Reduce false positives in no-duplicate-constant-values for numeric constants

eslint-factory/src/rules/no-duplicate-constant-values.test.ts

@@ -23,6 +23,10 @@ describe("no-duplicate-constant-values", () => {
         `let first = "same"; let second = "same";`,
         `const { first, second } = value;`,
         `function first() { const VALUE = "same"; } function second() { const VALUE = "same"; }`,
+        `const DEFAULT_HTTP_TIMEOUT_MS = 15000; const TOOL_CALL_TIMEOUT_BUFFER_MS = 15000;`,
+        `const NOTIFY_TIMEOUT_MS = 10000; const KEEPALIVE_PING_INTERVAL_MS = 10000;`,
+        `const A_PREFIX_LENGTH = 2; const B_PREFIX_LENGTH = 2;`,
+        `const DEFAULT_HTTP_TIMEOUT_MS = 15000; const TOOL_CALL_TIMEOUT_BUFFER_MS = 15000; const NOTIFY_TIMEOUT_MS = 10000; const KEEPALIVE_PING_INTERVAL_MS = 10000;`,
       ],
       invalid: [],
     });
@@ -41,8 +45,11 @@ describe("no-duplicate-constant-values", () => {
           errors: [{ messageId: "duplicateConstantValue", data: { name: "SECOND", originalName: "FIRST", value: `"same"` } }],
         },
         {
-          code: `const FIRST = -42; const SECOND = -42; const THIRD = 42;`,
-          errors: [{ messageId: "duplicateConstantValue", data: { name: "SECOND", originalName: "FIRST", value: "-42" } }],
+          code: `const FIRST = -42; const SECOND = -42; const THIRD = -42;`,
+          errors: [
+            { messageId: "duplicateConstantValue", data: { name: "SECOND", originalName: "FIRST", value: "-42" } },
+            { messageId: "duplicateConstantValue", data: { name: "THIRD", originalName: "FIRST", value: "-42" } },
+          ],
         },
         {
           code: `const FIRST = /value/gi; const SECOND = /value/gi;`,
@@ -56,6 +63,13 @@ describe("no-duplicate-constant-values", () => {
     });
   });
 
+  it("requires at least three matching numeric constants before reporting duplicates", () => {
+    ruleTester.run("no-duplicate-constant-values", noDuplicateConstantValuesRule, {
+      valid: [`const FIRST = -42; const SECOND = -42;`],
+      invalid: [],
+    });
+  });
+
   it("reports every duplicate after the first declaration", () => {
     ruleTester.run("no-duplicate-constant-values", noDuplicateConstantValuesRule, {
       valid: [],

eslint-factory/src/rules/no-duplicate-constant-values.ts

@@ -4,8 +4,11 @@ const createRule = ESLintUtils.RuleCreator(name => `https://github.com/github/gh
 
 interface ConstantDeclaration {
   name: string;
+  declaration: TSESTree.VariableDeclarator;
 }
 
+const MIN_NUMERIC_DUPLICATE_GROUP_SIZE = 3;
+
 function getStaticValueKey(node: TSESTree.Expression): string | null {
   if (node.type === AST_NODE_TYPES.Literal) {
     if ("regex" in node && node.regex) {
@@ -39,7 +42,7 @@ export const noDuplicateConstantValuesRule = createRule({
   },
   defaultOptions: [],
   create(context) {
-    const constantsByValue = new Map<string, ConstantDeclaration>();
+    const constantsByValue = new Map<string, ConstantDeclaration[]>();
 
     return {
       VariableDeclaration(node) {
@@ -57,25 +60,42 @@ export const noDuplicateConstantValuesRule = createRule({
             continue;
           }
 
-          const original = constantsByValue.get(valueKey);
-          if (!original) {
-            constantsByValue.set(valueKey, {
-              name: declaration.id.name,
-            });
+          const declarationsForValue = constantsByValue.get(valueKey);
+          if (!declarationsForValue) {
+            constantsByValue.set(valueKey, [
+              {
+                name: declaration.id.name,
+                declaration,
+              },
+            ]);
             continue;
           }
 
-          context.report({
-            node: declaration,
-            messageId: "duplicateConstantValue",
-            data: {
-              name: declaration.id.name,
-              originalName: original.name,
-              value: context.sourceCode.getText(declaration.init),
-            },
+          declarationsForValue.push({
+            name: declaration.id.name,
+            declaration,
           });
         }
       },
+      "Program:exit"() {
+        for (const [valueKey, declarations] of constantsByValue) {
+          const shouldReportDuplicates = declarations.length > 1 && (!valueKey.startsWith("number:") || declarations.length >= MIN_NUMERIC_DUPLICATE_GROUP_SIZE);
+          if (!shouldReportDuplicates) continue;
+
+          const original = declarations[0];
+          for (const duplicate of declarations.slice(1)) {
+            context.report({
+              node: duplicate.declaration,
+              messageId: "duplicateConstantValue",
+              data: {
+                name: duplicate.name,
+                originalName: original.name,
+                value: context.sourceCode.getText(duplicate.declaration.init!),
+              },
+            });
+          }
+        }
+      },
     };
   },
 });