brittany-0.14.0.2: source/library/Language/Haskell/Brittany/Internal/Transformations/Par.hs

{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE NoImplicitPrelude #-}

module Language.Haskell.Brittany.Internal.Transformations.Par where

import Language.Haskell.Brittany.Internal.Prelude
import Language.Haskell.Brittany.Internal.Types
import Language.Haskell.Brittany.Internal.Utils



transformSimplifyPar :: BriDoc -> BriDoc
transformSimplifyPar = transformUp $ \case
  -- BDPar BrIndentNone line1 line2 -> Just $ BDLines [line1, line2]
  -- BDPar line indented ->
  --   Just $ BDLines [line, indented]
  -- BDPar ind1 (BDPar ind2 line p1) p2 | ind1==ind2 ->
  --   Just $ BDPar ind1 line (BDLines [p1, p2])
  x@(BDPar _ (BDPar _ BDPar{} _) _) -> x
  BDPar ind1 (BDPar ind2 line p1) (BDLines indenteds) ->
    BDPar ind1 line (BDLines (BDEnsureIndent ind2 p1 : indenteds))
  BDPar ind1 (BDPar ind2 line p1) p2 ->
    BDPar ind1 line (BDLines [BDEnsureIndent ind2 p1, p2])
  BDLines lines
    | any
      (\case
        BDLines{} -> True
        BDEmpty{} -> True
        _ -> False
      )
      lines
    -> case go lines of
      [] -> BDEmpty
      [x] -> x
      xs -> BDLines xs
   where
    go = (=<<) $ \case
      BDLines l -> go l
      BDEmpty -> []
      x -> [x]
  BDLines [] -> BDEmpty
  BDLines [x] -> x
  -- BDCols sig cols | BDPar ind line indented <- List.last cols ->
  --   Just $ BDPar ind (BDCols sig (List.init cols ++ [line])) indented
  -- BDPar BrIndentNone line indented ->
  --   Just $ BDLines [line, indented]
  BDEnsureIndent BrIndentNone x -> x
  x -> x