metro/scripts/build.js

/**
 * Copyright (c) 2014, 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.
 */

'use strict';

/**
 * script to build (transpile) files.
 * By default it transpiles all files for all packages and writes them
 * into `build/` directory.
 * Non-js or files matching IGNORE_PATTERN will be copied without transpiling.
 *
 * Example:
 *  node ./scripts/build.js
 *  node ./scripts/build.js /user/c/metro-bundler/packages/metro-abc/src/abc.js
 */

const babel = require('babel-core');
const chalk = require('chalk');
const fs = require('fs');
const getPackages = require('./_getPackages');
const glob = require('glob');
const micromatch = require('micromatch');
const path = require('path');
const spawnSync = require('child_process').spawnSync;

const SRC_DIR = 'src';
const JS_FILES_PATTERN = '**/*.js';
const IGNORE_PATTERN = '**/__tests__/**';
const PACKAGES_DIR = path.resolve(__dirname, '../packages');

const babelOptions = JSON.parse(fs.readFileSync(
  path.resolve(__dirname, '..', '.babelrc'),
  'utf8'
));
babelOptions.babelrc = false;

const fixedWidth = str => {
  const WIDTH = 80;
  const strs = str.match(new RegExp(`(.{1,${WIDTH}})`, 'g'));
  let lastString = strs[strs.length - 1];
  if (lastString.length < WIDTH) {
    lastString += Array(WIDTH - lastString.length).join(chalk.dim('.'));
  }
  return strs.slice(0, -1).concat(lastString).join('\n');
};

function buildPackage(p) {
  const srcDir = path.resolve(p, SRC_DIR);
  const pattern = path.resolve(srcDir, '**/*');
  const files = glob.sync(pattern, {nodir: true});

  process.stdout.write(
    fixedWidth(`${path.basename(p)}\n`)
  );

  files.forEach(file => buildFile(file, true));
  process.stdout.write(`[  ${chalk.green('OK')}  ]\n`);
}

function buildFile(file, silent) {
  const packageName = path.relative(PACKAGES_DIR, file).split(path.sep)[0];
  const packageSrcPath = path.resolve(PACKAGES_DIR, packageName, 'src');
  const packageBuildPath = path.resolve(PACKAGES_DIR, packageName, 'build');
  const relativeToSrcPath = path.relative(packageSrcPath, file);
  const destPath = path.resolve(packageBuildPath, relativeToSrcPath);

  spawnSync('mkdir', ['-p', path.dirname(destPath)]);
  if (micromatch.isMatch(file, IGNORE_PATTERN)) {
    silent || process.stdout.write(
      chalk.dim('  \u2022 ') +
      path.relative(PACKAGES_DIR, file) +
      ' (ignore)\n'
    );
  } else if (!micromatch.isMatch(file, JS_FILES_PATTERN)) {
    fs.createReadStream(file).pipe(fs.createWriteStream(destPath));
    silent || process.stdout.write(
      chalk.red('  \u2022 ') +
      path.relative(PACKAGES_DIR, file) +
      chalk.red(' \u21D2 ') +
      path.relative(PACKAGES_DIR, destPath) +
      ' (copy)' +
      '\n'
    );
  } else {
    const transformed = babel.transformFileSync(file, babelOptions).code;
    spawnSync('mkdir', ['-p', path.dirname(destPath)]);
    fs.writeFileSync(destPath, transformed);
    silent || process.stdout.write(
      chalk.green('  \u2022 ') +
      path.relative(PACKAGES_DIR, file) +
      chalk.green(' \u21D2 ') +
      path.relative(PACKAGES_DIR, destPath) +
      '\n'
    );
  }
}

const files = process.argv.slice(2);

if (files.length) {
  files.forEach(buildFile);
} else {
  process.stdout.write(chalk.bold.inverse('Building packages\n'));
  getPackages().forEach(buildPackage);
  process.stdout.write('\n');
}