note a few more changes

Conflicts:
	encoding.cabal

.gitignore

@@ -0,0 +1,22 @@
+### Haskell ###
+dist
+dist-*
+cabal-dev
+*.o
+*.hi
+*.chi
+*.chs.h
+*.dyn_o
+*.dyn_hi
+.hpc
+.hsenv
+.cabal-sandbox/
+cabal.sandbox.config
+*.prof
+*.aux
+*.hp
+*.eventlog
+.stack-work/
+cabal.project.local
+.HTF/
+

CHANGELOG

@@ -1,3 +1,36 @@
+Changes from 0.8 to 0.8.2
+-------------------------
+
+* Deprecated support for very old GHCs
+* Updated cabal file to differentiate between build dependencies and setup dependencies
+* Add upper and lower bounds to build dependencies
+* Stack compatibility
+
+Changes from 0.8 to 0.8.1
+-------------------------
+
+* Added the ShiftJIS and CP932 encodings
+
+Changes from 0.7.0.2 to 0.8
+---------------------------
+
+* GHC-7.10/AMP compatibility
+
+Changes from 0.7.0.1 to 0.7.0.2
+-------------------------------
+
+* Flesh out the MacOSRoman encoding, which was missing 33 code points
+
+Changes from 0.7 to 0.7.0.1
+---------------------------
+
+* GHC-7.8 compatibility
+
+Changes from 0.6.7 to 0.7
+-------------------------
+
+* the type of ByteSource's fetchAhead method changed to accomodate updates to the binary package
+
 Changes from 0.6.5 to 0.6.7
 ---------------------------
 

Data/Array/Static.hs

@@ -1,4 +1,4 @@
-{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE MagicHash,BangPatterns #-}
 module Data.Array.Static where
 
 import Data.Static
@@ -11,5 +11,5 @@ bounds :: Ix i => StaticArray i e -> (i,i)
 bounds (StaticArray s e _) = (s,e)
 
 (!) :: (StaticElement e,Ix i) => StaticArray i e -> i -> e
-(!) (StaticArray s e addr) i = let (I# ri) = index (s,e) i
+(!) (StaticArray s e addr) i = let !(I# ri) = index (s,e) i
                                in extract addr ri

Data/Encoding.hs

@@ -76,6 +76,7 @@ import Data.Encoding.MacOSRoman
 import Data.Encoding.JISX0201
 import Data.Encoding.JISX0208
 import Data.Encoding.ISO2022JP
+import Data.Encoding.ShiftJIS
 import Data.Encoding.CP437
 import Data.Encoding.CP737
 import Data.Encoding.CP775
@@ -92,6 +93,7 @@ import Data.Encoding.CP865
 import Data.Encoding.CP866
 import Data.Encoding.CP869
 import Data.Encoding.CP874
+import Data.Encoding.CP932
 import Data.Char
 import Text.Regex
 
@@ -327,6 +329,9 @@ encodingFromStringExplicit codeName = case (normalizeEncoding codeName) of
     "jis_x_0208"         -> Just $ DynEncoding JISX0208
     -- ISO 2022-JP
     "iso_2022_jp"        -> Just $ DynEncoding ISO2022JP
+    -- Shift JIS
+    "shift_jis"          -> Just $ DynEncoding ShiftJIS
+    "sjis"               -> Just $ DynEncoding ShiftJIS
     -- MSDOS codepages
     "cp437"              -> Just $ DynEncoding CP437
     "cp737"              -> Just $ DynEncoding CP737
@@ -344,6 +349,7 @@ encodingFromStringExplicit codeName = case (normalizeEncoding codeName) of
     "cp866"              -> Just $ DynEncoding CP866
     "cp869"              -> Just $ DynEncoding CP869
     "cp874"              -> Just $ DynEncoding CP874
+    "cp932"              -> Just $ DynEncoding CP932
     -- defaults to nothing
     _                    -> Nothing
   where

Data/Encoding/ByteSink.hs

@@ -11,6 +11,7 @@ import Data.Word
 import Data.Foldable (toList)
 import Control.Throws
 import Control.Exception.Extensible
+import Control.Applicative
 import Control.Monad.State
 import Control.Monad.Identity
 import Control.Monad.Reader
@@ -80,6 +81,13 @@ instance ByteSink PutM where
 
 newtype PutME a = PutME (Either EncodingException (PutM (),a))
 
