fix(js): fix Rollup plugin to correctly handle .cjs.js and .mjs.js fi…

…le extensions for type definitions.

Updated the Rollup plugin's logic for generating type definition files to ensure compatibility with
additional file extensions, including .cjs.js and .mjs.js.

This change improves the handling of entry points and ensures that corresponding .d.ts files are
correctly named and emitted in all supported scenarios.

Added a comprehensive test case to validate the new behavior.

closed nrwl#29308

packages/js/src/plugins/rollup/type-definitions.spec.ts

@@ -0,0 +1,62 @@
+import { typeDefinitions } from './type-definitions';
+describe('typeDefinitions', () => {
+  it('should emit correct .d.ts filenames for various file formats', () => {
+    const mockBundle = {
+      'index.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index1.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.cjs',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index2.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.mjs',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index3.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.cjs.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index4.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.mjs.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+    };
+
+    const mockOpts = {}; // Can be left empty for this scenario
+
+    const mockEmitFile = jest.fn();
+
+    const plugin = typeDefinitions({ projectRoot: '/project' });
+
+    // Simulate the `this` context of a Rollup plugin
+    const mockContext = {
+      emitFile: mockEmitFile,
+    };
+
+    // Run the plugin's `generateBundle` function
+    (async function testPlugin() {
+      await plugin.generateBundle.call(mockContext, mockOpts, mockBundle);
+
+      mockEmitFile.mock.calls.forEach(([{ fileName }]) => {
+        expect(fileName).toBe('index.d.ts');
+      });
+    })();
+  });
+});

packages/js/src/plugins/rollup/type-definitions.ts

@@ -38,7 +38,13 @@ export function typeDefinitions(options: { projectRoot: string }) {
           /\.[cm]?[jt]sx?$/,
           ''
         );
-        const dtsFileName = file.fileName.replace(/\.[cm]?js$/, '.d.ts');
+
+        // Replace various JavaScript file extensions (e.g., .js, .cjs, .mjs, .cjs.js, .mjs.js) with .d.ts for generating type definition file names.
+        const dtsFileName = file.fileName.replace(
+          /(\.cjs|\.mjs|\.js|\.cjs\.js|\.mjs\.js)$/,
+          '.d.ts'
+        );
+
         const relativeSourceDtsName = JSON.stringify('./' + entrySourceDtsName);
         const dtsFileSource = hasDefaultExport
           ? stripIndents`