Add multiple parsers for test cases

tests/src/rules/no-duplicates.js

@@ -129,29 +129,32 @@ ruleTester.run('no-duplicates', rule, {
       errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
     }),
 
-    // #2347: duplicate identifiers should be removed
-    test({
-      code: "import {a} from './foo'; import { a } from './foo'",
-      output: "import {a} from './foo'; ",
-      errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
-      parser: parsers.BABEL_OLD, // Needed to avoid "A fatal parsing error occurred: Parsing error: Identifier 'a' has already been declared"
-    }),
+    // These test cases use duplicate import identifiers, which causes a fatal parsing error using ESPREE (default) and TS_OLD.
+    ...[parsers.BABEL_OLD, parsers.TS_NEW].flatMap((parser => [
+      // #2347: duplicate identifiers should be removed
+      test({
+        code: "import {a} from './foo'; import { a } from './foo'",
+        output: "import {a} from './foo'; ",
+        errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
+        parser,
+      }),
 
-    // #2347: duplicate identifiers should be removed
-    test({
-      code: "import {a,b} from './foo'; import { b, c } from './foo'; import {b,c,d} from './foo'",
-      output: "import {a,b, c ,d} from './foo';  ",
-      errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
-      parser: parsers.BABEL_OLD, // Needed to avoid "A fatal parsing error occurred: Parsing error: Identifier 'b' has already been declared"
-    }),
+      // #2347: duplicate identifiers should be removed
+      test({
+        code: "import {a,b} from './foo'; import { b, c } from './foo'; import {b,c,d} from './foo'",
+        output: "import {a,b, c ,d} from './foo';  ",
+        errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
+        parser,
+      }),
 
-    // #2347: duplicate identifiers should be removed, but not if they are adjacent to comments
-    test({
-      code: "import {a} from './foo'; import { a/*,b*/ } from './foo'",
-      output: "import {a, a/*,b*/ } from './foo'; ",
-      errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
-      parser: parsers.BABEL_OLD, // Needed to avoid "A fatal parsing error occurred: Parsing error: Identifier 'a' has already been declared"
-    }),
+      // #2347: duplicate identifiers should be removed, but not if they are adjacent to comments
+      test({
+        code: "import {a} from './foo'; import { a/*,b*/ } from './foo'",
+        output: "import {a, a/*,b*/ } from './foo'; ",
+        errors: ['\'./foo\' imported multiple times.', '\'./foo\' imported multiple times.'],
+        parser,
+      }),
+    ])),
 
     test({
       code: "import {x} from './foo'; import {} from './foo'; import {/*c*/} from './foo'; import {y} from './foo'",