Add function to create hard links for the app (#53675)

Summary:
Pull Request resolved: #53675

## Context

When configuring an app to build with SwiftPM from source, there is a sequence of operations we need to run in order to prepare the project correctly.

## Changed

Add a function that create hardlinks for React Native so it can build from source

## Changelog:
[Internal] -

Reviewed By: cortinico

Differential Revision: D81778454

fbshipit-source-id: 702a603629e4fad154b5d79dea6d96fcd80235b9

Author: cipolleschi

packages/react-native/scripts/swiftpm/__tests__/prepare-app-utils-test.js

@@ -12,6 +12,7 @@
 
 const {
   configureAppForSwift,
+  createHardlinks,
   findXcodeProjectDirectory,
   runIosPrebuild,
   runPodDeintegrate,
@@ -24,6 +25,12 @@ jest.mock('child_process');
 // Mock fs module
 jest.mock('fs');
 
+// Mock headers-utils module
+jest.mock('../headers-utils');
+
+// Mock prepare-app-dependencies-headers module
+jest.mock('../prepare-app-dependencies-headers');
+
 // Mock path module for absolute paths
 jest.mock('path', () => {
   const actualPath = jest.requireActual('path');
@@ -34,6 +41,204 @@ jest.mock('path', () => {
   };
 });
 
+describe('createHardlinks', () => {
+  let mockSymlinkReactNativeHeaders;
+  let mockSymlinkThirdPartyDependenciesHeaders;
+  let mockPath;
+  let mockConsoleLog;
+
+  beforeEach(() => {
+    // Setup mocks
+    const headersUtils = require('../headers-utils');
+    const prepareAppDependenciesHeaders = require('../prepare-app-dependencies-headers');
+
+    mockSymlinkReactNativeHeaders =
+      prepareAppDependenciesHeaders.symlinkReactNativeHeaders;
+    mockSymlinkThirdPartyDependenciesHeaders =
+      headersUtils.symlinkThirdPartyDependenciesHeaders;
+
+    mockPath = require('path');
+    mockConsoleLog = console.log;
+
+    // Clear and reset all mocks completely
+    jest.clearAllMocks();
+    jest.resetAllMocks();
+
+    // Set up fresh mock implementations
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {});
+    mockSymlinkThirdPartyDependenciesHeaders.mockImplementation(() => {});
+
+    // Mock path.join to return realistic paths
+    mockPath.join.mockImplementation((...args) => args.join('/'));
+  });
+
+  it('should create hard links successfully', async () => {
+    // Setup
+    const reactNativePath = '/path/to/react-native';
+
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {});
+    mockSymlinkThirdPartyDependenciesHeaders.mockImplementation(() => {});
+
+    // Execute
+    await createHardlinks(reactNativePath);
+
+    // Assert
+    const expectedReactIncludesPath = '/path/to/react-native/React';
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+    expect(mockSymlinkThirdPartyDependenciesHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledTimes(1);
+    expect(mockSymlinkThirdPartyDependenciesHeaders).toHaveBeenCalledTimes(1);
+
+    // Verify console output
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      'Creating hard links for React Native headers...',
+    );
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      '✓ React Native hard links created in React/includes',
+    );
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      'Creating hard links for third-party dependencies...',
+    );
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      '✓ Third-party dependencies hard links created in React/includes',
+    );
+  });
+
+  it('should throw error when symlinkReactNativeHeaders fails', async () => {
+    // Setup
+    const reactNativePath = '/path/to/react-native';
+    const originalError = new Error('React Native headers linking failed');
+
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {
+      throw originalError;
+    });
+
+    // Execute & Assert
+    await expect(createHardlinks(reactNativePath)).rejects.toThrow(
+      'Hard link creation failed: React Native headers linking failed',
+    );
+
+    const expectedReactIncludesPath = '/path/to/react-native/React';
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+    expect(mockSymlinkThirdPartyDependenciesHeaders).not.toHaveBeenCalled();
+
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      'Creating hard links for React Native headers...',
+    );
+    expect(mockConsoleLog).not.toHaveBeenCalledWith(
+      '✓ React Native hard links created in React/includes',
+    );
+  });
+
+  it('should throw error when symlinkThirdPartyDependenciesHeaders fails', async () => {
+    // Setup
+    const reactNativePath = '/path/to/react-native';
+    const originalError = new Error('Third-party dependencies linking failed');
+
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {});
+    mockSymlinkThirdPartyDependenciesHeaders.mockImplementation(() => {
+      throw originalError;
+    });
+
+    // Execute & Assert
+    await expect(createHardlinks(reactNativePath)).rejects.toThrow(
+      'Hard link creation failed: Third-party dependencies linking failed',
+    );
+
+    const expectedReactIncludesPath = '/path/to/react-native/React';
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+    expect(mockSymlinkThirdPartyDependenciesHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      'Creating hard links for React Native headers...',
+    );
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      '✓ React Native hard links created in React/includes',
+    );
+    expect(mockConsoleLog).toHaveBeenCalledWith(
+      'Creating hard links for third-party dependencies...',
+    );
+    expect(mockConsoleLog).not.toHaveBeenCalledWith(
+      '✓ Third-party dependencies hard links created in React/includes',
+    );
+  });
+
+  it('should handle different React Native paths correctly', async () => {
+    // Setup
+    const reactNativePath = '/Users/developer/custom-react-native-path';
+
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {});
+    mockSymlinkThirdPartyDependenciesHeaders.mockImplementation(() => {});
+
+    // Execute
+    await createHardlinks(reactNativePath);
+
+    // Assert
+    const expectedReactIncludesPath =
+      '/Users/developer/custom-react-native-path/React';
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+    expect(mockSymlinkThirdPartyDependenciesHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+  });
+
+  it('should handle paths with spaces correctly', async () => {
+    // Setup
+    const reactNativePath = '/path/to/react native project';
+
+    mockSymlinkReactNativeHeaders.mockImplementation(() => {});
+    mockSymlinkThirdPartyDependenciesHeaders.mockImplementation(() => {});
+
+    // Execute
+    await createHardlinks(reactNativePath);
+
+    // Assert
+    const expectedReactIncludesPath = '/path/to/react native project/React';
+
+    expect(mockSymlinkReactNativeHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+    expect(mockSymlinkThirdPartyDependenciesHeaders).toHaveBeenCalledWith(
+      reactNativePath,
+      expectedReactIncludesPath,
+      'includes',
+    );
+  });
+});
+
 // Mock console methods - disable React Native's strict console checking
 const originalConsole = global.console;
 

packages/react-native/scripts/swiftpm/prepare-app-utils.js

@@ -8,6 +8,10 @@
  * @format
  */
 
+const {symlinkThirdPartyDependenciesHeaders} = require('./headers-utils');
+const {
+  symlinkReactNativeHeaders,
+} = require('./prepare-app-dependencies-headers');
 const {execSync} = require('child_process');
 const fs = require('fs');
 const path = require('path');
@@ -206,10 +210,37 @@ async function setBuildFromSource(
   }
 }
 
+/**
+ * Create hard links for React Native headers in React/includes
+ */
+async function createHardlinks(
+  reactNativePath /*: string */,
+) /*: Promise<void> */ {
+  try {
+    console.log('Creating hard links for React Native headers...');
+    const reactIncludesPath = path.join(reactNativePath, 'React');
+    symlinkReactNativeHeaders(reactNativePath, reactIncludesPath, 'includes');
+    console.log('✓ React Native hard links created in React/includes');
+
+    console.log('Creating hard links for third-party dependencies...');
+    symlinkThirdPartyDependenciesHeaders(
+      reactNativePath,
+      reactIncludesPath,
+      'includes',
+    );
+    console.log(
+      '✓ Third-party dependencies hard links created in React/includes',
+    );
+  } catch (error) {
+    throw new Error(`Hard link creation failed: ${error.message}`);
+  }
+}
+
 module.exports = {
   findXcodeProjectDirectory,
   runPodDeintegrate,
   runIosPrebuild,
   configureAppForSwift,
   setBuildFromSource,
+  createHardlinks,
 };