8 files changed, 9 insertions, 10 deletions
diff --git a/libraries/base/tests/IO/encoding001.hs b/libraries/base/tests/IO/encoding001.hs
index c92f8a3ef5..df3c5f914c 100644
--- a/libraries/base/tests/IO/encoding001.hs
+++ b/libraries/base/tests/IO/encoding001.hs
@@ -33,7 +33,7 @@ main = do
   hClose h
 
   -- convert the UTF-32BE file into each other encoding
-  forM_ encodings $ \(enc,name) -> do
+  forM_ encodings $ \(enc,name) ->
      when (name /=  "utf32be") $ do
        hin <- openFile (file <.> "utf32be") ReadMode
        hSetEncoding hin utf32be
diff --git a/libraries/base/tests/IO/encoding004.hs b/libraries/base/tests/IO/encoding004.hs
index 62ef5d6a93..ffd76191f3 100644
--- a/libraries/base/tests/IO/encoding004.hs
+++ b/libraries/base/tests/IO/encoding004.hs
@@ -58,8 +58,8 @@ main = forM_ [ ("CP936",  2, "CP936",      Just "CP936-UTF8")  -- Representative
         utf8_bs <- BS.readFile ("encoded-data" </> utf8_file <.> "txt")
         Right expected <- decode utf8 utf8_bs
         Right actual   <- decode enc  bs
-        unless (expected == actual) $ do
-            putStrLn (bsDiff 0 actual expected)
+        unless (expected == actual) $
+          putStrLn (bsDiff 0 actual expected)
 
 forTruncations :: BS.ByteString -> (BS.ByteString -> IO a) -> IO [a]
 forTruncations bs f = forSplits bs $ \before _ -> f before
diff --git a/libraries/base/tests/IO/hClose002.hs b/libraries/base/tests/IO/hClose002.hs
index ebf26b4663..20eb0f888a 100644
--- a/libraries/base/tests/IO/hClose002.hs
+++ b/libraries/base/tests/IO/hClose002.hs
@@ -27,6 +27,6 @@ showPossibleException f = do e <- try f
                              print (e :: Either SomeException ())
 
 naughtyClose h = 
-  withHandle_ "naughtyClose" h $ \ Handle__{haDevice=dev} -> do
+  withHandle_ "naughtyClose" h $ \ Handle__{haDevice=dev} ->
      IODevice.close dev
 
diff --git a/libraries/base/tests/IO/hClose003.hs b/libraries/base/tests/IO/hClose003.hs
index cbaf49d6db..6d962fd94e 100644
--- a/libraries/base/tests/IO/hClose003.hs
+++ b/libraries/base/tests/IO/hClose003.hs
@@ -38,5 +38,5 @@ showPossibleException f = do
   sanitise' (x:xs) = if isDigit x then (sanitise' xs) else (x:(sanitise xs))
 
 naughtyClose h = 
-  withHandle_ "naughtyClose" h $ \ Handle__{haDevice=dev} -> do
+  withHandle_ "naughtyClose" h $ \ Handle__{haDevice=dev} ->
      IODevice.close dev
diff --git a/libraries/base/tests/IO/hDuplicateTo001.hs b/libraries/base/tests/IO/hDuplicateTo001.hs
index 99f956a0df..e286235e14 100644
--- a/libraries/base/tests/IO/hDuplicateTo001.hs
+++ b/libraries/base/tests/IO/hDuplicateTo001.hs
@@ -18,7 +18,7 @@ main = do
    putStrLn "bla"
 
 
-getfd h@(FileHandle _ mvar) = do
+getfd h@(FileHandle _ mvar) =
   withMVar mvar $ \h__@Handle__{haDevice=dev} ->
    case cast dev of
      Just fd -> return (FD.fdFD fd)
diff --git a/libraries/base/tests/IO/hReady002.hs b/libraries/base/tests/IO/hReady002.hs
index b8b648065b..b13ef8911e 100644
--- a/libraries/base/tests/IO/hReady002.hs
+++ b/libraries/base/tests/IO/hReady002.hs
@@ -5,6 +5,6 @@ import System.Exit
 
 main = do
   m <- newEmptyMVar
-  forkIO $ do threadDelay 500000; putMVar m Nothing
-  forkIO $ do hReady stdin >>= putMVar m . Just
+  forkIO $ threadDelay 500000 >> putMVar m Nothing
+  forkIO $ hReady stdin >>= putMVar m . Just
   takeMVar m >>= print
diff --git a/libraries/base/tests/IO/newline001.hs b/libraries/base/tests/IO/newline001.hs
index 3da867509f..1c894422a9 100644
--- a/libraries/base/tests/IO/newline001.hs
+++ b/libraries/base/tests/IO/newline001.hs
@@ -101,7 +101,7 @@ testoutput b = do
   check "out2" b (toCRLF content) str
   hClose h
 
-check s b str1 str2 = do
+check s b str1 str2 =
   when (str1 /= str2) $ error ("failed: " ++ s ++ ", " ++ show b ++ '\n':show str1 ++ '\n':show str2)
 
 read_chars :: Handle -> IO String
diff --git a/libraries/base/tests/IO/readwrite002.hs b/libraries/base/tests/IO/readwrite002.hs
index 37c7da39cb..5795525b2c 100644
--- a/libraries/base/tests/IO/readwrite002.hs
+++ b/libraries/base/tests/IO/readwrite002.hs
@@ -29,7 +29,6 @@ main = do
    hSeek cd AbsoluteSeek 0
    hSetBuffering cd LineBuffering
    speak cd  `catchIOError` \ err -> if isEOFError err then putStrLn "\nCaught EOF" else ioError err
-   return ()
    hSeek cd AbsoluteSeek 0
    hSetBuffering cd (BlockBuffering Nothing)
    speak cd  `catchIOError` \ err -> if isEOFError err then putStrLn "\nCaught EOF" else ioError err