Get source map from server about css

[conradz]

I don't think we can do this without majorly changing the API to make it async, since I don't know that there is any way to synchronously make HTTP requests. You could specify inputSourcemaps: false when stringifying and then manually process the source map object afterwards.

[lydell]

That’s why I don’t think that compilers should deal with previous source maps at all (not even like this module currently works). That’s the job of a separate tool. Every single compiler shouldn’t duplicate the same effort.

[conradz]

I'm starting to think that too, maybe we should just remove that in v3.0? It's really not hard to do at all (and rework itself could automatically do it, just not the css parser/stringifier).

[lydell]

Sounds like a good idea.

[donaldpipowitch]

I thought from looking into source that it would be quite difficult to integrate async logic, too. I know that this is troublesome, but as the source map spec allows serving source maps in that way I kinda expected it to just work.

Creating a separate tool to solve this problem sounds nice. But I wonder... isn't that what https://github.com/mozilla/source-map already does? (Or should do?)

[lydell]

@donaldpipowitch See mozilla/source-map#84.