Move Array<string> to $ReadOnlyArray<string>. Separate polyfill list into a file.

Summary: Move the returned type of `getPolyfills` from a standard `Array` to a read-only one, so that we make sure the array is not modified once created. Also, refactor the list of polyfills included by default to a generic, central file, then require it both from the CLI utils as well as the development server.

Reviewed By: jeanlauliac

Differential Revision: D5406553

fbshipit-source-id: ab980288bb1c625338de469da77dd6fc70bcedbc

local-cli/server/runServer.js

@@ -152,12 +152,12 @@ function getPackagerServer(args, config) {
     blacklistRE: config.getBlacklistRE(),
     cacheVersion: '3',
     extraNodeModules: config.extraNodeModules,
+    getPolyfills: config.getPolyfills,
     getTransformOptions: config.getTransformOptions,
     hasteImpl: config.hasteImpl,
     maxWorkers: args.maxWorkers,
     platforms: defaultPlatforms.concat(args.platforms),
     polyfillModuleNames: config.getPolyfillModuleNames(),
-    getPolyfills: config.getPolyfills,
     postMinifyProcess: config.postMinifyProcess,
     postProcessModules: config.postProcessModules,
     projectRoots: args.projectRoots,

local-cli/util/Config.js

@@ -13,6 +13,7 @@
 const blacklist = require('metro-bundler/src/blacklist');
 const findSymlinksPaths = require('./findSymlinksPaths');
 const fs = require('fs');
+const getPolyfills = require('../../rn-get-polyfills');
 const invariant = require('fbjs/lib/invariant');
 const path = require('path');
 
@@ -94,7 +95,7 @@ export type ConfigT = {
    * An optional list of polyfills to include in the bundle. The list defaults
    * to a set of common polyfills for Number, String, Array, Object...
    */
-  getPolyfills: ({platform: string}) => Array<string>,
+  getPolyfills: ({platform: ?string}) => $ReadOnlyArray<string>,
 
   /**
    * An optional function that can modify the code and source map of bundle
@@ -177,17 +178,7 @@ const Config = {
     getSourceExts: () => [],
     getTransformModulePath: () => require.resolve('metro-bundler/src/transformer.js'),
     getTransformOptions: async () => ({}),
-    getPolyfills: ({platform}) => [
-      require.resolve('../../Libraries/polyfills/Object.es6.js'),
-      require.resolve('../../Libraries/polyfills/console.js'),
-      require.resolve('../../Libraries/polyfills/error-guard.js'),
-      require.resolve('../../Libraries/polyfills/Number.es6.js'),
-      require.resolve('../../Libraries/polyfills/String.prototype.es6.js'),
-      require.resolve('../../Libraries/polyfills/Array.prototype.es6.js'),
-      require.resolve('../../Libraries/polyfills/Array.es6.js'),
-      require.resolve('../../Libraries/polyfills/Object.es7.js'),
-      require.resolve('../../Libraries/polyfills/babelHelpers.js'),
-    ],
+    getPolyfills,
     postMinifyProcess: x => x,
     postProcessModules: modules => modules,
     postProcessModulesForBuck: modules => modules,

package.json

@@ -99,6 +99,7 @@
     "jest-preset.json",
     "jest",
     "lib",
+    "rn-get-polyfills.js",
     "setupBabel.js",
     "Libraries",
     "LICENSE",

rn-cli.config.js

@@ -8,6 +8,8 @@
  */
 'use strict';
 
+const getPolyfills = require('./rn-get-polyfills');
+
 /**
  * This cli config is needed for development purposes, e.g. for running
  * integration tests during local development or on CI services.
@@ -16,4 +18,5 @@ module.exports = {
   extraNodeModules: {
     'react-native': __dirname,
   },
+  getPolyfills,
 };

rn-get-polyfills.js

@@ -0,0 +1,23 @@
+/**
+ * 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';
+
+module.exports = () => [
+  require.resolve('./Libraries/polyfills/Object.es6.js'),
+  require.resolve('./Libraries/polyfills/console.js'),
+  require.resolve('./Libraries/polyfills/error-guard.js'),
+  require.resolve('./Libraries/polyfills/Number.es6.js'),
+  require.resolve('./Libraries/polyfills/String.prototype.es6.js'),
+  require.resolve('./Libraries/polyfills/Array.prototype.es6.js'),
+  require.resolve('./Libraries/polyfills/Array.es6.js'),
+  require.resolve('./Libraries/polyfills/Object.es7.js'),
+  require.resolve('./Libraries/polyfills/babelHelpers.js'),
+];