[commit: Cabal] master: Fixed error message when some depedencies couldn't be resolved. Before it used show on Dependency, not showDependency. (9e90e15)

[Ian Lynagh]

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

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/9e90e150a415250be6d398ca1ff03add0d146660

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

commit 9e90e150a415250be6d398ca1ff03add0d146660
Author: bjorn <bjorn at bringert.net>
Date:   Wed Oct 17 19:08:48 2007 +0000

    Fixed error message when some depedencies couldn't be resolved. Before it used show on Dependency, not showDependency.
    Using fail here produces things like:
    cabal: user error (Unresolved dependencies: containers -any, array -any, bytestring >=0.9)
    It would be nice to get rid of the "user error" here.

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

 cabal-install/Hackage/Fetch.hs   |    3 ++-
 cabal-install/Hackage/Info.hs    |    5 +----
 cabal-install/Hackage/Install.hs |    5 +++--
 cabal-install/Hackage/Utils.hs   |    6 ++++++
 4 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/cabal-install/Hackage/Fetch.hs b/cabal-install/Hackage/Fetch.hs
index 3ba17c3..abcb76e 100644
--- a/cabal-install/Hackage/Fetch.hs
+++ b/cabal-install/Hackage/Fetch.hs
@@ -33,6 +33,7 @@ import System.Directory (doesFileExist, createDirectoryIfMissing)
 import Hackage.Types (ConfigFlags (..), UnresolvedDependency (..), Repo(..), PkgInfo, pkgInfoId)
 import Hackage.Config (repoCacheDir, packageFile, packageDir, pkgURL, message)
 import Hackage.Dependency (resolveDependencies, packagesToInstall)
+import Hackage.Utils
 
 import Distribution.Package (showPackageId)
 import Distribution.Simple.Compiler (Compiler)
@@ -126,7 +127,7 @@ fetch :: ConfigFlags -> Compiler -> ProgramConfiguration -> [String] -> [Unresol
 fetch cfg comp conf _globalArgs deps
     = do depTree <- resolveDependencies cfg comp conf deps
          case packagesToInstall depTree of
-           Left missing -> fail $ "Unresolved dependencies: " ++ show missing
+           Left missing -> fail $ "Unresolved dependencies: " ++ showDependencies missing
            Right pkgs   -> do ps <- filterM (fmap not . isFetched cfg) $ map fst pkgs
                               mapM_ (fetchPackage cfg) ps
 
diff --git a/cabal-install/Hackage/Info.hs b/cabal-install/Hackage/Info.hs
index c5bea60..07e3c32 100644
--- a/cabal-install/Hackage/Info.hs
+++ b/cabal-install/Hackage/Info.hs
@@ -16,12 +16,12 @@ import Hackage.Config
 import Hackage.Dependency 
 import Hackage.Fetch
 import Hackage.Types 
+import Hackage.Utils
 
 import Distribution.Package (showPackageId)
 import Distribution.ParseUtils (showDependency)
 import Distribution.Simple.Compiler (Compiler)
 import Distribution.Simple.Program (ProgramConfiguration)
-import Distribution.Version (Dependency)
 
 import Data.List (intersperse, nubBy)
 import Text.Printf (printf)
@@ -62,6 +62,3 @@ infoPkg cfg (Available dep pkg opts deps)
 infoPkg _ (Unavailable dep)
     = do printf "  Requested:    %s\n" (show $ showDependency dep)
          printf "    Not available!\n\n"
-
-showDependencies :: [Dependency] -> String
-showDependencies = concat . intersperse ", " . map (show . showDependency)
diff --git a/cabal-install/Hackage/Install.hs b/cabal-install/Hackage/Install.hs
index 01281df..342aadd 100644
--- a/cabal-install/Hackage/Install.hs
+++ b/cabal-install/Hackage/Install.hs
@@ -29,6 +29,7 @@ import Hackage.Fetch (fetchPackage)
 import Hackage.Tar (extractTarGzFile)
 import Hackage.Types (ConfigFlags(..), UnresolvedDependency(..)
                      , PkgInfo(..))
+import Hackage.Utils
 
 import Distribution.Simple.Compiler (Compiler(..))
 import Distribution.Simple.InstallDirs (InstallDirs(..), absoluteInstallDirs)
@@ -56,7 +57,7 @@ installLocalPackage cfg comp conf globalArgs =
       desc <- readPackageDescription (configVerbose cfg) cabalFile
       resolvedDeps <- resolveDependenciesLocal cfg comp conf desc globalArgs
       case packagesToInstall resolvedDeps of
-        Left missing -> fail $ "Unresolved dependencies: " ++ show missing
+        Left missing -> fail $ "Unresolved dependencies: " ++ showDependencies missing
         Right pkgs   -> installPackages cfg comp globalArgs pkgs
       let pkgId = package (packageDescription desc)
       installUnpackedPkg cfg comp globalArgs pkgId [] Nothing
@@ -65,7 +66,7 @@ installRepoPackages :: ConfigFlags -> Compiler -> ProgramConfiguration -> [Strin
 installRepoPackages cfg comp conf globalArgs deps =
     do resolvedDeps <- resolveDependencies cfg comp conf deps
        case packagesToInstall resolvedDeps of
-         Left missing -> fail $ "Unresolved dependencies: " ++ show missing
+         Left missing -> fail $ "Unresolved dependencies: " ++ showDependencies missing
          Right []     -> message cfg normal "All requested packages already installed. Nothing to do."
          Right pkgs   -> installPackages cfg comp globalArgs pkgs
 
diff --git a/cabal-install/Hackage/Utils.hs b/cabal-install/Hackage/Utils.hs
index 2f28dbf..5a0ee42 100644
--- a/cabal-install/Hackage/Utils.hs
+++ b/cabal-install/Hackage/Utils.hs
@@ -2,10 +2,12 @@ module Hackage.Utils where
 
 import Distribution.Compat.ReadP (ReadP, readP_to_S, pfail, get, look, choice)
 import Distribution.ParseUtils
+import Distribution.Version
 
 import Control.Exception
 import Control.Monad (foldM, guard)
 import Data.Char (isSpace, toLower)
+import Data.List (intersperse)
 import Data.Maybe (listToMaybe)
 import System.IO.Error (isDoesNotExistError)
 import Text.PrettyPrint.HughesPJ (Doc, render, vcat, text, (<>), (<+>))
@@ -79,3 +81,7 @@ stringNoCase this = look >>= scan this
   scan []     _                               = return this
   scan (x:xs) (y:ys) | toLower x == toLower y = get >> scan xs ys
   scan _      _                               = pfail
+
+
+showDependencies :: [Dependency] -> String
+showDependencies = concat . intersperse ", " . map (show . showDependency)