janrain/coup — pull request #3 by AndrewLorente (2014-05-13 18:46:49+00:00)
Title: Don't error out in the package-already-installed case

This fixes an error message of the form

> ERROR: cabal should only install one package, random-1.0.1.1.
> However, cabal says it's going to install these packages:
>
> You may have to remove these packages manually...

This isn't actually an error! As of this patch, you'll see some warnings from cabal and then your build'll proceed normally.