Resolve regenerator runtime relative to react-scripts (facebook#2175)

Author: gaearon

config/webpack.config.dev.js

@@ -93,6 +93,15 @@ module.exports = {
     // https://github.com/facebookincubator/create-react-app/issues/290
     extensions: ['.js', '.json', '.jsx'],
     alias: {
+      // @remove-on-eject-begin
+      // Resolve Babel runtime relative to react-scripts.
+      // It usually still works on npm 3 without this but it would be
+      // unfortunate to rely on, as react-scripts could be symlinked,
+      // and thus babel-runtime might not be resolvable from the source.
+      'babel-runtime': path.dirname(
+        require.resolve('babel-runtime/package.json')
+      ),
+      // @remove-on-eject-end
       // Support React Native Web
       // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
       'react-native': 'react-native-web',

config/webpack.config.prod.js

@@ -90,6 +90,15 @@ module.exports = {
     // https://github.com/facebookincubator/create-react-app/issues/290
     extensions: ['.js', '.json', '.jsx'],
     alias: {
+      // @remove-on-eject-begin
+      // Resolve Babel runtime relative to react-scripts.
+      // It usually still works on npm 3 without this but it would be
+      // unfortunate to rely on, as react-scripts could be symlinked,
+      // and thus babel-runtime might not be resolvable from the source.
+      'babel-runtime': path.dirname(
+        require.resolve('babel-runtime/package.json')
+      ),
+      // @remove-on-eject-end
       // Support React Native Web
       // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
       'react-native': 'react-native-web',