testShownOnAnotherEnv(): void
                 }
             }
         }
-        ';
+        GRAPHQL;
 
         Container::getInstance()->instance('env', 'production');
         $this->graphQL($introspectionQuery)
diff --git a/tests/Unit/Schema/Directives/SpreadDirectiveTest.php b/tests/Unit/Schema/Directives/SpreadDirectiveTest.php
index e3159c79e4..ebbd6917c0 100644
--- a/tests/Unit/Schema/Directives/SpreadDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/SpreadDirectiveTest.php
@@ -14,7 +14,7 @@ public function testSpread(): void
                 'foo' => 1,
             ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Foo @spread): Int @mock
         }
@@ -22,15 +22,15 @@ public function testSpread(): void
         input Foo {
             foo: Int
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 foo: 1
             })
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNestedSpread(): void
@@ -41,7 +41,7 @@ public function testNestedSpread(): void
                 'baz' => 2,
             ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: Foo @spread): Int @mock
         }
@@ -54,9 +54,9 @@ public function testNestedSpread(): void
         input Bar {
             baz: Int
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: {
                 foo: 1
@@ -65,7 +65,7 @@ public function testNestedSpread(): void
                 }
             })
         }
-        ');
+        GRAPHQL);
     }
 
     public function testNestedSpreadInList(): void
@@ -79,7 +79,7 @@ public function testNestedSpreadInList(): void
                 ],
             ]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: [Foo!]!): Int @mock
         }
@@ -91,9 +91,9 @@ public function testNestedSpreadInList(): void
         input Bar {
             baz: Int!
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(input: [
                 {
@@ -103,13 +103,13 @@ public function testNestedSpreadInList(): void
                 }
             ])
         }
-        ');
+        GRAPHQL);
     }
 
     public function testSpreadOnListThrows(): void
     {
         $this->expectExceptionObject(new DefinitionException('Cannot use @spread on argument Query.foo:input with a list type.'));
-        $this->buildSchema(/** @lang GraphQL */ '
+        $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(input: [Foo!]! @spread): Int
         }
@@ -117,6 +117,6 @@ public function testSpreadOnListThrows(): void
         input Foo {
             bar: Int!
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Directives/ThrottleDirectiveTest.php b/tests/Unit/Schema/Directives/ThrottleDirectiveTest.php
index adda90a255..e7a80ac672 100644
--- a/tests/Unit/Schema/Directives/ThrottleDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/ThrottleDirectiveTest.php
@@ -15,11 +15,11 @@ final class ThrottleDirectiveTest extends TestCase
 {
     public function testNamedLimiter(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
         $queriedKeys = [];
 
@@ -46,11 +46,11 @@ public function testNamedLimiter(): void
 
         $this->app->singleton(RateLimiter::class, static fn (): RateLimiter => $rateLimiter);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -62,11 +62,11 @@ public function testNamedLimiter(): void
 
     public function testUnlimitedNamedLimiter(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
         $rateLimiter = $this->createMock(RateLimiter::class);
         $rateLimiter->expects($this->atLeast(1))
@@ -82,11 +82,11 @@ public function testUnlimitedNamedLimiter(): void
 
         $this->app->singleton(RateLimiter::class, static fn (): RateLimiter => $rateLimiter);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
@@ -95,11 +95,11 @@ public function testUnlimitedNamedLimiter(): void
 
     public function testWithNullRequest(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: Int @throttle(name: "test")
         }
-        ';
+        GRAPHQL;
 
         $rateLimiter = $this->createMock(RateLimiter::class);
         $rateLimiter->expects($this->atLeast(1))
@@ -122,11 +122,11 @@ public function generate(?Request $request): GraphQLContext
 
         $this->app->singleton(RateLimiter::class, static fn (): RateLimiter => $rateLimiter);
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertJson([
+        GRAPHQL)->assertJson([
             'data' => [
                 'foo' => Foo::THE_ANSWER,
             ],
diff --git a/tests/Unit/Schema/Directives/UploadDirectiveTest.php b/tests/Unit/Schema/Directives/UploadDirectiveTest.php
index bbd25986e6..0c586d4d1e 100644
--- a/tests/Unit/Schema/Directives/UploadDirectiveTest.php
+++ b/tests/Unit/Schema/Directives/UploadDirectiveTest.php
@@ -21,25 +21,25 @@ public function testUploadArgumentWithDefaultParameters(): void
 
