react-native/packager/react-packager/src/ModuleGraph/output/as-plain-bundle.js

A framework for building native apps using React

/**
 * Copyright (c) 2016-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.
 *
 * @flow
 */
'use strict';

const {createIndexMap} = require('./source-map');
const {addModuleIdsToModuleWrapper} = require('./util');

import type {Module} from '../types.flow';
import type {SourceMap} from './source-map';

module.exports = (
  modules: Iterable<Module>,
  filename?: string,
  idForPath: {path: string} => number,
): {code: string, map: SourceMap} => {
  let code = '';
  let line = 0;
  const sections = [];

  for (const module of modules) {
    const {file} = module;
    const moduleCode = file.type === 'module'
      ? addModuleIdsToModuleWrapper(module, idForPath)
      : file.code;

    code += moduleCode + '\n';
    if (file.map) {
      sections.push({
        map: file.map,
        offset: {column: 0, line}
      });
    }
    line += countLines(moduleCode);
  }

  return {code, map: createIndexMap({file: filename, sections})};
};

const reLine = /^/gm;
function countLines(string: string): number {
  //$FlowFixMe This regular expression always matches
  return string.match(reLine).length;
}