[commit: Cabal] : Fix the -i dir for compiling Setup.hs when it's the current dir (51e6ab5)

[Ian Lynagh]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/Cabal

On branch  : 

http://hackage.haskell.org/trac/ghc/changeset/51e6ab5cb4ce4b959c82071e4de618073a75ba02

>---------------------------------------------------------------

commit 51e6ab5cb4ce4b959c82071e4de618073a75ba02
Author: Duncan Coutts <duncan at haskell.org>
Date:   Fri Oct 10 23:45:58 2008 +0000

    Fix the -i dir for compiling Setup.hs when it's the current dir
    map "" to "."

>---------------------------------------------------------------

 cabal-install/Distribution/Client/SetupWrapper.hs |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/cabal-install/Distribution/Client/SetupWrapper.hs b/cabal-install/Distribution/Client/SetupWrapper.hs
index 8b7331e..33c1666 100644
--- a/cabal-install/Distribution/Client/SetupWrapper.hs
+++ b/cabal-install/Distribution/Client/SetupWrapper.hs
@@ -170,7 +170,9 @@ externalSetupMethod verbosity options pkg bt mkargs = do
   invokeSetupScript (mkargs cabalLibVersion)
 
   where
-  workingDir       = fromMaybe "" (useWorkingDir options)
+  workingDir       = case fromMaybe "" (useWorkingDir options) of
+                       []  -> "."
+                       dir -> dir
   setupDir         = workingDir </> useDistPref options </> "setup"
   setupVersionFile = setupDir </> "setup" <.> "version"
   setupProgFile    = setupDir </> "setup" <.> exeExtension