ignores cabal file

[mwotton]

If I use a module that's defined in two places like Control.Monad.Trans, and specify the package in the cabal file, everything builds fine but ghc-mod check complains. I assume this is because it's not referring to the cabal file, so it doesn't know which packages to add. Is this a feature that's on the roadmap for implementation?

[kazu-yamamoto]

I don't understand this. Please give me a small example.