GADT indentation does not work

[s9gf4ult]

Here is the code

data Collection (s :: [S]) (k :: key -> *) (f :: key -> *) where
  Rec     :: Record k f                   -> Collection '[] k f
  List    :: DList (Record k f)           -> Collection '[ 'L ] k f
  Grouped :: Map (DSum k f) (Collection s k f) -> Collection ('G ': s) k f

If I step at the end of declaration wanting to add new constructor, hi2 proposes me just one indentation position and it is totally wrong: