[Hackage] #331: pkg-config error messages could be better

[Hackage]

#331: pkg-config error messages could be better
----------------------------------+-----------------------------------------
  Reporter:  duncan               |        Owner:         
      Type:  defect               |       Status:  new    
  Priority:  normal               |    Milestone:         
 Component:  Cabal library        |      Version:  1.4.0.1
  Severity:  normal               |     Keywords:         
Difficulty:  very easy (<1 hour)  |   Ghcversion:  6.8.2  
  Platform:                       |  
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 Currently if you `cabal install X11-xft` but don't have the xft
 development package installed you get this during configure:

 {{{
 cabal: The pkg-config package xft is required but it could not be found.
 }}}

 What is not immediately clear is that this is a native package and thus
 not something that `cabal-install` could have gone and fetched. So the
 wording of this message could be improved. Perhaps mentioning both in
 general terms and then specifically. For example saying that the
 development files for xft are not installed and that the user probably can
 and should install a native package that provides it. Specifically it's
 looking for a xft.pc file that pkg-config uses to tell is what compiler
 flags to use to use xft.

 A related problem is that the message is somewhat lost in the noise
 because we print the error to stdout rather than throwing it as an
 exception that we could print in the final summary. This problem is
 particulary bad when we have to have error message cross process
 boundaries, ie when cabal-install invokes a setup program.

-- 
Ticket URL: <http://hackage.haskell.org/trac/hackage/ticket/331>
Hackage <http://haskell.org/cabal/>
Hackage: Cabal and related projects