Muse reader: allow empty headers

Previously empty headers caused parser to terminate without parsing the rest of the document.

src/Text/Pandoc/Readers/Muse.hs

@@ -172,12 +172,6 @@ getIndent :: PandocMonad m
           => MuseParser m Int
 getIndent = subtract 1 . sourceColumn <$ many spaceChar <*> getPosition
 
-someUntil :: (Stream s m t)
-          => ParserT s u m a
-          -> ParserT s u m b
-          -> ParserT s u m ([a], b)
-someUntil p end = first <$> ((:) <$> p) <*> manyUntil p end
-
 -- ** HTML parsers
 
 openTag :: PandocMonad m => String -> MuseParser m [(String, String)]
@@ -462,7 +456,7 @@ paraContentsUntil :: PandocMonad m
                   => MuseParser m a -- ^ Terminator parser
                   -> MuseParser m (F Inlines, a)
 paraContentsUntil end = first (trimInlinesF . mconcat)
-  <$> someUntil inline (try (manyTill spaceChar eol *> local (\s -> s { museInPara = True}) end))
+  <$> manyUntil inline (try (manyTill spaceChar eol *> local (\s -> s { museInPara = True}) end))
 
 -- | Parse a paragraph.
 paraUntil :: PandocMonad m

test/Tests/Readers/Muse.hs

@@ -650,6 +650,13 @@ tests =
           T.unlines [ "* Foo"
                     , "bar"
                     ] =?> header 1 "Foo\nbar"
+        , "Empty header" =:
+          T.unlines [ "Foo"
+                    , ""
+                    , "* "
+                    , ""
+                    , "bar"
+                    ] =?> para (text "Foo") <> header 1 "" <> para (text "bar")
         , test (purely $ readMuse def { readerExtensions = extensionsFromList [Ext_amuse, Ext_auto_identifiers]})
                "Auto identifiers"
           (T.unlines [ "* foo"