chore: use react-native init for generating example app

packages/create-react-native-library/src/index.ts

@@ -8,6 +8,7 @@ import spawn from 'cross-spawn';
 import validateNpmPackage from 'validate-npm-package-name';
 import githubUsername from 'github-username';
 import prompts, { PromptObject } from './utils/prompts';
+import generateRNApp from './utils/generateRNApp';
 
 const FALLBACK_BOB_VERSION = '0.18.3';
 
@@ -407,6 +408,15 @@ async function create(argv: yargs.Arguments<any>) {
     }
   };
 
+  await fs.mkdirp(folder);
+  if (options.project.native) {
+    generateRNApp({
+      dest: folder,
+      projectName: options.project.name,
+      isTurboModule: options.project.turbomodule,
+    });
+  }
+
   await copyDir(COMMON_FILES, folder);
 
   if (languages === 'js') {

packages/create-react-native-library/src/utils/generateRNApp.ts

@@ -0,0 +1,127 @@
+import fs from 'fs';
+import spawn from 'cross-spawn';
+import path from 'path';
+
+const FILES_TO_DELETE = [
+  '.eslintrc.js',
+  'tsconfig.json',
+  '.gitignore',
+  '.git',
+  '.prettierrc.js',
+  'index.js',
+  'App.tsx',
+];
+
+const PACKAGES_TO_REMOVE = [
+  '@react-native-community/eslint-config',
+  '@tsconfig/react-native',
+  '@types/jest',
+  '@types/react-native',
+  '@types/react-test-renderer',
+  '@typescript-eslint/eslint-plugin',
+  '@typescript-eslint/parser',
+  'babel-jest',
+  'eslint',
+  'jest',
+  'react-test-renderer',
+  'typescript',
+];
+
+const PACKAGES_TO_ADD = {
+  'babel-plugin-module-resolver': '^4.1.0',
+  'metro-react-native-babel-preset': '^0.72.1',
+  'patch-package': '^6.4.7',
+  'postinstall-postinstall': '^2.1.0',
+};
+
+export default function generateRNApp({
+  dest,
+  projectName,
+  isTurboModule,
+}: {
+  dest: string;
+  projectName: string;
+  isTurboModule: boolean;
+}) {
+  // Generate the example app's base using `npx react-native init <projectName>Example --template react-native-template-typescript --directory example --skip-install --version <version>`
+  const createRNAppProcess = spawn.sync(
+    'npx',
+    [
+      'react-native',
+      'init',
+      `${projectName}Example`,
+      '--template',
+      'react-native-template-typescript',
+      '--directory',
+      path.join(dest, 'example'),
+      '--skip-install',
+    ],
+    {
+      cwd: dest,
+    }
+  );
+  if (createRNAppProcess.error) {
+    throw createRNAppProcess.error;
+  }
+
+  // Remove unnecessary files
+  FILES_TO_DELETE.forEach((file) => {
+    try {
+      fs.unlinkSync(path.join(dest, 'example', file));
+    } catch (e) {
+      // ignore
+    }
+  });
+
+  // Patch the example app's package.json
+  const examplePackageJson = JSON.parse(
+    fs.readFileSync(path.join(dest, 'example', 'package.json'), 'utf8')
+  );
+  examplePackageJson.scripts = {
+    ...examplePackageJson.scripts,
+    test: undefined,
+    lint: undefined,
+
+    pods: 'pod-install --quiet',
+    postinstall: 'patch-package',
+  };
+  PACKAGES_TO_REMOVE.forEach((pkg) => {
+    examplePackageJson.devDependencies[pkg] = undefined;
+  });
+  examplePackageJson.devDependencies = {
+    ...examplePackageJson.devDependencies,
+    ...PACKAGES_TO_ADD,
+  };
+  examplePackageJson.jest = undefined;
+  fs.writeFileSync(
+    path.join(dest, 'example', 'package.json'),
+    JSON.stringify(examplePackageJson, null, 2)
+  );
+
+  // If the library is a TurboModule, enable new arch for IOS and Android
+  if (isTurboModule) {
+    // Android
+    // Change newArchEnabled=false to newArchEnabled=true in example/android/gradle.properties
+    const gradleProperties = fs
+      .readFileSync(
+        path.join(dest, 'example', 'android', 'gradle.properties'),
+        'utf8'
+      )
+      .replace('newArchEnabled=false', 'newArchEnabled=true');
+    fs.writeFileSync(
+      path.join(dest, 'example', 'android', 'gradle.properties'),
+      gradleProperties
+    );
+
+    // IOS
+    // Add ENV['RCT_NEW_ARCH_ENABLED'] = 1 on top of example/ios/Podfile
+    const podfile = fs.readFileSync(
+      path.join(dest, 'example', 'ios', 'Podfile'),
+      'utf8'
+    );
+    fs.writeFileSync(
+      path.join(dest, 'example', 'ios', 'Podfile'),
+      "ENV['RCT_NEW_ARCH_ENABLED'] = '1'\n" + podfile
+    );
+  }
+}