cra.js

#!/usr/bin/env node
/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

'use strict';

const fs = require('fs');
const path = require('path');
const cp = require('child_process');

const cleanup = () => {
  console.log('Cleaning up.');
  // Reset changes made to package.json files.
  cp.execSync(`git checkout -- packages/*/package.json`);
  // Uncomment when snapshot testing is enabled by default:
  // rm ./template/src/__snapshots__/App.test.js.snap
};

const handleExit = () => {
  cleanup();
  console.log('Exiting without error.');
  process.exit();
};

const handleError = e => {
  console.error('ERROR! An error was encountered while executing');
  console.error(e);
  cleanup();
  console.log('Exiting with error.');
  process.exit(1);
};

process.on('SIGINT', handleExit);
process.on('uncaughtException', handleError);

console.log();
console.log('-------------------------------------------------------');
console.log('Assuming you have already run `yarn` to update the deps.');
console.log('If not, remember to do this before testing!');
console.log('-------------------------------------------------------');
console.log();

// Temporarily overwrite package.json of all packages in monorepo
// to point to each other using absolute file:/ URLs.

const gitStatus = cp.execSync(`git status --porcelain`).toString();

if (gitStatus.trim() !== '') {
  console.log('Please commit your changes before running this script!');
  console.log('Exiting because `git status` is not empty:');
  console.log();
  console.log(gitStatus);
  console.log();
  process.exit(1);
}

const rootDir = path.join(__dirname, '..');
const packagesDir = path.join(rootDir, 'packages');
const packagePathsByName = {};
fs.readdirSync(packagesDir).forEach(name => {
  const packageDir = path.join(packagesDir, name);
  const packageJson = path.join(packageDir, 'package.json');
  if (fs.existsSync(packageJson)) {
    packagePathsByName[name] = packageDir;
  }
});