haskell-indentation mode sometimes can't parse multiline string literals

[kini]

As title. The following code produces parse errors if you hit tab after the last line:

main :: IO ()
main = do
  putStrLn "\
  \foo\
  \bar"

So does this code:

main :: IO ()
main = do
  putStrLn "\
  \foo\
 \bar"

But this code doesn't produce a parse error (though the tab stop produced is a little odd)

main :: IO ()
main = do
  putStrLn "\
  \foo\
   \bar"

Same with all of these code samples:

main :: IO ()
main = do
  putStrLn "\
   \foo\
  \bar"

main :: IO ()
main = do
  putStrLn "\
   \foo\
   \bar"

main :: IO ()
main = do
  putStrLn "\
 \foo\
 \bar"

All the examples above are compiled by GHC without complaint.

[gracjan]

This one got slightly better due to #552, but not exactly right yet.

[gracjan]

This seems to be fixed properly by now. Leave a message here if you disagree.