fix(eslint-plugin): [no-shadow] fix false-positive on enum declaration (

#2374)
typescript-eslint · Aug 29, 2020 · 9de669f · 9de669f
1 parent a9cd6fb
commit 9de669f
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diff --git a/packages/eslint-plugin/src/rules/no-shadow.ts b/packages/eslint-plugin/src/rules/no-shadow.ts
@@ -116,6 +116,25 @@ export default util.createRule<Options, MessageIds>({
       );
     }
 
+    /**
+     * Checks if a variable of the class name in the class scope of ClassDeclaration.
+     *
+     * ClassDeclaration creates two variables of its name into its outer scope and its class scope.
+     * So we should ignore the variable in the class scope.
+     * @param variable The variable to check.
+     * @returns Whether or not the variable of the class name in the class scope of ClassDeclaration.
+     */
+    function isDuplicatedEnumNameVariable(
+      variable: TSESLint.Scope.Variable,
+    ): boolean {
+      const block = variable.scope.block;
+
+      return (
+        block.type === AST_NODE_TYPES.TSEnumDeclaration &&
+        block.id === variable.identifiers[0]
+      );
+    }
+
     /**
      * Checks if a variable is inside the initializer of scopeVar.
      *
@@ -233,6 +252,11 @@ export default util.createRule<Options, MessageIds>({
           continue;
         }
 
+        // ignore variables of a class name in the class scope of ClassDeclaration
+        if (isDuplicatedEnumNameVariable(variable)) {
+          continue;
+        }
+
         // ignore configured allowed names
         if (isAllowed(variable)) {
           continue;

diff --git a/packages/eslint-plugin/tests/rules/no-shadow.test.ts b/packages/eslint-plugin/tests/rules/no-shadow.test.ts
@@ -431,6 +431,13 @@ function foo(cb) {
       `,
       options: [{ allow: ['cb'] }],
     },
+    // https://github.com/typescript-eslint/typescript-eslint/issues/2360
+    `
+enum Direction {
+  left = 'left',
+  right = 'right',
+}
+    `,
   ],
   invalid: [
     {