clean up

5 files changed, 173 insertions, 130 deletions

diff --git a/Main.hs b/Main.hs
index c3e18c9..b8e2ce4 100644
--- a/Main.hs
+++ b/Main.hs
@@ -8,125 +8,17 @@ import Data.Bool
 import Data.Foldable
 import Data.Function
 import Data.List
-import Data.Maybe
 import Data.Traversable
-import Opts
-import System.Environment
 import System.Exit
 import System.FilePath
 import System.IO
 import System.IO.Temp
-import System.Process
 
+import Opts
+import Progs
 import qualified Toks
 import Toks (Tok)
 
-import Debug.Trace
-
-{-
- - interface to other programs
- -}
-diffProg = fromMaybe "diff" <$> lookupEnv "WERGE_DIFF"
-
-gitProg = fromMaybe "git" <$> lookupEnv "WERGE_GIT"
-
-bracketFile path mode = bracket (openFile path mode) hClose
-
-rundiff f1 f2 out = do
-  diff <- diffProg
-  st <-
-    bracketFile out WriteMode $ \oh ->
-      withCreateProcess
-        (proc
-           diff
-           [ "--text"
-           , "--new-line-format=+%L"
-           , "--old-line-format=-%L"
-           , "--unchanged-line-format= %L"
-           , f1
-           , f2
-           ])
-          {std_in = NoStream, std_out = UseHandle oh} $ \_ _ _ -> waitForProcess
-  when (st == ExitFailure 2) $ error "diff failed"
-  unless (st `elem` [ExitSuccess, ExitFailure 1])
-    $ error "diff failed for unknown reason (is GNU diffutils installed?)"
-
-gitRepoRelRoot = do
-  git <- gitProg
-  (path, st) <-
-    withCreateProcess
-      (proc git ["rev-parse", "--show-cdup"])
-        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
-      (,) <$> hGetContents' oh <*> waitForProcess p
-  unless (st == ExitSuccess) $ error "git failed"
-  let [p] = lines path
-  pure p
-
-gitUnmerged = do
-  git <- gitProg
-  (paths, st) <-
-    withCreateProcess
-      (proc git ["status", "--porcelain=v1"])
-        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
-      (,)
-        <$> (map (drop 3) . filter ("UU " `isPrefixOf`) . lines
-               <$> hGetContents' oh)
-        <*> waitForProcess p
-  unless (st == ExitSuccess) $ error "git failed"
-  pure paths
-
-gitCheckoutMOY cfg u my old your = do
-  git <- gitProg
-  (paths, st) <-
-    withCreateProcess
-      (proc git ["ls-files", "--unmerged", "--", u])
-        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
-      (,)
-        <$> (sortOn snd
-               . map ((\[a, b] -> (a, b)) . take 2 . drop 1 . words)
-               . lines
-               <$> hGetContents' oh)
-        <*> waitForProcess p
-  unless (st == ExitSuccess) $ error "git failed"
-  let co (hash, _) path = do
-        st <-
-          withCreateProcess
-            (proc "git" ["cat-file", "blob", hash])
-              {std_in = NoStream, std_out = CreatePipe} $ \_ (Just ho) _ p -> do
-            hSplitToFile cfg ho path
-            waitForProcess p
-        unless (st == ExitSuccess) . error
-          $ "failed checking out " ++ u ++ " from blob " ++ hash
-  case paths of
-    [(_, "1"), (_, "2"), (_, "3")] ->
-      zipWithM co paths [old, my, your] >> pure ()
-    _ -> error $ "bad data from ls-files for unmerged " ++ u
-
-gitAdd path = do
-  git <- gitProg
-  st <- rawSystem git ["add", "--", path]
-  unless (st == ExitSuccess) $ error "git-add failed"
-
-{-
- - configurable splitting
- -
- - TODO this should probably enforce joinSpaces?
- - or have joinSpaces as configurable? (probably best, default true)
- -}
-hSplitToFile cfg h path =
-  case cfgTokenizer cfg of
-    TokenizeCharCategory -> internal Toks.splitCategory
-    TokenizeCharCategorySimple -> internal Toks.splitSimple
-    TokenizeFilter cmd -> do
-      st <-
-        bracketFile path WriteMode $ \ho ->
-          withCreateProcess
-            (shell cmd) {std_in = UseHandle h, std_out = UseHandle ho} $ \_ _ _ ->
-            waitForProcess
-      unless (st == ExitSuccess) $ error "tokenize filter failed"
-  where
-    internal s = hGetContents h >>= writeFile path . Toks.toFile . s
-
 {-
  - merge algorithms
  -}
@@ -142,7 +34,7 @@ pdiff path = map go . lines <$> readFile path
     go ('-':s) = (Del, s)
     go (' ':s) = (Keep, s)
     go ('+':s) = (Add, s)
-    go [] = error "unexpected output from diff"
+    go _ = error "unexpected output from diff"
 
 data Merged
   = Ok [String]
@@ -150,9 +42,11 @@ data Merged
   | Conflict [String] [String] [String]
   deriving (Show)
 
+isKeepTok :: (Op, String) -> Bool
 isKeepTok (Keep, _) = True
 isKeepTok _ = False
 
+isDelTok :: (Op, String) -> Bool
 isDelTok (Del, _) = True
 isDelTok _ = False
 
@@ -170,6 +64,7 @@ chunks xs =
   let (reps, ys) = break isKeepTok xs
    in uncurry (Replace `on` map snd) (partition isDelTok reps) : chunks ys
 
+align1 :: Eq a => [a] -> [a] -> ([a], [a], [a])
 align1 as [] = ([], as, [])
 align1 [] bs = ([], [], bs)
 align1 (a:as) (b:bs)
@@ -178,7 +73,7 @@ align1 (a:as) (b:bs)
 align1 _ _ = error "chunks do not align"
 
 align :: [Merged] -> [Merged] -> [Merged]
-align m y = connect $ slice m y
+align m0 y0 = connect $ slice m0 y0
   where
     erase x = Replace x []
     nemap _ [] = []
@@ -204,13 +99,14 @@ align m y = connect $ slice m y
     slice _ _ = error "unacceptable chunks"
     coFlag (Ok _) = False
     coFlag (Replace _ _) = True
+    coFlag _ = error "flagging unacceptable chunks"
     coSig (a, b) = (coFlag a, coFlag b)
     coConn' (a, b) (a', b') = (a && a') || (b && b')
     coConn = coConn' `on` coSig
     coGroup [] = []
     coGroup (x:xs) =
       case coGroup xs of
-        xs'@(ys@(y:_):yss)
+        (ys@(y:_):yss)
           | coConn x y -> (x : ys) : yss
         xs' -> [x] : xs'
     connect = map confl . coGroup
@@ -218,12 +114,14 @@ align m y = connect $ slice m y
     toCon (Ok o, Replace _ y) = Conflict o o y
     toCon (Replace o m, Ok _) = Conflict m o o
     toCon (Replace o m, Replace _ y) = Conflict m o y
-    confl = foldr cappend (Ok []) . map toCon
-    cappend (Ok x) (Ok o) = Ok (x ++ o)
-    cappend (Ok x) (Conflict m o y) = error "align consistency check fail" -- Conflict (x++m) (x++o) (x++y)
-    cappend (Conflict m o y) (Ok x) = Conflict (m ++ x) (o ++ x) (y ++ x)
-    cappend (Conflict m o y) (Conflict m' o' y') =
+    toCon _ = error "converting unacceptable chunks"
+    confl = foldr coAppend (Ok []) . map toCon
+    coAppend (Ok x) (Ok o) = Ok (x ++ o)
+    coAppend (Ok _) (Conflict _ _ _) = error "align consistency check fail" -- Conflict (x++m) (x++o) (x++y)
+    coAppend (Conflict m o y) (Ok x) = Conflict (m ++ x) (o ++ x) (y ++ x)
+    coAppend (Conflict m o y) (Conflict m' o' y') =
       Conflict (m ++ m') (o ++ o') (y ++ y')
+    coAppend _ _ = error "appending unacceptable chunks"
 
 regroup :: [Merged] -> [Merged]
 regroup [] = []
@@ -234,10 +132,11 @@ regroup (x@(Ok a):xs) =
     xs' -> x : xs'
 regroup (x:xs) = x : regroup xs
 