         Storage::fake('uploadDisk');
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload
             ): String @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = UploadedFile::fake()->create('test.pdf', 500);
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                     mutation ($file: Upload!) {
                         file: upload(file: $file)
                     }
-                ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -64,25 +64,25 @@ public function testUploadArgumentWithDiskParameter(): void
             return $filePath = $args['file'];
         });
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload(disk:"uploadDisk")
             ): String @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = UploadedFile::fake()->create('test.pdf', 500);
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -106,25 +106,25 @@ public function testUploadArgumentWithPathParameter(): void
             return $filePath = $args['file'];
         });
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload(path:"test")
             ): String @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = UploadedFile::fake()->create('test.pdf', 500);
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -148,25 +148,25 @@ public function testUploadArgumentWithPublicParameter(): void
             return $filePath = $args['file'];
         });
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload(public: true disk:"uploadDisk")
             ): String @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = UploadedFile::fake()->create('test.pdf', 500);
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -189,23 +189,23 @@ public function testUploadArgumentWhereValueIsNull(): void
             return $filePath = $args['file'];
         });
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload @upload
             ): String @mock
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -223,15 +223,15 @@ public function testThrowsAnExceptionIfDiskIsMissing(): void
     {
         config(['filesystems.default' => 'uploadDisk']);
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload(disk:"uploadDisk")
             ): Boolean
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = UploadedFile::fake()->create('test.pdf', 500);
 
@@ -239,11 +239,11 @@ public function testThrowsAnExceptionIfDiskIsMissing(): void
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -258,15 +258,15 @@ public function testThrowsAnExceptionIfStoringFails(): void
         config(['filesystems.default' => 'uploadDisk']);
         Storage::fake('uploadDisk');
 
-        $this->schema = /** @lang GraphQL */ '
-        scalar Upload @scalar(class: "Nuwave\\\\Lighthouse\\\\Schema\\\\Types\\\\Scalars\\\\Upload")
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
+        scalar Upload @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\Upload")
 
         type Mutation {
             upload(
             file: Upload! @upload(path:"/")
             ): String
         }
-        ' . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $file = \Mockery::mock(File::class);
 
@@ -280,11 +280,11 @@ public function testThrowsAnExceptionIfStoringFails(): void
 
         $this->multipartGraphQL(
             [
-                'query' => /** @lang GraphQL */ '
+                'query' => /** @lang GraphQL */ <<<'GRAPHQL'
                 mutation ($file: Upload!) {
                     file: upload(file: $file)
                 }
-            ',
+                GRAPHQL,
                 'variables' => [
                     'file' => null,
                 ],
@@ -296,19 +296,19 @@ public function testThrowsAnExceptionIfStoringFails(): void
 
     public function testThrowsAnExceptionIfAttributeIsNotUploadedFile(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 baz: String @upload
             ): Boolean
         }
-        ';
+        GRAPHQL;
 
         $this->expectExceptionObject(new \InvalidArgumentException('Expected argument `baz` to be instanceof Illuminate\\Http\\UploadedFile.'));
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(baz: "something")
         }
-        ');
+        GRAPHQL);
     }
 }
diff --git a/tests/Unit/Schema/Factories/DirectiveFactoryTest.php b/tests/Unit/Schema/Factories/DirectiveFactoryTest.php
index 23fd75e111..f6d3846045 100644
--- a/tests/Unit/Schema/Factories/DirectiveFactoryTest.php
+++ b/tests/Unit/Schema/Factories/DirectiveFactoryTest.php
@@ -26,7 +26,7 @@ protected function setUp(): void
 
     public function testConvertDirectiveFromNodeToExecutable(): void
     {
-        $node = Parser::directiveDefinition(/** @lang GraphQL */ '
+        $node = Parser::directiveDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         "foo description"
         directive @foo(
             """
@@ -35,7 +35,7 @@ public function testConvertDirectiveFromNodeToExecutable(): void
             """
             baz: Int
         ) repeatable on OBJECT
-        ');
+        GRAPHQL);
         $executable = $this->directiveFactory->handle($node);
 
         $this->assertSame('foo description', $executable->description);
diff --git a/tests/Unit/Schema/ResolverProviderTest.php b/tests/Unit/Schema/ResolverProviderTest.php
index 22b71d89e7..10382df494 100644
--- a/tests/Unit/Schema/ResolverProviderTest.php
+++ b/tests/Unit/Schema/ResolverProviderTest.php
@@ -55,11 +55,11 @@ public function testThrowsIfRootFieldHasNoResolver(): void
 
     private function constructFieldValue(string $fieldDefinition, string $parentTypeName = RootType::QUERY): FieldValue
     {
-        $queryType = Parser::objectTypeDefinition(/** @lang GraphQL */ "
+        $queryType = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<GRAPHQL
         type {$parentTypeName} {
             {$fieldDefinition}
         }
-        ");
+        GRAPHQL);
 
         $typeValue = new TypeValue($queryType);
 
diff --git a/tests/Unit/Schema/SchemaBuilderTest.php b/tests/Unit/Schema/SchemaBuilderTest.php
index 4aa6a78f4b..a9962c8a56 100644
--- a/tests/Unit/Schema/SchemaBuilderTest.php
+++ b/tests/Unit/Schema/SchemaBuilderTest.php
@@ -26,13 +26,13 @@ public function testGeneratesValidSchema(): void
     public function testGeneratesWithEmptyQueryType(): void
     {
         $this
-            ->buildSchema(/** @lang GraphQL */ '
+            ->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
             type Query
 
             extend type Query {
                 foo: Int
             }
-            ')
+            GRAPHQL)
             ->assertValid();
 
         $this->expectNotToPerformAssertions();
@@ -40,7 +40,7 @@ public function testGeneratesWithEmptyQueryType(): void
 
     public function testGeneratesWithEmptyMutationType(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query
 
         type Mutation
@@ -48,7 +48,7 @@ public function testGeneratesWithEmptyMutationType(): void
         extend type Mutation {
             foo(bar: String! baz: String): String
         }
-        ');
+        GRAPHQL);
 
         $mutationObjectType = $schema->getType(RootType::MUTATION);
         $this->assertInstanceOf(ObjectType::class, $mutationObjectType);
@@ -58,7 +58,7 @@ public function testGeneratesWithEmptyMutationType(): void
 
     public function testResolveEnumTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         "Role description"
         enum Role {
             "Company administrator."
@@ -67,7 +67,7 @@ enum Role {
             "Company employee."
             EMPLOYEE @enum(value: "employee")
         }
-        ');
+        GRAPHQL);
 
         $enumType = $schema->getType('Role');
         $this->assertInstanceOf(EnumType::class, $enumType);
@@ -83,7 +83,7 @@ enum Role {
 
     public function testResolveInterfaceTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         """
         int
         """
@@ -91,7 +91,7 @@ interface Foo {
             "bar is baz"
             bar: String!
         }
-        ');
+        GRAPHQL);
 
         $interfaceType = $schema->getType('Foo');
         $this->assertInstanceOf(InterfaceType::class, $interfaceType);
@@ -102,7 +102,7 @@ interface Foo {
 
     public function testResolveObjectTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         "asdf"
         type Foo {
             "bar attribute of Foo"
@@ -111,7 +111,7 @@ public function testResolveObjectTypes(): void
                 baz: Boolean = false
             ): String!
         }
-        ');
+        GRAPHQL);
 
         $foo = $schema->getType('Foo');
         $this->assertInstanceOf(ObjectType::class, $foo);
@@ -129,14 +129,14 @@ public function testResolveObjectTypes(): void
 
     public function testResolveInputObjectTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         "bla"
         input CreateFoo {
             "xyz"
             foo: String!
             bar: Int = 123
         }
-        ');
+        GRAPHQL);
 
         $inputObjectType = $schema->getType('CreateFoo');
         $this->assertInstanceOf(InputObjectType::class, $inputObjectType);
@@ -149,11 +149,11 @@ public function testResolveInputObjectTypes(): void
 
     public function testResolveMutations(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Mutation {
             foo(bar: String! baz: String): String
         }
-        ');
+        GRAPHQL);
 
         $mutationObjectType = $schema->getType(RootType::MUTATION);
         $this->assertInstanceOf(ObjectType::class, $mutationObjectType);
@@ -173,7 +173,7 @@ public function testResolveQueries(): void
 
     public function testExtendObjectTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             bar: String!
         }
@@ -181,7 +181,7 @@ public function testExtendObjectTypes(): void
         extend type Foo {
             baz: String!
         }
-        ');
+        GRAPHQL);
 
         $objectType = $schema->getType('Foo');
         $this->assertInstanceOf(ObjectType::class, $objectType);
@@ -192,7 +192,7 @@ public function testExtendObjectTypes(): void
 
     public function testExtendTypes(): void
     {
-        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ <<<'GRAPHQL'
         type Foo {
             foo: String!
         }
@@ -201,7 +201,7 @@ public function testExtendTypes(): void
             "yo?"
             bar: String!
         }
-        ');
+        GRAPHQL);
 
         $type = $schema->getType('Foo');
         $this->assertInstanceOf(ObjectType::class, $type);
@@ -211,7 +211,7 @@ public function testExtendTypes(): void
 
     public function testResolvesEnumDefaultValuesToInternalValues(): void
     {
-        $schema = $this->buildSchema(/** @lang GraphQL */ '
+        $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(
                 bar: Baz = FOOBAR
@@ -221,7 +221,7 @@ public function testResolvesEnumDefaultValuesToInternalValues(): void
         enum Baz {
             FOOBAR @enum(value: "internal")
         }
-        ');
+        GRAPHQL);
 
         $queryType = $schema->getQueryType();
         $this->assertInstanceOf(ObjectType::class, $queryType);
diff --git a/tests/Unit/Schema/SecurityTest.php b/tests/Unit/Schema/SecurityTest.php
index f6806f9f19..4f7d648daa 100644
--- a/tests/Unit/Schema/SecurityTest.php
+++ b/tests/Unit/Schema/SecurityTest.php
@@ -13,7 +13,7 @@ public function testSetMaxComplexityThroughConfig(): void
     {
         config(['lighthouse.security.max_query_complexity' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -21,7 +21,7 @@ public function testSetMaxComplexityThroughConfig(): void
         type User {
             name: String
         }
-        ';
+        GRAPHQL;
 
         $this->assertMaxQueryComplexityIs1();
     }
@@ -30,7 +30,7 @@ public function testSetMaxDepthThroughConfig(): void
     {
         config(['lighthouse.security.max_query_depth' => 1]);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             user: User @first
         }
@@ -39,7 +39,7 @@ public function testSetMaxDepthThroughConfig(): void
             name: String
             user: User
         }
-        ';
+        GRAPHQL;
 
         $this->assertMaxQueryDepthIs1();
     }
@@ -53,20 +53,20 @@ public function testDisableIntrospectionThroughConfig(): void
 
     private function assertMaxQueryComplexityIs1(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 name
             }
         }
-        ')->assertGraphQLErrorMessage(
+        GRAPHQL)->assertGraphQLErrorMessage(
             QueryComplexity::maxQueryComplexityErrorMessage(1, 2),
         );
     }
 
     private function assertMaxQueryDepthIs1(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             user {
                 user {
@@ -76,14 +76,14 @@ private function assertMaxQueryDepthIs1(): void
                 }
             }
         }
-        ')->assertGraphQLErrorMessage(
+        GRAPHQL)->assertGraphQLErrorMessage(
             QueryDepth::maxQueryDepthErrorMessage(1, 2),
         );
     }
 
     private function assertIntrospectionIsDisabled(): void
     {
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             __schema {
                 queryType {
@@ -91,7 +91,7 @@ private function assertIntrospectionIsDisabled(): void
                 }
             }
         }
-        ')->assertGraphQLErrorMessage(
+        GRAPHQL)->assertGraphQLErrorMessage(
             DisableIntrospection::introspectionDisabledMessage(),
         );
     }
diff --git a/tests/Unit/Schema/TypeRegistryTest.php b/tests/Unit/Schema/TypeRegistryTest.php
index 845e721a4b..37a1bb02a3 100644
--- a/tests/Unit/Schema/TypeRegistryTest.php
+++ b/tests/Unit/Schema/TypeRegistryTest.php
@@ -30,11 +30,11 @@ protected function setUp(): void
 
     public function testSetsEnumValueThroughDirective(): void
     {
-        $enumNode = Parser::enumTypeDefinition(/** @lang GraphQL */ '
+        $enumNode = Parser::enumTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         enum Role {
             ADMIN @enum(value: 123)
         }
-        ');
+        GRAPHQL);
 
