Sourcemaps not applied on processor errors

[emilgoldsmith]

Sourcemaps don't get applied on errors that our processor throws, it's possible that the fix is as easy as us applying source maps to the lines we put in the constructor of the error, as then we can just let Stylelint handle terminating early etc. as errors from our side also mean that the stylelint call wouldn't be able to finish anyway.

I would do it in the way where we make a wrapper ourselves around the CssError we're currently using that applies the sourcemaps, or in some other way have it modularized / automated.

Now that we're talking about errors, I also think that we should be throwing an error here:

stylelint-processor-styled-components/src/index.js

Line 44 in 78d886e

return ''

as it means our processor crashed. We can still call it a CssSyntaxError, but just put in a message that our processor crashed and maybe include the original error message.

[chinesedfan]

If an CssSyntaxError was thrown, it means failed to parse the input file. The line number already points to the original file, which doesn't need to be converted.

And all errors are handled by #211.