test: add test for metroPlatformResolver

packages/community-cli-plugin/src/utils/__tests__/metroPlatformResolver-test.js

@@ -0,0 +1,110 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+import type {CustomResolutionContext} from 'metro-resolver/src/types';
+
+import {reactNativePlatformResolver} from '../metroPlatformResolver';
+
+jest.dontMock('../metroPlatformResolver');
+
+describe('reactNativePlatformResolver', () => {
+  let resolveRequest = jest.fn();
+  let metroContextMock: Partial<{...CustomResolutionContext}> = {
+    customResolverOptions: {},
+    resolveRequest,
+  };
+  beforeEach(() => {
+    resolveRequest.mockReset();
+  });
+
+  test('forwards non react-native module', () => {
+    reactNativePlatformResolver({visionos: 'react-native-visionos'})(
+      // $FlowFixMe[incompatible-call]
+      metroContextMock,
+      'module-name',
+      'ios',
+    );
+
+    expect(resolveRequest).toHaveBeenCalledWith(
+      metroContextMock,
+      'module-name',
+      'ios',
+    );
+  });
+
+  test('rewrites react-native module to out-of-tree platform "macos"', () => {
+    reactNativePlatformResolver({macos: 'react-native-macos'})(
+      // $FlowFixMe[incompatible-call]
+      metroContextMock,
+      'react-native',
+      'macos',
+    );
+
+    expect(resolveRequest).toHaveBeenCalledWith(
+      metroContextMock,
+      'react-native-macos',
+      'macos',
+    );
+  });
+
+  test('rewrites internal react-native/Libraries/Utilities/Platform path to out-of-tree platform "macos"', () => {
+    reactNativePlatformResolver({macos: 'react-native-macos'})(
+      // $FlowFixMe[incompatible-call]
+      metroContextMock,
+      'react-native/Libraries/Utilities/Platform',
+      'macos',
+    );
+
+    expect(resolveRequest).toHaveBeenCalledWith(
+      metroContextMock,
+      'react-native-macos/Libraries/Utilities/Platform',
+      'macos',
+    );
+  });
+
+  test('rewrites react-native module to out-of-tree variant "visionos" based on "ios" platform', () => {
+    const metroContextMockWithVariant: Partial<{...CustomResolutionContext}> = {
+      ...metroContextMock,
+      customResolverOptions: {variant: 'visionos'},
+    };
+    reactNativePlatformResolver({visionos: 'react-native-visionos'})(
+      // $FlowFixMe[incompatible-call]
+      metroContextMockWithVariant,
+      'react-native',
+      'ios',
+    );
+
+    expect(resolveRequest).toHaveBeenCalledWith(
+      metroContextMockWithVariant,
+      'react-native-visionos',
+      'ios',
+    );
+  });
+
+  test('rewrites internal react-native/Libraries/Utilities/Platform path to out-of-tree variant "visionos" based on "ios" platform', () => {
+    const metroContextMockWithVariant: Partial<{...CustomResolutionContext}> = {
+      ...metroContextMock,
+      customResolverOptions: {variant: 'visionos'},
+    };
+    reactNativePlatformResolver({visionos: 'react-native-visionos'})(
+      // $FlowFixMe[incompatible-call]
+      metroContextMockWithVariant,
+      'react-native/Libraries/Utilities/Platform',
+      'ios',
+    );
+
+    expect(resolveRequest).toHaveBeenCalledWith(
+      metroContextMockWithVariant,
+      'react-native-visionos/Libraries/Utilities/Platform',
+      'ios',
+    );
+  });
+});