Is your feature request related to a problem? Please describe.
I have a composer module containing just a composer.json, and a xxxxx.patch file. I accidentally had "type":"metapackage" in my module's composer.json. When including this module in the project, I got a "file not found" error. Changing the package type made it find the patch file.
Describe the solution you'd like
We should mention this in the documentation, but where? I guess ERRORS.md would be best.
Additional context
I'm happy to do the work, just wanted guidance on where to add the doc.