Strange MultiWayIf indentation problem in Haskell

Test.hs

{-# LANGUAGE MultiWayIf #-}

test1 :: Maybe String -> String
test1 x =
  case () of
    _ | True
      -> "Good morning"
test2 :: Maybe String -> String
test2 x =
  if | True -> "Good morning"
     | False -> "Nope"

test3 :: Maybe String -> String
test3 x =
  if | Just n <- x -> "Hi"
     | otherwise   -> "Nope"

-- The following fails to parse because the -> are aligned with the |
test4 :: Maybe String -> String
test4 x =
  if | Just n <- x
     -> "Hi" 
     | otherwise
     -> "Nope"

test5 :: Maybe String -> String
test5 x =
  if | Just n <- x
      , length n > 5 -- Works only if line is more indented than previous line
      -> "Hi"
     | otherwise
      -> "Nope"

It may be unintuitive, but I don't think this is a bug. The threshold for the required indentation is set the next token following "of" for the case expression, or following "if" for the MultiWayIf. In the former case this is the pattern, and in the latter case this is the vertical bar. If you aligned the "->" with the beginning of the pattern (the underscore) in the case expression you'd get the same error. The continuation line has to be more indented than the token that began the block.