-zeal Config {..} (Conflict m o y) =
-  before' ++ (Conflict (reverse m'') o (reverse y'') : after')
+zeal :: Config -> Merged -> [Merged]
+zeal Config {..} (Conflict m0 o0 y0) =
+  before' ++ (Conflict (reverse m'') o0 (reverse y'') : after')
   where
-    ((m', y'), before) = pops m y
+    ((m', y'), before) = pops m0 y0
     ((m'', y''), rafter) = pops (reverse m') (reverse y')
     before' =
       case before of
@@ -258,6 +157,7 @@ zeal Config {..} (Conflict m o y) =
     pops ms ys = ((ms, ys), [])
 zeal _ x = [x]
 
+resolveSpace :: Config -> Merged -> Merged
 resolveSpace Config {..} c@(Conflict m o y)
   | not (all Toks.space $ concat [m, o, y]) = c
   | m == o && o == y = Ok o
@@ -290,6 +190,7 @@ expand n = go
         xs' -> x : xs'
     go (x:xs) = x : go xs
 
+resolve :: Config -> Merged -> Merged
 resolve cfg@Config {..} c@(Conflict m o y)
   | cfgSpaceResolution /= SpaceNormal
   , all Toks.space (concat [m, o, y]) = resolveSpace cfg c
@@ -305,6 +206,7 @@ resolve cfg@Config {..} c@(Conflict m o y)
       ResolveKeep -> c
 resolve _ x = x
 
+merge :: Config -> [(Op, String)] -> [(Op, String)] -> [Merged]
 merge cfg@Config {..} ms ys =
   regroup
     . map (resolve cfg)
@@ -325,7 +227,7 @@ format Config {..} h = go False
     go c (Ok x:xs) = do
       hPutStr h (Toks.glue x)
       go c xs
-    go c (Conflict m o y:xs) = do
+    go _ (Conflict m o y:xs) = do
       hPutStr h
         $ mconcat
             [ cfgLabelStart
@@ -337,7 +239,9 @@ format Config {..} h = go False
             , cfgLabelEnd
             ]
       go True xs
+    go _ _ = error "bad format (replace)"
 
+runCmd :: Command -> Config -> IO ()
 runCmd CmdDiff3 {..} cfg =
   withSystemTempDirectory "werge-diff3" $ \workdir -> do
     let [fMy, fOld, fYour, fdMy, fdYour] =
@@ -378,9 +282,7 @@ runCmd CmdGitMerge {..} cfg = do
 main :: IO ()
 main = catch go bad
   where
-    go = do
-      (cfg, cmd) <- parseOpts
-      runCmd cmd cfg
+    go = parseOpts >>= uncurry (flip runCmd)
     bad e = do
       hPutStrLn stderr $ "fatal: " ++ displayException (e :: IOException)
       exitWith (ExitFailure 2)
diff --git a/Opts.hs b/Opts.hs
index 7358951..dc6987f 100644
--- a/Opts.hs
+++ b/Opts.hs
@@ -16,6 +16,7 @@ data Tokenizer
   | TokenizeCharCategorySimple
   deriving (Show)
 
+tokenizer :: Parser Tokenizer
 tokenizer =
   asum
     [ TokenizeFilter
@@ -44,6 +45,7 @@ data ConflictMask = ConflictMask
   , cmResolveSeparate :: Bool
   } deriving (Show)
 
+conflictMask :: String -> String -> Parser ConflictMask
 conflictMask label objs = do
   cmResolveOverlaps' <-
     fmap not . switch
@@ -70,6 +72,7 @@ data Resolution
   | ResolveYour
   deriving (Show, Eq)
 
+resolutionMode :: String -> Either String Resolution
 resolutionMode x
   | x `isPrefixOf` "keep" = Right ResolveKeep
   | x `isPrefixOf` "my" = Right ResolveMy
@@ -86,6 +89,7 @@ data SpaceResolution
   | SpaceSpecial Resolution
   deriving (Show, Eq)
 
+spaceMode :: String -> Either String SpaceResolution
 spaceMode x
   | x `isPrefixOf` "normal" = Right SpaceNormal
   | Right y <- resolutionMode x = Right (SpaceSpecial y)
@@ -110,6 +114,7 @@ data Config = Config
   , cfgLabelEnd :: String
   } deriving (Show)
 
+config :: Parser Config
 config = do
   cfgTokenizer <- tokenizer
   cfgZealous <-
@@ -212,6 +217,7 @@ data Command
       }
   deriving (Show)
 
+cmdDiff3 :: Parser Command
 cmdDiff3 = do
   d3my <- strArgument $ metavar "MYFILE" <> help "Version with local edits"
   d3old <- strArgument $ metavar "OLDFILE" <> help "Original file version"
@@ -219,13 +225,15 @@ cmdDiff3 = do
     strArgument $ metavar "YOURFILE" <> help "Version with other people's edits"
   pure CmdDiff3 {..}
 
+cmdGitMerge :: Parser Command
 cmdGitMerge = do
   gmFiles <-
     asum
       [ fmap Just . some
           $ strArgument
           $ metavar "UNMERGED"
-              <> help "Unmerged file tracked by git (can be specified repeatedly)"
+              <> help
+                   "Unmerged file tracked by git (can be specified repeatedly)"
       , flag'
           Nothing
           (long "unmerged"
@@ -246,6 +254,7 @@ cmdGitMerge = do
 
