From e52e13d0b1b70d394b278e0ed5e851cfb1046e4e Mon Sep 17 00:00:00 2001
From: ZLoo <Kozlov.s.v.1992@gmail.com>
Date: Sun, 21 Jul 2024 21:20:06 +0300
Subject: [PATCH] Fix warning CA1062#AsyncNoOpPolicy

---
 src/Polly/NoOp/AsyncNoOpPolicy.cs             | 23 +++++++++++++++----
 test/Polly.Specs/NoOp/NoOpAsyncSpecs.cs       | 19 +++++++++++++++
 .../Polly.Specs/NoOp/NoOpTResultAsyncSpecs.cs | 18 +++++++++++++++
 3 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/src/Polly/NoOp/AsyncNoOpPolicy.cs b/src/Polly/NoOp/AsyncNoOpPolicy.cs
index 0eb7eef5e3c..277dad9640e 100644
--- a/src/Polly/NoOp/AsyncNoOpPolicy.cs
+++ b/src/Polly/NoOp/AsyncNoOpPolicy.cs
@@ -4,7 +4,6 @@ namespace Polly.NoOp;
 /// <summary>
 /// A noop policy that can be applied to asynchronous delegates.
 /// </summary>
-#pragma warning disable CA1062 // Validate arguments of public methods
 public class AsyncNoOpPolicy : AsyncPolicy, INoOpPolicy
 {
     internal AsyncNoOpPolicy()
@@ -14,8 +13,15 @@ internal AsyncNoOpPolicy()
     /// <inheritdoc/>
     [DebuggerStepThrough]
     protected override Task<TResult> ImplementationAsync<TResult>(Func<Context, CancellationToken, Task<TResult>> action, Context context, CancellationToken cancellationToken,
-        bool continueOnCapturedContext) =>
-        NoOpEngine.ImplementationAsync(action, context, cancellationToken);
+        bool continueOnCapturedContext)
+    {
+        if (action is null)
+        {
+            throw new ArgumentNullException(nameof(action));
+        }
+
+        return NoOpEngine.ImplementationAsync(action, context, cancellationToken);
+    }
 }
 
 /// <summary>
@@ -31,6 +37,13 @@ internal AsyncNoOpPolicy()
     /// <inheritdoc/>
     [DebuggerStepThrough]
     protected override Task<TResult> ImplementationAsync(Func<Context, CancellationToken, Task<TResult>> action, Context context, CancellationToken cancellationToken,
-        bool continueOnCapturedContext) =>
-        NoOpEngine.ImplementationAsync(action, context, cancellationToken);
+        bool continueOnCapturedContext)
+    {
+        if (action is null)
+        {
+            throw new ArgumentNullException(nameof(action));
+        }
+
+        return NoOpEngine.ImplementationAsync(action, context, cancellationToken);
+    }
 }
diff --git a/test/Polly.Specs/NoOp/NoOpAsyncSpecs.cs b/test/Polly.Specs/NoOp/NoOpAsyncSpecs.cs
index c94cf069ea0..b89b21bb1fe 100644
--- a/test/Polly.Specs/NoOp/NoOpAsyncSpecs.cs
+++ b/test/Polly.Specs/NoOp/NoOpAsyncSpecs.cs
@@ -2,6 +2,25 @@
 
 public class NoOpAsyncSpecs
 {
+    [Fact]
+    public void Should_throw_when_action_is_null()
+    {
+        var flags = BindingFlags.NonPublic | BindingFlags.Instance;
+        Func<Context, CancellationToken, Task<EmptyStruct>> action = null!;
+
+        var instance = Activator.CreateInstance(typeof(AsyncNoOpPolicy), true)!;
+        var instanceType = instance.GetType();
+        var methods = instanceType.GetMethods(flags);
+        var methodInfo = methods.First(method => method is { Name: "ImplementationAsync", ReturnType.Name: "Task`1" });
+        var generic = methodInfo.MakeGenericMethod(typeof(EmptyStruct));
+
+        var func = () => generic.Invoke(instance, [action, new Context(), CancellationToken.None, false]);
+
+        var exceptionAssertions = func.Should().Throw<TargetInvocationException>();
+        exceptionAssertions.And.Message.Should().Be("Exception has been thrown by the target of an invocation.");
+        exceptionAssertions.WithInnerException<ArgumentNullException>("action");
+    }
+
     [Fact]
     public async Task Should_execute_user_delegate()
     {
diff --git a/test/Polly.Specs/NoOp/NoOpTResultAsyncSpecs.cs b/test/Polly.Specs/NoOp/NoOpTResultAsyncSpecs.cs
index b8f9b3b18bc..03e24cf3c16 100644
--- a/test/Polly.Specs/NoOp/NoOpTResultAsyncSpecs.cs
+++ b/test/Polly.Specs/NoOp/NoOpTResultAsyncSpecs.cs
@@ -2,6 +2,24 @@
 
 public class NoOpTResultAsyncSpecs
 {
+    [Fact]
+    public void Should_throw_when_action_is_null()
+    {
+        var flags = BindingFlags.NonPublic | BindingFlags.Instance;
+        Func<Context, CancellationToken, Task<EmptyStruct>> action = null!;
+
+        var instance = Activator.CreateInstance(typeof(AsyncNoOpPolicy<EmptyStruct>), true)!;
+        var instanceType = instance.GetType();
+        var methods = instanceType.GetMethods(flags);
+        var methodInfo = methods.First(method => method is { Name: "ImplementationAsync", ReturnType.Name: "Task`1" });
+
+        var func = () => methodInfo.Invoke(instance, [action, new Context(), CancellationToken.None, false]);
+
+        var exceptionAssertions = func.Should().Throw<TargetInvocationException>();
+        exceptionAssertions.And.Message.Should().Be("Exception has been thrown by the target of an invocation.");
+        exceptionAssertions.WithInnerException<ArgumentNullException>("action");
+    }
+
     [Fact]
     public async Task Should_execute_user_delegate()
     {