I agree with not sharing `src/`.

[ffm-mo]

I agree with not sharing src/.

I feel like allowing lib.rs and main.rs to be in the same directory has caused a lot of confusion because users may mod something they actually mean to use from the library. If it wasn't so convenient for bin-only packages, I'd be considering deprecating src/main.rs.

Originally posted by @epage in #3826 (comment)