 -- TODO have some option to output the (partially merged) my/old/your files so
 -- that folks can continue with external program or so (such as meld)
+cmd :: Parser Command
 cmd =
   hsubparser
     $ mconcat
diff --git a/Progs.hs b/Progs.hs
new file mode 100644
index 0000000..bb20726
--- /dev/null
+++ b/Progs.hs
@@ -0,0 +1,131 @@
+module Progs where
+
+import Control.Exception
+import Control.Monad
+import Data.List
+import Data.Maybe
+import System.Environment
+import System.Exit
+import System.IO
+import System.Process
+
+import Opts
+import qualified Toks
+
+bracketFile :: FilePath -> IOMode -> (Handle -> IO c) -> IO c
+bracketFile path mode = bracket (openFile path mode) hClose
+
+{-
+ - interface to gnu diff
+ -}
+diffProg :: IO String
+diffProg = fromMaybe "diff" <$> lookupEnv "WERGE_DIFF"
+
+rundiff :: FilePath -> FilePath -> FilePath -> IO ()
+rundiff f1 f2 out = do
+  diff <- diffProg
+  st <-
+    bracketFile out WriteMode $ \oh ->
+      withCreateProcess
+        (proc
+           diff
+           [ "--text"
+           , "--new-line-format=+%L"
+           , "--old-line-format=-%L"
+           , "--unchanged-line-format= %L"
+           , f1
+           , f2
+           ])
+          {std_in = NoStream, std_out = UseHandle oh} $ \_ _ _ -> waitForProcess
+  when (st == ExitFailure 2) $ error "diff failed"
+  unless (st `elem` [ExitSuccess, ExitFailure 1])
+    $ error "diff failed for unknown reason (is GNU diffutils installed?)"
+
+{-
+ - interface to git
+ -}
+gitProg :: IO String
+gitProg = fromMaybe "git" <$> lookupEnv "WERGE_GIT"
+
+gitRepoRelRoot :: IO FilePath
+gitRepoRelRoot = do
+  git <- gitProg
+  (path, st) <-
+    withCreateProcess
+      (proc git ["rev-parse", "--show-cdup"])
+        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
+      (,) <$> hGetContents' oh <*> waitForProcess p
+  unless (st == ExitSuccess) $ error "git failed"
+  case lines path of
+    [p] -> pure p
+    _ -> fail "bad git-rev-parse output"
+
+gitUnmerged :: IO [FilePath]
+gitUnmerged = do
+  git <- gitProg
+  (paths, st) <-
+    withCreateProcess
+      (proc git ["status", "--porcelain=v1"])
+        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
+      (,)
+        <$> (map (drop 3) . filter ("UU " `isPrefixOf`) . lines
+               <$> hGetContents' oh)
+        <*> waitForProcess p
+  unless (st == ExitSuccess) $ error "git failed"
+  pure paths
+
+gitCheckoutMOY ::
+     Config -> FilePath -> FilePath -> FilePath -> FilePath -> IO ()
+gitCheckoutMOY cfg u my old your = do
+  git <- gitProg
+  (paths, st) <-
+    withCreateProcess
+      (proc git ["ls-files", "--unmerged", "--", u])
+        {std_in = NoStream, std_out = CreatePipe} $ \_ (Just oh) _ p ->
+      (,)
+        <$> (sortOn snd
+               . map ((\[a, b] -> (a, b)) . take 2 . drop 1 . words)
+               . lines
+               <$> hGetContents' oh)
+        <*> waitForProcess p
+  unless (st == ExitSuccess) $ error "git failed"
+  let co (hash, _) path = do
+        st' <-
+          withCreateProcess
+            (proc "git" ["cat-file", "blob", hash])
+              {std_in = NoStream, std_out = CreatePipe} $ \_ (Just ho) _ p -> do
+            hSplitToFile cfg ho path
+            waitForProcess p
+        unless (st' == ExitSuccess) . error
+          $ "failed checking out " ++ u ++ " from blob " ++ hash
+  case paths of
+    [(_, "1"), (_, "2"), (_, "3")] ->
+      zipWithM co paths [old, my, your] >> pure ()
+    _ -> error $ "bad data from ls-files for unmerged " ++ u
+
+gitAdd :: FilePath -> IO ()
+gitAdd path = do
+  git <- gitProg
+  st <- rawSystem git ["add", "--", path]
+  unless (st == ExitSuccess) $ error "git-add failed"
+
+{-
+ - interface to external tokenizers
+ -
+ - TODO this might probably enforce joinSpaces?
+ - or have joinSpaces as configurable? (probably best, default true)
+ -}
+hSplitToFile :: Config -> Handle -> FilePath -> IO ()
+hSplitToFile cfg h path =
+  case cfgTokenizer cfg of
+    TokenizeCharCategory -> internal Toks.splitCategory
+    TokenizeCharCategorySimple -> internal Toks.splitSimple
+    TokenizeFilter fltr -> do
+      st <-
+        bracketFile path WriteMode $ \ho ->
+          withCreateProcess
+            (shell fltr) {std_in = UseHandle h, std_out = UseHandle ho} $ \_ _ _ ->
+            waitForProcess
+      unless (st == ExitSuccess) $ error "tokenize filter failed"
+  where
+    internal s = hGetContents h >>= writeFile path . Toks.toFile . s
diff --git a/Toks.hs b/Toks.hs
index bff68e6..54240e1 100644
--- a/Toks.hs
+++ b/Toks.hs
@@ -15,11 +15,11 @@ unescape :: String -> String
 unescape [] = []
 unescape ('\\':'\\':xs) = '\\' : unescape xs
 unescape ('\\':'n':xs) = '\n' : unescape xs
-unescape ('\\':_) = error "bad escape?"
+unescape ('\\':_) = error "bad escape on input"
 unescape (x:xs) = x : unescape xs
 
 markSpace :: String -> Tok
-markSpace [] = error "wat"
+markSpace [] = error "empty token"
 markSpace s@(c:_)
   | isSpace c = '.' : s
   | otherwise = '|' : s
@@ -27,7 +27,7 @@ markSpace s@(c:_)
 unmarkSpace :: Tok -> String
 unmarkSpace ('.':s) = s
 unmarkSpace ('|':s) = s
-unmarkSpace x = error "unwat"
+unmarkSpace _ = error "bad space marking on input"
 
 space :: Tok -> Bool
 space ('.':_) = True
diff --git a/werge.cabal b/werge.cabal
index 6202ccc..f8b8c84 100644
--- a/werge.cabal
+++ b/werge.cabal
@@ -22,8 +22,9 @@ executable werge
   main-is:          Main.hs
   other-modules:
     Opts
-    Toks
     Paths_werge
+    Progs
+    Toks
 
   autogen-modules:  Paths_werge
   build-depends: