react-native/local-cli/link/android/patches/applyPatch.js

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

const fs = require('fs');

module.exports = function applyPatch(file, patch) {
  fs.writeFileSync(file, fs
    .readFileSync(file, 'utf8')
    .replace(patch.pattern, match => `${match}${patch.patch}`)
  );
};