Move babel config to a separate file in static directory

build/Gruntfile.coffee

@@ -3,7 +3,7 @@ path = require 'path'
 os = require 'os'
 glob = require 'glob'
 usesBabel = require './lib/uses-babel'
-babelOptions = require('../src/babel').defaultOptions
+babelOptions = require('../static/babelrc.json')
 
 # Add support for obselete APIs of vm module so we can make some third-party
 # modules work under node v0.11.x.

src/babel.js

@@ -7,26 +7,7 @@ const path = require('path')
 let babel = null
 let babelVersionDirectory = null
 
-// This field is used by the Gruntfile for compiling babel in bundled packages.
-exports.defaultOptions = {
-
-  // Currently, the cache key is a function of:
-  // * The version of Babel used to transpile the .js file.
-  // * The contents of this defaultOptions object.
-  // * The contents of the .js file.
-  // That means that we cannot allow information from an unknown source
-  // to affect the cache key for the output of transpilation, which means
-  // we cannot allow users to override these default options via a .babelrc
-  // file, because the contents of that .babelrc file will not make it into
-  // the cache key. It would be great to support .babelrc files once we
-  // have a way to do so that is safe with respect to caching.
-  breakConfig: true,
-
-  sourceMap: 'inline',
-  blacklist: ['es6.forOf', 'useStrict'],
-  optional: ['asyncToGenerator'],
-  stage: 0
-}
+const defaultOptions = require('../static/babelrc.json')
 
 exports.shouldCompile = function(sourceCode) {
   return sourceCode.startsWith('/** use babel */') ||

static/babelrc.json

@@ -0,0 +1,7 @@
+{
+  "breakConfig": true,
+  "sourceMap": "inline",
+  "blacklist": ["es6.forOf", "useStrict"],
+  "optional": ["asyncToGenerator"],
+  "stage": 0
+}