metro/packages/setupBabel.js

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2017-02-27 10:41:38 +00:00
/**
* Copyright (c) 2013-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.
*/
'use strict';
const babelRegisterOnly = require('./metro-bundler/babelRegisterOnly');
const escapeRegExp = require('lodash/escapeRegExp');
const path = require('path');
const BABEL_ENABLED_PATHS = [
'metro-bundler/src',
'metro-bundler/transformer.js',
'metro-bundler/react-packager.js',
];
/**
* We use absolute paths for matching only the top-level folders reliably. For
* example, we would not want to match some deeply nested forder that happens to
* have the same name as one of `BABEL_ENABLED_PATHS`.
*/
function buildRegExps(basePath, dirPaths) {
return dirPaths.map(folderPath =>
// Babel `only` option works with forward slashes in the RegExp so replace
// backslashes for Windows.
new RegExp(`^${escapeRegExp(path.resolve(basePath, folderPath).replace(/\\/g, '/'))}`)
);
}
function getOnlyList() {
return buildRegExps(__dirname, BABEL_ENABLED_PATHS);
}
/**
* Centralized place to register all the directories that need a Babel
* transformation before being fed to Node.js. Notably, this is necessary to
* support Flow type annotations.
*/
function setupBabel() {
babelRegisterOnly(getOnlyList());
}
setupBabel.buildRegExps = buildRegExps;
setupBabel.getOnlyList = getOnlyList;
module.exports = setupBabel;