fix(type-utils): checking of type aliases' type names by typeMatchesSpecifier (typescript-eslint#6820)

RebeccaStevens · web-flow · commit 7ca2c900eb07 · 2023-04-02T09:44:32.000-04:00
* fix(specifierNameMatches): check aliasSymbol if it exists

* test: type aliases
diff --git a/packages/type-utils/src/TypeOrValueSpecifier.ts b/packages/type-utils/src/TypeOrValueSpecifier.ts
@@ -120,7 +120,7 @@ function specifierNameMatches(type: ts.Type, name: string | string[]): boolean {
   if (typeof name === 'string') {
     name = [name];
   }
-  const symbol = type.getSymbol();
+  const symbol = type.aliasSymbol ?? type.getSymbol();
   if (symbol === undefined) {
     return false;
   }
diff --git a/packages/type-utils/tests/TypeOrValueSpecifier.test.ts b/packages/type-utils/tests/TypeOrValueSpecifier.test.ts
@@ -176,28 +176,42 @@ describe('TypeOrValueSpecifier', () => {
       runTestNegative,
     );
 
-    it.each<[string, TypeOrValueSpecifier]>([
+    it.each<[string, TypeOrValueSpecifier]>(
       [
-        'interface Foo {prop: string}; type Test = Foo;',
-        { from: 'file', name: 'Foo' },
-      ],
-      [
-        'interface Foo {prop: string}; type Test = Foo;',
-        { from: 'file', name: ['Foo', 'Bar'] },
-      ],
-      [
-        'interface Foo {prop: string}; type Test = Foo;',
-        { from: 'file', name: 'Foo', path: 'tests/fixtures/file.ts' },
-      ],
-      [
-        'interface Foo {prop: string}; type Test = Foo;',
-        {
-          from: 'file',
-          name: ['Foo', 'Bar'],
-          path: 'tests/fixtures/file.ts',
-        },
-      ],
-    ])('matches a matching file specifier: %s', runTestPositive);
+        [
+          'interface Foo {prop: string}; type Test = Foo;',
+          'type Foo = {prop: string}; type Test = Foo;',
+        ].map((test): [string, TypeOrValueSpecifier] => [
+          test,
+          { from: 'file', name: 'Foo' },
+        ]),
+        [
+          'interface Foo {prop: string}; type Test = Foo;',
+          'type Foo = {prop: string}; type Test = Foo;',
+        ].map((test): [string, TypeOrValueSpecifier] => [
+          test,
+          { from: 'file', name: ['Foo', 'Bar'] },
+        ]),
+        [
+          'interface Foo {prop: string}; type Test = Foo;',
+          'type Foo = {prop: string}; type Test = Foo;',
+        ].map((test): [string, TypeOrValueSpecifier] => [
+          test,
+          { from: 'file', name: 'Foo', path: 'tests/fixtures/file.ts' },
+        ]),
+        [
+          'interface Foo {prop: string}; type Test = Foo;',
+          'type Foo = {prop: string}; type Test = Foo;',
+        ].map((test): [string, TypeOrValueSpecifier] => [
+          test,
+          {
+            from: 'file',
+            name: ['Foo', 'Bar'],
+            path: 'tests/fixtures/file.ts',
+          },
+        ]),
+      ].flat(),
+    )('matches a matching file specifier: %s', runTestPositive);
 
     it.each<[string, TypeOrValueSpecifier]>([
       [

Original file line number	Diff line number	Diff line change
`@@ -120,7 +120,7 @@ function specifierNameMatches(type: ts.Type, name: string \| string[]): boolean {`
`120`	`120`	`if (typeof name === 'string') {`
`121`	`121`	`name = [name];`
`122`	`122`	`}`
`123`		`- const symbol = type.getSymbol();`
	`123`	`+ const symbol = type.aliasSymbol ?? type.getSymbol();`
`124`	`124`	`if (symbol === undefined) {`
`125`	`125`	`return false;`
`126`	`126`	`}`