Merge pull request #4512 from StyleShit/feat/typedef-var-as-const

[eslint-plugin]: Allow using `as const` in `typedef-var`
microsoft · Feb 6, 2024 · 8752399 · 8752399
2 parents fe1cbf4 + b75b160
commit 8752399
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diff --git a/common/changes/@rushstack/eslint-plugin/feat-typedef-var-as-const_2024-02-05-18-53.json b/common/changes/@rushstack/eslint-plugin/feat-typedef-var-as-const_2024-02-05-18-53.json
@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/eslint-plugin",
+      "comment": "Allow using `as const` in `typedef-var`",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@rushstack/eslint-plugin"
+}
diff --git a/eslint/eslint-plugin/src/test/typedef-var.test.ts b/eslint/eslint-plugin/src/test/typedef-var.test.ts
@@ -46,6 +46,15 @@ ruleTester.run('typedef-var', typedefVar, {
     {
       code: 'for (const x of []) { }'
     },
+    {
+      code: 'const x = 1 as const;'
+    },
+    {
+      code: 'const x: 1 = 1;'
+    },
+    {
+      code: 'const x: number = 1;'
+    },
     {
       // prettier-ignore
       code: [

diff --git a/eslint/eslint-plugin/src/typedef-var.ts b/eslint/eslint-plugin/src/typedef-var.ts
@@ -50,6 +50,16 @@ const typedefVar: TSESLint.RuleModule<MessageIds, Options> = {
           return;
         }
 
+        if (
+          node.init?.type === AST_NODE_TYPES.TSAsExpression &&
+          node.init.typeAnnotation.type === AST_NODE_TYPES.TSTypeReference &&
+          node.init.typeAnnotation.typeName.type === AST_NODE_TYPES.Identifier &&
+          node.init.typeAnnotation.typeName.name === 'const'
+        ) {
+          // An `as const` type declaration was provided
+          return;
+        }
+
         // These are @typescript-eslint/typedef exemptions
         if (
           node.id.type === AST_NODE_TYPES.ArrayPattern /* ArrayDestructuring */ ||