Merge remote-tracking branch 'origin/master' into ghc-head

1 files changed, 21 insertions, 6 deletions

diff --git a/haddock-test/src/Test/Haddock/Config.hs b/haddock-test/src/Test/Haddock/Config.hs
index e1e920f2..988636e4 100644
--- a/haddock-test/src/Test/Haddock/Config.hs
+++ b/haddock-test/src/Test/Haddock/Config.hs
@@ -165,11 +165,18 @@ loadConfig ccfg dcfg flags files = do
     cfgEnv <- (:) ("haddock_datadir", dcfgResDir dcfg) <$> getEnvironment
 
     systemHaddockPath <- List.lookup "HADDOCK_PATH" <$> getEnvironment
-    cfgHaddockPath <- case flagsHaddockPath flags <|> systemHaddockPath of
+    haddockOnPath <- findExecutable "haddock"
+
+    let haddock_path = msum [ flagsHaddockPath flags
+                            , systemHaddockPath
+                            , haddockOnPath
+                            ]
+
+    cfgHaddockPath <- case haddock_path of
         Just path -> pure path
-        Nothing -> do
-            hPutStrLn stderr $ "Haddock executable not specified"
-            exitFailure
+        Nothing   -> do
+          hPutStrLn stderr "Haddock executable not found"
+          exitFailure
 
     ghcPath <- init <$> rawSystemStdout normal cfgHaddockPath
         ["--print-ghc-path"]
@@ -186,7 +193,7 @@ loadConfig ccfg dcfg flags files = do
         , baseDependencies ghcPath
         ]
 
-    let cfgHaddockStdOut = fromMaybe "/dev/null" (flagsHaddockStdOut flags)
+    let cfgHaddockStdOut = fromMaybe defaultStdOut (flagsHaddockStdOut flags)
 
     cfgDiffTool <- if FlagNoDiff `elem` flags
         then pure Nothing
@@ -195,7 +202,7 @@ loadConfig ccfg dcfg flags files = do
     let cfgAccept = FlagAccept `elem` flags
 
     let cfgCheckConfig = ccfg
-    let cfgDirConfig = dcfg
+    let cfgDirConfig   = dcfg
 
     return $ Config { .. }
 
@@ -249,6 +256,14 @@ defaultDiffTool =
     isAvailable = liftM isJust . findProgramLocation silent
 
 
+defaultStdOut :: FilePath
+#ifdef mingw32_HOST_OS
+defaultStdOut = "nul"
+#else
+defaultStdOut = "/dev/null"
+#endif
+
+
 processFileArgs :: DirConfig -> [String] -> IO [TestPackage]
 processFileArgs dcfg [] =
     processFileArgs' dcfg . filter isValidEntry =<< getDirectoryContents srcDir