@happy-kitchen-89482 @witty-crayon-22786 I remembered why partition-by-config is a thing, and why it didn't "just work" today. Most tools assume a singular config. They load it relative to CWD, or up the chain from first file arg. So if you have one at top level, it'll ignore sub configs. I think ruff uses multi config correctly, but I know for a fact black doesn't.

I think Pants identifies all the files that could be config for the tool on the given set of inputs and puts them in the sandbox. After that it's up to the tool. So I think you should get the same behavior with or without Pants, no?

Yes, but the idea is to partition so you get what you expect, which is hierarchical configuration, even if the tool doesn't support it

Oh, so that would be a new feature

Yes exactly!