         $enumType = $this->typeRegistry->handle($enumNode);
         $this->assertInstanceOf(EnumType::class, $enumType);
@@ -49,11 +49,11 @@ enum Role {
 
     public function testDefaultsEnumValueToItsName(): void
     {
-        $enumNode = Parser::enumTypeDefinition(/** @lang GraphQL */ '
+        $enumNode = Parser::enumTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         enum Role {
             EMPLOYEE
         }
-        ');
+        GRAPHQL);
 
         $enumType = $this->typeRegistry->handle($enumNode);
         $this->assertInstanceOf(EnumType::class, $enumType);
@@ -68,9 +68,9 @@ enum Role {
 
     public function testTransformScalars(): void
     {
-        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ '
+        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         scalar Email
-        ');
+        GRAPHQL);
 
         $scalarType = $this->typeRegistry->handle($scalarNode);
         $this->assertInstanceOf(ScalarType::class, $scalarType);
@@ -80,9 +80,9 @@ public function testTransformScalars(): void
 
     public function testPointToScalarClassThroughDirective(): void
     {
-        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ '
-        scalar DateTime @scalar(class: "Nuwave\\\Lighthouse\\\Schema\\\Types\\\Scalars\\\DateTime")
-        ');
+        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
+        scalar DateTime @scalar(class: "Nuwave\\Lighthouse\\Schema\\Types\\Scalars\\DateTime")
+        GRAPHQL);
 
         $scalarType = $this->typeRegistry->handle($scalarNode);
         $this->assertInstanceOf(ScalarType::class, $scalarType);
@@ -92,9 +92,9 @@ public function testPointToScalarClassThroughDirective(): void
 
     public function testPointToScalarClassThroughDirectiveWithoutNamespace(): void
     {
-        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ '
+        $scalarNode = Parser::scalarTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         scalar SomeEmail @scalar(class: "Email")
-        ');
+        GRAPHQL);
 
         $scalarType = $this->typeRegistry->handle($scalarNode);
         $this->assertInstanceOf(ScalarType::class, $scalarType);
@@ -112,11 +112,11 @@ public function testTransformInterfaces(): void
         ]);
         $this->typeRegistry->overwrite($bar);
 
-        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ '
+        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         interface Foo implements Bar {
             bar: String
         }
-        ');
+        GRAPHQL);
 
         $interfaceType = $this->typeRegistry->handle($interfaceNode);
         $this->assertInstanceOf(InterfaceType::class, $interfaceType);
@@ -128,11 +128,11 @@ interface Foo implements Bar {
 
     public function testResolvesInterfaceThoughNamespace(): void
     {
-        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ '
+        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         interface Nameable {
             bar: String
         }
-        ');
+        GRAPHQL);
 
         $interfaceType = $this->typeRegistry->handle($interfaceNode);
         $this->assertInstanceOf(InterfaceType::class, $interfaceType);
@@ -142,11 +142,11 @@ interface Nameable {
 
     public function testResolvesInterfaceThoughSecondaryNamespace(): void
     {
-        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ '
+        $interfaceNode = Parser::interfaceTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         interface Bar {
             bar: String
         }
-        ');
+        GRAPHQL);
 
         $interfaceType = $this->typeRegistry->handle($interfaceNode);
         $this->assertInstanceOf(InterfaceType::class, $interfaceType);
@@ -156,9 +156,9 @@ interface Bar {
 
     public function testTransformUnions(): void
     {
-        $unionNode = Parser::unionTypeDefinition(/** @lang GraphQL */ '
+        $unionNode = Parser::unionTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         union Foo = Bar
-        ');
+        GRAPHQL);
 
