Trailing whitespace in generated cabal file

[danielcompton]

When creating a new cabal file with cabal init, there is trailing whitespace created on lines that are commented out. These should be trimmed before the file is created.

[23Skidoo]

I looked into this, and it seems to be caused by the pretty-printing library.

/cc @byorgey

[mpickering]

Would also like to see this fixed, how difficult would it be for a cabal newbie to take on?

[23Skidoo]

@mpickering cabal init is a pretty self-contained part of cabal-install. Look at cabal-install/Distribution/Client/Init.hs. The problem is caused by the pretty-printing library, though, so maybe the issue can be fixed by switching to e.g. pretty-compact.

[ttuegel]

This seems to be a duplicate of #1966.