Fix wordWithQuotes for a case where the string ends with an esc char

core/src/Streamly/Internal/Data/Parser.hs

@@ -1756,6 +1756,19 @@ wordWithQuotes keepQuotes tr escChar toRight isSep
                 FL.Partial s1 -> Continue 0 (WordUnquotedWord s1)
                 FL.Done b -> Done 0 b
 
+    {-# INLINE checkQuoteEnd #-}
+    checkQuoteEnd s a n ql qr =
+        if a == qr
+        then
+           if n == 1
+           then if keepQuotes
+                then processUnquoted s a
+                else return $ Continue 0 $ WordUnquotedWord s
+           else processQuoted s a (n - 1) ql qr
+        else if a == ql
+             then processQuoted s a (n + 1) ql qr
+             else processQuoted s a n ql qr
+
     step (WordQuotedSkipPre s) a
         | isEsc a = return $ Continue 0 $ WordUnquotedEsc s
         | isSep a = return $ Partial 0 $ WordQuotedSkipPre s
@@ -1792,24 +1805,14 @@ wordWithQuotes keepQuotes tr escChar toRight isSep
             b <- fextract s
             return $ Partial 0 $ WordQuotedSkipPost b
         -}
-        | otherwise = do
-                if a == qr
-                then
-                   if n == 1
-                   then if keepQuotes
-                        then processUnquoted s a
-                        else return $ Continue 0 $ WordUnquotedWord s
-                   else processQuoted s a (n - 1) ql qr
-                else if a == ql
-                     then processQuoted s a (n + 1) ql qr
-                     else processQuoted s a n ql qr
+        | otherwise = checkQuoteEnd s a n ql qr
     step (WordUnquotedEsc s) a = processUnquoted s a
     step (WordQuotedEsc s n ql qr) a =
         case tr ql a of
             Nothing -> do
                 res <- fstep s escChar
                 case res of
-                    FL.Partial s1 -> processQuoted s1 a n ql qr
+                    FL.Partial s1 -> checkQuoteEnd s1 a n ql qr
                     FL.Done b -> return $ Done 0 b
             Just x -> processQuoted s x n ql qr
     step (WordQuotedSkipPost b) a =

test/Streamly/Test/Data/Parser.hs

@@ -6,11 +6,10 @@ module Main (main) where
 
 import Control.Applicative ((<|>))
 import Control.Exception (displayException)
+import Data.Char (isSpace)
 import Data.Foldable (for_)
 import Data.Word (Word8, Word32, Word64)
 import Streamly.Test.Common (listEquals, checkListEqual, chooseInt)
-import Test.Hspec (Spec, hspec, describe)
-import Test.Hspec.QuickCheck
 import Test.QuickCheck
        (arbitrary, forAll, elements, Property, property, listOf,
         vectorOf, Gen, (.&&.))
@@ -29,6 +28,9 @@ import qualified Streamly.Internal.Data.Producer as Producer
 import qualified Streamly.Internal.Data.Unfold as Unfold
 import qualified Test.Hspec as H
 
+import Test.Hspec
+import Test.Hspec.QuickCheck
+
 #if MIN_VERSION_QuickCheck(2,14,0)
 
 import Test.QuickCheck (chooseAny)
@@ -1271,6 +1273,33 @@ takeStartBy_ =
             where
                 predicate = odd
                 parser = P.takeStartBy_ predicate FL.toList
+
+quotedWordTest :: String -> [String] -> IO ()
+quotedWordTest inp expected = do
+    res <-
+        S.fold FL.toList
+            $ catRightsErr
+            $ S.parseMany quotedWord $ S.fromList inp
+    res `shouldBe` expected
+    where
+    catRightsErr = fmap (either (error . displayException) id)
+    quotedWord =
+        let toRQuote x =
+                case x of
+                    '"' -> Just x
+                    '\'' -> Just x
+                    _ -> Nothing
+            -- Inside ",
+            -- * \\ is translated to \
+            -- * \" is translated to "
+            trEsc '"' x =
+                case x of
+                    '\\' -> Just '\\'
+                    '"' -> Just '"'
+                    _ -> Nothing
+            trEsc _ _ = Nothing
+         in P.wordWithQuotes False trEsc '\\' toRQuote isSpace FL.toList
+
 -------------------------------------------------------------------------------
 -- Main
 -------------------------------------------------------------------------------
@@ -1377,3 +1406,12 @@ main =
         prop "takeStartBy_" takeStartBy_
 
     takeProperties
+
+    describe "quotedWordTest" $ do
+        it "Single quote test" $ do
+           quotedWordTest "'hello\\\\\"world'" ["hello\\\\\"world"]
+           quotedWordTest "'hello\\'" ["hello\\"]
+        it "Double quote test" $ do
+           quotedWordTest
+               "\"hello\\\"\\\\w\\'orld\""
+               ["hello\"\\w\\'orld"]