         $unionType = $this->typeRegistry->handle($unionNode);
         $this->assertInstanceOf(UnionType::class, $unionType);
@@ -169,11 +169,11 @@ public function testTransformUnions(): void
 
     public function testTransformObjectTypes(): void
     {
-        $objectTypeNode = Parser::objectTypeDefinition(/** @lang GraphQL */ '
+        $objectTypeNode = Parser::objectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         type User {
             foo(bar: String! @hash): String!
         }
-        ');
+        GRAPHQL);
 
         $objectType = $this->typeRegistry->handle($objectTypeNode);
         $this->assertInstanceOf(ObjectType::class, $objectType);
@@ -184,11 +184,11 @@ public function testTransformObjectTypes(): void
 
     public function testTransformInputObjectTypes(): void
     {
-        $inputNode = Parser::inputObjectTypeDefinition(/** @lang GraphQL */ '
+        $inputNode = Parser::inputObjectTypeDefinition(/** @lang GraphQL */ <<<'GRAPHQL'
         input UserInput {
             foo: String!
         }
-        ');
+        GRAPHQL);
 
         $inputObjectType = $this->typeRegistry->handle($inputNode);
         $this->assertInstanceOf(InputObjectType::class, $inputObjectType);
@@ -299,11 +299,11 @@ public function testPossibleTypes(): void
     {
         $documentTypeName = 'Foo';
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type {$documentTypeName} {
             foo: ID
         }
-        " . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $this->app->forgetInstance(ASTBuilder::class);
         $astBuilder = $this->app->make(ASTBuilder::class);
@@ -335,11 +335,11 @@ public function testPossibleTypesMaintainsSingletons(): void
     {
         $documentTypeName = 'Foo';
 
-        $this->schema = /** @lang GraphQL */ "
+        $this->schema = /** @lang GraphQL */ <<<GRAPHQL
         type {$documentTypeName} {
             foo: ID
         }
-        " . self::PLACEHOLDER_QUERY;
+        GRAPHQL . self::PLACEHOLDER_QUERY;
 
         $this->app->forgetInstance(ASTBuilder::class);
         $astBuilder = $this->app->make(ASTBuilder::class);
diff --git a/tests/Unit/Schema/Types/LaravelEnumTypeTest.php b/tests/Unit/Schema/Types/LaravelEnumTypeTest.php
index 59289cba90..5f482f9946 100644
--- a/tests/Unit/Schema/Types/LaravelEnumTypeTest.php
+++ b/tests/Unit/Schema/Types/LaravelEnumTypeTest.php
@@ -73,8 +73,7 @@ enum PartiallyDeprecated {
   "Deprecated with reason"
   DEPRECATED_WITH_REASON @deprecated(reason: "some reason")
 }
-GRAPHQL
-                ,
+GRAPHQL,
                 SchemaPrinter::printType($enumType),
             );
         } else {
@@ -89,8 +88,7 @@ enum PartiallyDeprecated {
   "Deprecated with reason"
   DEPRECATED_WITH_REASON @deprecated(reason: "some reason")
 }
-GRAPHQL
-                ,
+GRAPHQL,
                 SchemaPrinter::printType($enumType),
             );
         }
@@ -98,11 +96,11 @@ enum PartiallyDeprecated {
 
     public function testReceivesEnumInstanceInternally(): void
     {
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(bar: AOrB): Boolean @mock
         }
-        ';
+        GRAPHQL;
 
         $this->typeRegistry->register(
             new LaravelEnumType(AOrB::class),
@@ -111,11 +109,11 @@ public function testReceivesEnumInstanceInternally(): void
         $this->mockResolver()
             ->with(null, new Callback(static fn (array $args): bool => $args['bar'] instanceof AOrB));
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(bar: A)
         }
-        ');
+        GRAPHQL);
     }
 
     public function testClassDoesNotExist(): void
diff --git a/tests/Unit/Subscriptions/Storage/CacheStorageManagerTest.php b/tests/Unit/Subscriptions/Storage/CacheStorageManagerTest.php
index 02a08ea479..bd2561db2a 100644
--- a/tests/Unit/Subscriptions/Storage/CacheStorageManagerTest.php
+++ b/tests/Unit/Subscriptions/Storage/CacheStorageManagerTest.php
@@ -34,7 +34,9 @@ private function subscriber(string $queryString): Subscriber
 
     public function testStoreAndRetrieveByChannel(): void
     {
-        $subscriber = $this->subscriber(/** @lang GraphQL */ '{ me }');
+        $subscriber = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { me }
+        GRAPHQL);
         $this->storage->storeSubscriber($subscriber, 'foo');
 
         $this->assertSubscriberIsSame(
@@ -46,13 +48,19 @@ public function testStoreAndRetrieveByChannel(): void
     public function testStoreAndRetrieveByTopics(): void
     {
         $fooTopic = 'foo';
-        $fooSubscriber1 = $this->subscriber(/** @lang GraphQL */ '{ me }');
-        $fooSubscriber2 = $this->subscriber(/** @lang GraphQL */ '{ viewer }');
+        $fooSubscriber1 = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { me }
+        GRAPHQL);
+        $fooSubscriber2 = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { viewer }
+        GRAPHQL);
         $this->storage->storeSubscriber($fooSubscriber1, $fooTopic);
         $this->storage->storeSubscriber($fooSubscriber2, $fooTopic);
 
         $barTopic = 'bar';
-        $barSubscriber = $this->subscriber(/** @lang GraphQL */ '{ bar }');
+        $barSubscriber = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { bar }
+        GRAPHQL);
         $this->storage->storeSubscriber($barSubscriber, $barTopic);
 
         $fooSubscribers = $this->storage->subscribersByTopic($fooTopic);
@@ -64,8 +72,12 @@ public function testStoreAndRetrieveByTopics(): void
 
     public function testDeleteSubscribersInCache(): void
     {
-        $subscriber1 = $this->subscriber(/** @lang GraphQL */ '{ me }');
-        $subscriber2 = $this->subscriber(/** @lang GraphQL */ '{ viewer }');
+        $subscriber1 = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { me }
+        GRAPHQL);
+        $subscriber2 = $this->subscriber(/** @lang GraphQL */ <<<'GRAPHQL'
+        { viewer }
+        GRAPHQL);
 
         $topic = 'foo';
         $this->storage->storeSubscriber($subscriber1, $topic);
diff --git a/tests/Unit/Testing/MakesGraphQLRequestsTest.php b/tests/Unit/Testing/MakesGraphQLRequestsTest.php
index 257aeea223..a3569e3ac7 100644
--- a/tests/Unit/Testing/MakesGraphQLRequestsTest.php
+++ b/tests/Unit/Testing/MakesGraphQLRequestsTest.php
@@ -32,26 +32,26 @@ public function testRethrowGraphQLErrors(): void
             throw $error;
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ')->assertGraphQLError($error);
+        GRAPHQL)->assertGraphQLError($error);
 
         $this->rethrowGraphQLErrors();
 
         $this->expectExceptionObject($error);
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo
         }
-        ');
+        GRAPHQL);
     }
 
     public function testGraphQLWithHeaders(): void
@@ -62,22 +62,24 @@ public function testGraphQLWithHeaders(): void
             $request = $this->app->make(Request::class);
         });
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo: ID @mock
         }
-        ';
+        GRAPHQL;
 
         $key = 'foo';
         $value = 'bar';
 
         $this->graphQL(
             /** @lang GraphQL */
-            '
+            <<<'GRAPHQL'
+
             {
                 foo
             }
-            ',
+            
+            GRAPHQL,
             [],
             [],
             [$key => $value],
diff --git a/tests/Unit/Testing/MocksResolversTest.php b/tests/Unit/Testing/MocksResolversTest.php
index 1595961a93..66d1020d9f 100644
--- a/tests/Unit/Testing/MocksResolversTest.php
+++ b/tests/Unit/Testing/MocksResolversTest.php
@@ -14,17 +14,17 @@ public function testCallsMock(): void
             ])
             ->willReturn(2);
 
-        $this->schema = /** @lang GraphQL */ '
+        $this->schema = /** @lang GraphQL */ <<<'GRAPHQL'
         type Query {
             foo(foo: Int): Int @mock
         }
-        ';
+        GRAPHQL;
 
-        $this->graphQL(/** @lang GraphQL */ '
+        $this->graphQL(/** @lang GraphQL */ <<<'GRAPHQL'
         {
             foo(foo: 1)
         }
-        ')->assertExactJson([
+        GRAPHQL)->assertExactJson([
             'data' => [
                 'foo' => 2,
             ],