Muse reader: remove indentation from examples indicated by {{{ and }}}

src/Text/Pandoc/Readers/Muse.hs

@@ -147,6 +147,9 @@ lchop s = s
 rchop :: String -> String
 rchop = reverse . lchop . reverse
 
+unindent :: String -> String
+unindent = rchop . intercalate "\n" . dropSpacePrefix . splitOn "\n" . lchop
+
 dropSpacePrefix :: [String] -> [String]
 dropSpacePrefix lns =
   map (drop maxIndent) lns
@@ -380,15 +383,15 @@ amuseHeadingUntil end = try $ do
 example :: PandocMonad m => MuseParser m (F Blocks)
 example = try $ pure . B.codeBlock
   <$  string "{{{"
-  <*  optional blankline
-  <*> manyTill anyChar (try (optional blankline *> string "}}}"))
+  <*  many spaceChar
+  <*> (unindent <$> manyTill anyChar (string "}}}"))
 
 -- | Parse an @\<example>@ tag.
 exampleTag :: PandocMonad m => MuseParser m (F Blocks)
 exampleTag = try $ fmap pure $ B.codeBlockWith
   <$  many spaceChar
   <*> (htmlAttrToPandoc <$> openTag "example")
-  <*> (rchop . intercalate "\n" . dropSpacePrefix . splitOn "\n" . lchop <$> manyTill anyChar (closeTag "example"))
+  <*> (unindent <$> manyTill anyChar (closeTag "example"))
   <*  manyTill spaceChar eol
 
 -- | Parse a @\<literal>@ tag as a raw block.
@@ -398,7 +401,7 @@ literalTag = try $ fmap pure $ B.rawBlock
   <$  many spaceChar
   <*> (fromMaybe "html" . lookup "style" <$> openTag "literal") -- FIXME: Emacs Muse inserts <literal> without style into all output formats, but we assume HTML
   <*  manyTill spaceChar eol
-  <*> (rchop . intercalate "\n" . dropSpacePrefix . splitOn "\n" . lchop <$> manyTill anyChar (closeTag "literal"))
+  <*> (unindent <$> manyTill anyChar (closeTag "literal"))
   <*  manyTill spaceChar eol
 
 -- | Parse @\<center>@ tag.

test/Tests/Readers/Muse.hs

@@ -459,6 +459,12 @@ tests =
                     , "}}}"
                     ] =?>
           codeBlock "Example line\n"
+        , "Indented braces" =:
+          T.unlines [ " - {{{"
+                    , "   Example line"
+                    , "   }}}"
+                    ] =?>
+          bulletList [ codeBlock "Example line" ]
         -- Amusewiki requires braces to be on separate line,
         -- this is an extension.
         , "One line" =: