Emit a "dependency" message or expose dependencies to other tools

[wbinnssmith]

As far as I can tell, postcss modules does not expose a way for other tools to understand which files it used as a dependency. Build tools like Webpack and Parcel can use this information to invalidate internal caches.

Other postcss plugins like postcss-import[0] and postcss-url[1] emit messages of the type "dependency" with a path to the referenced file.

Does postcss modules expose this kind of information? If not, would you be open to emitting similar messages as the other plugins?

Sorry if this is not the appropriate repository to file this, but I thought it might be the best place to emit similar messages. Please let me know if I'm misunderstanding in any way.

[0] https://github.com/postcss/postcss-import/blob/67f4553fd7fa43c9a3320d172e00e0cd6c6ddc46/index.js#L200
[1] https://github.com/postcss/postcss-url/blob/99dde5556f2aa3f76a40015015c0d01c2aa4c00e/src/lib/decl-processor.js#L60