Treat all unknown extensions as resources

I’m getting a bit tired of extending our whitelist like in #665. I think we should have a “catch all” loader that uses file-loader for any unknown extensions.

This makes sense because it’s easy to explain: “if you import something that isn’t JS or CSS, it becomes a part of the build, you get its filename, and can do whatever with it”.

I think @dralletje planned to look into this.

[cesarandreu]

Looking at webpack.config.dev.js, I’m wondering: why use url-loader for audio / video, but file-loader for images? In the scenarios I’m most familiar with, you’d usually do the complete opposite of that: you want essential images, like sprite sheets, to load immediately, but sound and video can wait.

I think this using file-loader for unknown resources is a good default.

[cpojer]

Thanks Dan for sharing my messages to you. Yes, the transform field is meant to be used for this. If you guys are building css-jest and scss-jest and all, I’m happy to support this officially in Jest – this was my long term plan so we can also have style information in JS, just like we do in react-native:

<View
  style={{
    color: 'green',
  }}
/>

etc.