sdist/setup errors on unused/referenced cabal files.

[markhibberd]

This is very much an edge case, but there exists Setup.hs files that have environmental dependencies that means that sdist can't run cleanly.

I have a situation where I have a submodule that services multiple dependencies, I need some of those dependencies (non-haskell), but this submodule has one of these not-working-out-of-the-box cabal files. And even though I don't need it / or care about it, it prevents my project from building just because it exists.

Not sure of the best thing to do here. For the time being I am going to try to make it so the Setup.hs doesn't fail, but being able to exclude cabal files somehow might help this.

Low/non-priority given it really should be a non-problem, would just be nice to have a work around.

[thumphries]

sdist also fails on irrelevant submodules sometimes when you hop cabal-install versions. it'd be nice if mafia just logged it and plowed on, let the solver fail instead