Using babel runtime, but still got `ReferenceError: Can't find variable: Promise`

I notice that Promise polyfill should be required.

But the question is, I am already using the babel runtime transformer to transform my code, and I got Object.assign() working just fine. Only new Promise() in whatwg fetch library throw error Can't find variable: Promise.

I am currently using require('es6-promise').polyfill();, and it works fine.

I am wondering why I still need promise polyfill since I am using babel runtime?

[silvenon]

I’m not sure if this is cool, but this is what I did:

{
  test: /\.jsx?$/,
  include: [
    path.resolve(__dirname, "src"), // our source files
    /whatwg-fetch/, // but also the whatwg-fetch module
  ],
  loader: "babel-loader",
},

This way I’m processing whatwg-fetch with Babel as well, so transform-runtime patches its Promise usage.

[silvenon]

import isomorphic-fetch works as well because it requires whatwg-fetch, so it will still get processed by webpack with the above config.