Revert "Roff reader: custom Stream type."

This reverts commit 211f7ffc78ea1df49a685ac1160fa3942b3a3569.

We were getting stack overflows.  Not sure why.

1 files changed, 27 insertions, 51 deletions

diff --git a/src/Text/Pandoc/Readers/Roff.hs b/src/Text/Pandoc/Readers/Roff.hs
index d46ddd103..4919c5bc0 100644
--- a/src/Text/Pandoc/Readers/Roff.hs
+++ b/src/Text/Pandoc/Readers/Roff.hs
@@ -1,7 +1,4 @@
 {-# LANGUAGE FlexibleContexts #-}
-{-# LANGUAGE FlexibleInstances #-}
-{-# LANGUAGE MultiParamTypeClasses #-}
-{-# LANGUAGE StandaloneDeriving #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-
   Copyright (C) 2018 Yan Pashkovsky <yanp.bugz@gmail.com>
@@ -51,9 +48,8 @@ where
 
 import Prelude
 import Safe (lastDef)
-import Control.Monad (void, mzero, mplus, guard)
+import Control.Monad (void, mzero, mplus)
 import Control.Monad.Except (throwError)
-import Control.Monad.State.Strict (StateT(..), evalStateT, get, modify, put)
 import Text.Pandoc.Class
        (getResourcePath, readFileFromDirs, PandocMonad(..), report)
 import Data.Char (isLower, toLower, toUpper, chr,
@@ -121,7 +117,8 @@ data RoffMode = NormalMode
               | CopyMode
               deriving Show
 
-data RoffState = RoffState { prevFont       :: FontSpec
+data RoffState = RoffState { customMacros   :: M.Map String RoffTokens
+                           , prevFont       :: FontSpec
                            , currentFont    :: FontSpec
                            , tableTabChar   :: Char
                            , roffMode       :: RoffMode
@@ -129,17 +126,7 @@ data RoffState = RoffState { prevFont       :: FontSpec
                            } deriving Show
 
 instance Default RoffState where
-  def = RoffState { prevFont = defaultFontSpec
-                  , currentFont = defaultFontSpec
-                  , tableTabChar = '\t'
-                  , roffMode = NormalMode
-                  , lastExpression = Nothing
-                  }
-
-type MacroState = M.Map String RoffTokens
-
-initialMacroState :: MacroState
-initialMacroState = M.fromList
+  def = RoffState { customMacros = M.fromList
                        $ map (\(n, s) ->
                                 (n, singleTok
                                   (TextLine [RoffStr s])))
@@ -147,19 +134,14 @@ initialMacroState = M.fromList
                        , ("lq", "\x201C")
                        , ("rq", "\x201D")
                        , ("R",  "\x00AE") ]
+                  , prevFont = defaultFontSpec
+                  , currentFont = defaultFontSpec
+                  , tableTabChar = '\t'
+                  , roffMode = NormalMode
+                  , lastExpression = Nothing
+                  }
 
-newtype RoffStream = RoffStream{ unRoffStream :: [Char] }
-  deriving (Show)
-
-deriving instance Semigroup RoffStream
-deriving instance Monoid RoffStream
-
-instance Monad m => Stream RoffStream (StateT MacroState m) Char
-  where
-    uncons (RoffStream [])     = return Nothing
-    uncons (RoffStream (c:cs)) = return (Just (c, RoffStream cs))
-
-type RoffLexer m = ParserT RoffStream RoffState (StateT MacroState m)
+type RoffLexer m = ParserT [Char] RoffState m
 
 --
 -- Lexer: String -> RoffToken
@@ -230,14 +212,14 @@ readUnicodeChar _ = Nothing
 escapeNormal :: PandocMonad m => RoffLexer m [LinePart]
 escapeNormal = do
   c <- anyChar
-  (case c of
+  case c of
     ' ' -> return [RoffStr " "]
     '"' -> mempty <$ skipMany (satisfy (/='\n')) -- line comment
     '#' -> mempty <$ manyTill anyChar newline
     '%' -> return mempty  -- optional hyphenation
     '&' -> return mempty  -- nonprintable zero-width
     ')' -> return mempty  -- nonprintable zero-width
-    '*' -> escString <|> escIgnore '*' []
+    '*' -> escString
     ',' -> return mempty  -- to fix spacing after roman
     '-' -> return [RoffStr "-"]
     '.' -> return [RoffStr "`"]
@@ -301,7 +283,7 @@ escapeNormal = do
         CopyMode   -> char '\\'
         NormalMode -> return '\\'
       return [RoffStr "\\"]
-    _   -> return [RoffStr [c]]) <|> escIgnore c []
+    _   -> return [RoffStr [c]]
     -- man 7 groff: "If  a  backslash  is followed by a character that
     -- does not constitute a defined escape sequence, the backslash
     -- is  silently  ignored  and  the character maps to itself."
@@ -312,8 +294,7 @@ escIgnore :: PandocMonad m
           -> RoffLexer m [LinePart]
 escIgnore c argparsers = do
   pos <- getPosition
-  pos' <- (optional (choice argparsers) >> getPosition)
-  arg <- manyTill anyChar (getPosition >>= guard . (== pos'))
+  arg <- snd <$> withRaw (choice argparsers) <|> return ""
   report $ SkippedContent ('\\':c:arg) pos
   return mempty
 
@@ -515,20 +496,17 @@ lexConditional mname = do
                then fmap not . lastExpression <$> getState
                else expression
   skipMany spacetab
-  macros <- get -- save macro state, so we can reset it
-  st <- getState
+  st <- getState -- save state, so we can reset it
   ifPart <- lexGroup
         <|> (char '\\' >> newline >> manToken)
         <|> manToken
   case mbtest of
     Nothing    -> do
-      put macros  -- reset state, so we don't record macros in skipped section
-      putState st
+      putState st  -- reset state, so we don't record macros in skipped section
       report $ SkippedContent ('.':mname) pos
       return mempty
     Just True  -> return ifPart
     Just False -> do
-      put macros
       putState st
       return mempty
 
@@ -565,14 +543,14 @@ lexIncludeFile args = do
       result <- readFileFromDirs dirs fp
       case result of
         Nothing  -> report $ CouldNotLoadIncludeFile fp pos
-        Just s   -> getInput >>= setInput . (RoffStream s <>) -- TODO sourcepos!
+        Just s   -> getInput >>= setInput . (s ++)
       return mempty
     []    -> return mempty
 
 resolveMacro :: PandocMonad m
              => String -> [Arg] -> SourcePos -> RoffLexer m RoffTokens
 resolveMacro macroName args pos = do
-  macros <- get
+  macros <- customMacros <$> getState
   case M.lookup macroName macros of
     Nothing -> return $ singleTok $ ControlLine macroName args pos
     Just ts -> do
@@ -593,7 +571,8 @@ lexStringDef args = do -- string definition
      (x:ys) -> do
        let ts = singleTok $ TextLine (intercalate [RoffStr " " ] ys)
        let stringName = linePartsToString x
-       modify (M.insert stringName ts)
+       modifyState $ \st ->
+         st{ customMacros = M.insert stringName ts (customMacros st) }
    return mempty
 
 lexMacroDef :: PandocMonad m => [Arg] -> RoffLexer m RoffTokens
@@ -612,8 +591,9 @@ lexMacroDef args = do -- macro definition
          _ <- lexArgs
          return ()
    ts <- mconcat <$> manyTill manToken stop
-   modify (M.insert macroName ts)
-   modifyState $ \st -> st{ roffMode = NormalMode }
+   modifyState $ \st ->
+     st{ customMacros = M.insert macroName ts (customMacros st)
+       , roffMode = NormalMode }
    return mempty
 
 lexArgs :: PandocMonad m => RoffLexer m [Arg]
@@ -655,7 +635,7 @@ lexArgs = do
 
 checkDefined :: PandocMonad m => String -> RoffLexer m [LinePart]
 checkDefined name = do
-  macros <- get
+  macros <- customMacros <$> getState
   case M.lookup name macros of
     Just _  -> return [RoffStr "1"]
     Nothing -> return [RoffStr "0"]
@@ -749,12 +729,8 @@ linePartsToString = mconcat . map go
 -- | Tokenize a string as a sequence of roff tokens.
 lexRoff :: PandocMonad m => SourcePos -> T.Text -> m RoffTokens
 lexRoff pos txt = do
-  eithertokens <- evalStateT
-                   (readWithM
-                      (do setPosition pos
-                          mconcat <$> many manToken) def
-                       (RoffStream (T.unpack txt)))
-                   initialMacroState
+  eithertokens <- readWithM (do setPosition pos
+                                mconcat <$> many manToken) def (T.unpack txt)
   case eithertokens of
     Left e       -> throwError e
     Right tokenz -> return tokenz