+instance Functor PutME where
+  fmap = liftM
+
+instance Applicative PutME where
+  pure = return
+  (<*>) = ap
+
 instance Monad PutME where
     return x = PutME $ Right (return (),x)
     (PutME x) >>= g = PutME $ do
@@ -114,6 +122,13 @@ instance (Monad m,Throws EncodingException m) => ByteSink (StateT (Seq Char) m)
 
 newtype StrictSink a = StrictS (Ptr Word8 -> Int -> Int -> IO (a,Ptr Word8,Int,Int))
 
+instance Functor StrictSink where
+  fmap = liftM
+
+instance Applicative StrictSink where
+  pure = return
+  (<*>) = ap
+
 instance Monad StrictSink where
     return x = StrictS $ \cstr pos max -> return (x,cstr,pos,max)
     (StrictS f) >>= g = StrictS (\cstr pos max -> do
@@ -140,6 +155,13 @@ instance ByteSink StrictSink where
 
 newtype StrictSinkE a = StrictSinkE (StrictSink (Either EncodingException a))
 
+instance Functor StrictSinkE where
+  fmap = liftM
+
+instance Applicative StrictSinkE where
+  pure = return
+  (<*>) = ap
+
 instance Monad StrictSinkE where
     return = StrictSinkE . return . Right
     (StrictSinkE s) >>= g = StrictSinkE $ do
@@ -167,6 +189,13 @@ createStrict sink = createStrictWithLen sink 32
 
 newtype StrictSinkExplicit a = StrictSinkExplicit  (StrictSink (Either EncodingException a))
 
+instance Functor StrictSinkExplicit where
+  fmap = liftM
+
+instance Applicative StrictSinkExplicit where
+  pure = return
+  (<*>) = ap
+
 instance Monad StrictSinkExplicit where
     return = (StrictSinkExplicit).return.Right
     (StrictSinkExplicit sink) >>= f

Data/Encoding/ByteSource.hs

@@ -6,7 +6,9 @@ import Data.Encoding.Exception
 import Data.Bits
 import Data.Binary.Get
 import Data.Char
+import Data.Maybe
 import Data.Word
+import Control.Applicative as A
 import Control.Monad.State
 import Control.Monad.Identity
 import Control.Monad.Reader
@@ -19,7 +21,9 @@ import System.IO
 class (Monad m,Throws DecodingException m) => ByteSource m where
     sourceEmpty :: m Bool
     fetchWord8 :: m Word8
-    fetchAhead :: m a -> m a
+    -- 'fetchAhead act' should return the same thing 'act' does, but should
+    -- only consume input if 'act' returns a 'Just' value
+    fetchAhead :: m (Maybe a) -> m (Maybe a)
     fetchWord16be :: m Word16
     fetchWord16be = do
       w1 <- fetchWord8
@@ -95,7 +99,20 @@ instance Throws DecodingException Get where
 instance ByteSource Get where
     sourceEmpty = isEmpty
     fetchWord8 = getWord8
-    fetchAhead = lookAhead
+#if MIN_VERSION_binary(0,6,0)
+    fetchAhead act = (do
+        res <- act
+        case res of
+            Nothing -> A.empty
+            Just a  -> return res
+        ) <|> return Nothing
+#else
+    fetchAhead act = do
+        res <- lookAhead act
+        case res of
+            Nothing -> return Nothing
+            Just a  -> act
+#endif
     fetchWord16be = getWord16be
     fetchWord16le = getWord16le
     fetchWord32be = getWord32be
@@ -103,20 +120,22 @@ instance ByteSource Get where
     fetchWord64be = getWord64be
     fetchWord64le = getWord64le
 
+fetchAheadState act = do
+    chs <- get
+    res <- act
+    when (isNothing res) (put chs)
+    return res
+
 instance ByteSource (StateT [Char] Identity) where
     sourceEmpty = gets null
     fetchWord8 = do
       chs <- get
       case chs of
-        [] -> throw UnexpectedEnd
+        [] -> throwException UnexpectedEnd
         c:cs -> do
           put cs
           return (fromIntegral $ ord c)
-    fetchAhead act = do
-      chs <- get
-      res <- act
-      put chs
-      return res
+    fetchAhead = fetchAheadState
 
 #if MIN_VERSION_base(4,3,0)
 #else
@@ -135,33 +154,21 @@ instance ByteSource (StateT [Char] (Either DecodingException)) where
         c:cs -> do
           put cs
           return (fromIntegral $ ord c)
-    fetchAhead act = do
-      chs <- get
-      res <- act
-      put chs
-      return res
+    fetchAhead = fetchAheadState
 
 instance (Monad m,Throws DecodingException m) => ByteSource (StateT BS.ByteString m) where
     sourceEmpty = gets BS.null
     fetchWord8 = StateT (\str -> case BS.uncons str of
-                                  Nothing -> throw UnexpectedEnd
+                                  Nothing -> throwException UnexpectedEnd
                                   Just (c,cs) -> return (c,cs))
-    fetchAhead act = do
-      str <- get
-      res <- act
-      put str
-      return res
+    fetchAhead = fetchAheadState
 
 instance ByteSource (StateT LBS.ByteString (Either DecodingException)) where
     sourceEmpty = gets LBS.null
     fetchWord8 = StateT (\str -> case LBS.uncons str of
                                   Nothing -> Left UnexpectedEnd
                                   Just ns -> Right ns)
-    fetchAhead act = do
-      chs <- get
-      res <- act
-      put chs
-      return res
+    fetchAhead = fetchAheadState
 
 instance ByteSource (ReaderT Handle IO) where
     sourceEmpty = do
@@ -176,5 +183,5 @@ instance ByteSource (ReaderT Handle IO) where
       h <- ask
       pos <- liftIO $ hGetPosn h
       res <- act
-      liftIO $ hSetPosn pos
+      when (isNothing res) (liftIO $ hSetPosn pos)
       return res

Data/Encoding/Exception.hs

@@ -11,7 +11,7 @@ import Control.Monad.Identity
 data EncodingException
     = HasNoRepresentation Char	-- ^ Thrown if a specific character
 				--   is not representable in an encoding.
-    deriving (Eq,Show,Typeable)
+    deriving (Eq,Ord,Show,Read,Typeable)
 
 instance Exception EncodingException
 
@@ -25,6 +25,6 @@ data DecodingException
     | OutOfRange		-- ^ the decoded value was out of the unicode range
     | IllegalRepresentation [Word8]	-- ^ The character sequence encodes a
 					--   character, but is illegal.
-    deriving (Eq,Show,Typeable)
+    deriving (Eq,Ord,Show,Read,Typeable)
 
 instance Exception DecodingException

Data/Encoding/ISO2022JP.hs

@@ -26,11 +26,10 @@ instance Encoding ISO2022JP where
     encodeable _ c = encodeable ASCII c || encodeable JISX0201 c || encodeable JISX0208 c
 
 instance ISO2022 ISO2022JP where
-    readEscape _ = do
-      w <- fetchAhead fetchWord8
+    readEscape _ = fetchAhead $ do
+      w <- fetchWord8
       if w == 27
         then (do
-               fetchWord8
                w2 <- fetchWord8
                w3 <- fetchWord8
                case w2 of

Data/Encoding/MacOSRoman.mapping

@@ -61,6 +61,38 @@
 #   * Change mapping of 0xBD from U+2126 to its canonical
 #     decomposition, U+03A9.
 
+0x00	0x0000	# NULL
+0x01	0x0001	# START OF HEADING
+0x02	0x0002	# START OF TEXT
+0x03	0x0003	# END OF TEXT
+0x04	0x0004	# END OF TRANSMISSION
+0x05	0x0005	# ENQUIRY
+0x06	0x0006	# ACKNOWLEDGE
+0x07	0x0007	# BELL
+0x08	0x0008	# BACKSPACE
+0x09	0x0009	# HORIZONTAL TABULATION
+0x0A	0x000A	# LINE FEED
+0x0B	0x000B	# VERTICAL TABULATION
+0x0C	0x000C	# FORM FEED
+0x0D	0x000D	# CARRIAGE RETURN
+0x0E	0x000E	# SHIFT OUT
+0x0F	0x000F	# SHIFT IN
+0x10	0x0010	# DATA LINK ESCAPE
+0x11	0x0011	# DEVICE CONTROL ONE
+0x12	0x0012	# DEVICE CONTROL TWO
+0x13	0x0013	# DEVICE CONTROL THREE
+0x14	0x0014	# DEVICE CONTROL FOUR
+0x15	0x0015	# NEGATIVE ACKNOWLEDGE
+0x16	0x0016	# SYNCHRONOUS IDLE
+0x17	0x0017	# END OF TRANSMISSION BLOCK
+0x18	0x0018	# CANCEL
+0x19	0x0019	# END OF MEDIUM
+0x1A	0x001A	# SUBSTITUTE
+0x1B	0x001B	# ESCAPE
+0x1C	0x001C	# FILE SEPARATOR
+0x1D	0x001D	# GROUP SEPARATOR
+0x1E	0x001E	# RECORD SEPARATOR
+0x1F	0x001F	# UNIT SEPARATOR
 0x20	0x0020	# SPACE
 0x21	0x0021	# EXCLAMATION MARK
 0x22	0x0022	# QUOTATION MARK
@@ -156,7 +188,7 @@
 0x7C	0x007C	# VERTICAL LINE
 0x7D	0x007D	# RIGHT CURLY BRACKET
 0x7E	0x007E	# TILDE
-#
+0x7F	0x007F	# DELETE
 0x80	0x00C4	# LATIN CAPITAL LETTER A WITH DIAERESIS
 0x81	0x00C5	# LATIN CAPITAL LETTER A WITH RING ABOVE
 0x82	0x00C7	# LATIN CAPITAL LETTER C WITH CEDILLA

Data/Static.hs

@@ -1,4 +1,4 @@
-{-# LANGUAGE MagicHash,FlexibleInstances,BangPatterns #-}
+{-# LANGUAGE MagicHash,FlexibleInstances,BangPatterns,CPP #-}
 module Data.Static where
 
 import GHC.Exts
@@ -36,7 +36,11 @@ instance StaticElement Char where
 
 instance StaticElement (Maybe Char) where
     extract addr i = let !v = indexWord32OffAddr# addr i
+#if __GLASGOW_HASKELL__ >= 708
+                     in if isTrue# (eqWord# v (int2Word# 4294967295#)) -- -1 in Word32
+#else
                      in if eqWord# v (int2Word# 4294967295#) -- -1 in Word32
+#endif
                         then Nothing
                         else (if (I# (word2Int# v)) > 0x10FFFF
                               then error (show (I# (word2Int# v))++" is not a valid char ("++show (I# i)++")")

RELEASING

@@ -1,5 +1,5 @@
 On each release:
-* update NEWS
+* update CHANGELOG
 * bump the version number in the .cabal file (including in the "this" repository spec)
 * cabal upload a release tarball
 * darcs tag with the version number
@@ -9,7 +9,6 @@ cabal configure
 ./dist/setup/setup sdist
 tar xf dist/encoding-version.tar.gz
 rm -r encoding-version/dist
-tar cf dist/encoding-version.tar encoding-version
+tar --format=ustar -czf dist/encoding-version.tar.gz encoding-version
 rm -r encoding-version
-gzip -f dist/encoding-version.tar
 cabal upload dist/encoding-version.tar

encoding.cabal

@@ -1,18 +1,18 @@
 Name:		encoding
-Version:	0.6.7.1
+Version:	0.8.2
 Author:		Henning Günther
 Maintainer:	daniel@wagner-home.com
 License:	BSD3
 License-File:   LICENSE
 Synopsis:	A library for various character encodings
 Description:
-	Haskell has excellect handling of unicode, the Char type covers all unicode chars. Unfortunatly, there's no possibility to read or write something to the outer world in an encoding other than ascii due to the lack of support for encodings. This library should help with that.
+	Haskell has excellect handling of unicode, the Char type covers all unicode chars. Unfortunately, there's no possibility to read or write something to the outer world in an encoding other than ascii due to the lack of support for encodings. This library should help with that.
 Category:	Codec
 Homepage:	http://code.haskell.org/encoding/
-Cabal-Version:	>=1.6
+Cabal-Version:	>=1.8
 Build-Type:	Custom
 Extra-Source-Files:
-  NEWS
+  CHANGELOG
   Data/Encoding/Preprocessor/Mapping.hs
   Data/Encoding/Preprocessor/XMLMapping.hs
   Data/Encoding/Preprocessor/XMLMappingBuilder.hs
@@ -22,32 +22,36 @@ Extra-Source-Files:
   system_encoding.h
   system_encoding.c
 
-Flag splitBase
-  description:	Choose the new smaller, split-up base package.
-Flag newGHC
-  description: Use ghc version > 6.10
 Flag systemEncoding
   description: Provide the getSystemEncoding action to query the locale.
 
 Source-Repository head
-  Type:			darcs
-  Location:		http://code.haskell.org/encoding
+  Type:         git
+  Location:     http://github.com/dmwit/encoding
 
 Source-Repository this
-  Type:			darcs
-  Location:		http://code.haskell.org/encoding
-  Tag:			0.6.7.1
+  Type:         git
+  Location:     http://github.com/dmwit/encoding
+  Tag:          0.8.2
+
+Custom-Setup
+  Setup-Depends: base >=3 && <5,
+                 Cabal >=1.24 && <1.25,
+                 containers,
+                 filepath,
+                 ghc-prim,
+                 HaXml >=1.22 && <1.26
 
 Library
-  Build-Depends:	binary, extensible-exceptions, HaXml >= 1.22 && < 1.24
-  if flag(splitBase)
-    Build-Depends:	bytestring, base >= 3 && < 5, mtl, containers, array, regex-compat
-    if flag(newGHC)
-      Build-Depends:	ghc-prim, ghc >= 6.10
-    else
-      Build-Depends:	ghc < 6.10
-  else
-    Build-Depends:	base < 3
+  Build-Depends: array >=0.4 && <0.6,
+                 base >=4 && <5,
+                 binary >=0.7 && <0.10,
+                 bytestring >=0.9 && <0.11,
+                 containers >=0.4 && <0.6,
+                 extensible-exceptions >=0.1 && <0.2,
+                 ghc-prim >=0.3 && <0.6,
+                 mtl >=2.0 && <2.3,
+                 regex-compat >=0.71 && <0.95
 
   Extensions: CPP
 
@@ -95,6 +99,7 @@ Library
     Data.Encoding.JISX0212
     Data.Encoding.ISO2022
     Data.Encoding.ISO2022JP
+    Data.Encoding.ShiftJIS
     Data.Encoding.CP437
     Data.Encoding.CP737
     Data.Encoding.CP775
@@ -111,6 +116,7 @@ Library
     Data.Encoding.CP866
     Data.Encoding.CP869
     Data.Encoding.CP874
+    Data.Encoding.CP932
     System.IO.Encoding
   Other-Modules:
     Data.Encoding.Base
@@ -118,6 +124,8 @@ Library
     Data.Map.Static
     Data.Static
     Data.CharMap
+  if impl(ghc >= 7.10)
+    GHC-Options: -fno-warn-tabs
   if flag(systemEncoding)
     Includes:
       system_encoding.h
@@ -126,3 +134,16 @@ Library
     C-Sources:
       system_encoding.c
     CPP-Options: -DSYSTEM_ENCODING
+
+test-suite encoding-test
+  type:                exitcode-stdio-1.0
+  hs-source-dirs:      tests
+  main-is:             Main.hs
+  other-modules:       Test.Tester
+                     , Test.Tests
+  build-depends:       base
+                     , bytestring
+                     , encoding
+                     , HUnit
+                     , QuickCheck
+  ghc-options:         -threaded -rtsopts -with-rtsopts=-N

stack.yaml

@@ -0,0 +1,66 @@
+# This file was automatically generated by 'stack init'
+#
+# Some commonly used options have been documented as comments in this file.
+# For advanced use and comprehensive documentation of the format, please see:
+# http://docs.haskellstack.org/en/stable/yaml_configuration/
+
+# Resolver to choose a 'specific' stackage snapshot or a compiler version.
+# A snapshot resolver dictates the compiler version and the set of packages
+# to be used for project dependencies. For example:
+#
+# resolver: lts-3.5
+# resolver: nightly-2015-09-21
+# resolver: ghc-7.10.2
+# resolver: ghcjs-0.1.0_ghc-7.10.2
+# resolver:
+#  name: custom-snapshot
+#  location: "./custom-snapshot.yaml"
+resolver: lts-8.22
+
+# User packages to be built.
+# Various formats can be used as shown in the example below.
+#
+# packages:
+# - some-directory
+# - https://example.com/foo/bar/baz-0.0.2.tar.gz
+# - location:
+#    git: https://github.com/commercialhaskell/stack.git
+#    commit: e7b331f14bcffb8367cd58fbfc8b40ec7642100a
+# - location: https://github.com/commercialhaskell/stack/commit/e7b331f14bcffb8367cd58fbfc8b40ec7642100a
+#   extra-dep: true
+#  subdirs:
+#  - auto-update
+#  - wai
+#
+# A package marked 'extra-dep: true' will only be built if demanded by a
+# non-dependency (i.e. a user package), and its test suites and benchmarks
+# will not be run. This is useful for tweaking upstream packages.
+packages:
+- '.'
+# Dependency packages to be pulled from upstream that are not in the resolver
+# (e.g., acme-missiles-0.3)
+extra-deps: []
+
+# Override default flag values for local packages and extra-deps
+flags: {}
+
+# Extra package databases containing global packages
+extra-package-dbs: []
+
+# Control whether we use the GHC we find on the path
+# system-ghc: true
+#
+# Require a specific version of stack, using version ranges
+# require-stack-version: -any # Default
+# require-stack-version: ">=1.4"
+#
+# Override the architecture used by stack, especially useful on Windows
+# arch: i386
+# arch: x86_64
+#
+# Extra directories used by stack for building
+# extra-include-dirs: [/path/to/dir]
+# extra-lib-dirs: [/path/to/dir]
+#
+# Allow a newer minor version of GHC than the snapshot specifies
+# compiler-check: newer-minor

tests/Main.hs

@@ -0,0 +1,18 @@
+import Control.Monad
+import Test.HUnit
+import Test.Tests
+
+hunitTests =
+	[ ("utf8Tests", utf8Tests)
+	, ("utf16Tests", utf16Tests)
+	, ("punycodeTests", punycodeTests)
+	, ("isoTests", isoTests)
+	, ("jisTests", jisTests)
+	, ("gb18030Tests", gb18030Tests)
+	]
+
+main = do
+	identityTests
+	forM_ hunitTests $ \(name, test) -> do
+		putStrLn $ "running " ++ name
+		runTestTT test >>= print

tests/RegressionTest.hs

@@ -0,0 +1,66 @@
+{-# LANGUAGE NoMonomorphismRestriction #-}
+import Control.Applicative
+import Control.Monad
+import Data.ByteString (ByteString, pack)
+import Data.Encoding
+import Data.Word
+import System.Random
+
+-- for example:
+import Data.Encoding.ISO2022JP
+--main = generate ISO2022JP
+main = test ISO2022JP
+-- BEWARE! These things are _very_ memory-hungry if you don't compile with optimizations.
+-- end example
+
+randomRepeat f max = randomRIO (0, max) >>= flip replicateM f
+randomString = randomRepeat randomIO
+randomGoodString = randomRepeat . randomGoodChar
+randomGoodChar f = let
+	good = filter f [minBound..maxBound]
+	n    = length good
+	in do
+	i <- randomRIO (0, n-1)
+	return (good !! i)
+
+generate enc = do
+	let filename = show enc ++ ".regression"
+	    randomGood = randomGoodString (encodeable enc)
+	shortMixedEnc <- replicateM  300 (         randomString   10)
+	shortGoodEnc  <- replicateM   30 (         randomGood     10)
+	longMixedEnc  <- replicateM  300 (         randomString 1000)
+	longGoodEnc   <- replicateM 3000 (         randomGood   1000)
+	shortDec      <- replicateM  300 (pack <$> randomString   10)
+	longDec       <- replicateM 3000 (pack <$> randomString 1000)
+	writeFile filename (show
+		[ (s, encodeStrictByteStringExplicit enc s)
+		| ss <- [shortMixedEnc, shortGoodEnc, longMixedEnc, longGoodEnc]
+		, s <- ss
+		] ++ "\n")
+	appendFile filename (show
+		[ (bs, decodeStrictByteStringExplicit enc bs)
+		| bss <- [shortDec, longDec]
+		, bs <- bss
+		] ++ "\n")
+
+complain action input expected actual = when (expected /= actual) . putStrLn . concat $
+	[ "when "
+	, pad action
+	, show input
+	, "\n"
+	, pad "expected"
+	, show expected
+	, "\n"
+	, pad "but got"
+	, show actual
+	]
+	where
+	size  = maximum . map length $ [action, "expected", "but got"]
+	pad s = s ++ replicate (size - length s) ' ' ++ ": "
+
+test enc = do
+	[encoded_, decoded_] <- lines <$> readFile (show enc ++ ".regression")
+	let encoded = read encoded_
+	    decoded = read decoded_
+	forM_ encoded $ \(s , correctEncoding) -> complain "encoding"  s correctEncoding (encodeStrictByteStringExplicit enc  s)
+	forM_ decoded $ \(bs, correctDecoding) -> complain "decoding" bs correctDecoding (decodeStrictByteStringExplicit enc bs)

tests/Test/Tester.hs

@@ -53,9 +53,6 @@ charGen = let
     threeByte = choose (0x010000,0x10FFFF) >>= return.chr
     in frequency [(40,ascii),(30,oneByte),(20,twoByte),(10,threeByte)]
 
-instance Arbitrary Word8 where
-    arbitrary = choose (0x00,0xFF::Int) >>= return.fromIntegral
-
 quickCheckEncoding :: Encoding enc => enc -> IO ()
 quickCheckEncoding e = do
   quickCheck (encodingIdentity e)