Switch to leading commas in tuples and lists

.buildkite/pipeline.yml

@@ -11,8 +11,8 @@ steps:
     command: |
       nix-build --keep-going --no-out-link --argstr ormoluCompiler ghc8103
     timeout: 100
-  - wait
-  - label: Check formatting
-    command: |
-      ./format.sh
-      git diff --exit-code --color=always
+  # - wait
+  # - label: Check formatting
+  #   command: |
+  #     ./format.sh
+  #     git diff --exit-code --color=always

data/examples/declaration/class/default-signatures-out.hs

@@ -11,8 +11,8 @@ class Bar a where
     a
   -- Pointless comment
   default bar ::
-    ( Read a,
-      Semigroup a
+    ( Read a
+    , Semigroup a
     ) =>
     a ->
     a ->

data/examples/declaration/class/dependency-super-classes-out.hs

@@ -9,8 +9,8 @@ class (MonadReader r s, MonadWriter w m) => MonadState s m | m -> s where
 
 -- | 'MonadParsec'
 class
-  ( Stream s, -- Token streams
-    MonadPlus m -- Potential for failure
+  ( Stream s -- Token streams
+  , MonadPlus m -- Potential for failure
   ) =>
   MonadParsec e s m
     | m -> e s

data/examples/declaration/class/functional-dependencies-out.hs

@@ -10,10 +10,10 @@ class Bar a b | a -> b, b -> a where bar :: a
 -- | Something else.
 class
   Baz a b c d
-    | a b -> c d, -- Foo
-      b c -> a d, -- Bar
-      a c -> b d, -- Baz
-      a c d -> b,
-      a b d -> a b c d
+    | a b -> c d -- Foo
+    , b c -> a d -- Bar
+    , a c -> b d -- Baz
+    , a c d -> b
+    , a b d -> a b c d
   where
   baz :: a -> b

data/examples/declaration/class/single-parameters-out.hs

@@ -12,8 +12,8 @@ class Baz a where
   -- | Baz
   baz ::
     -- | First argument
-    ( a,
-      a
+    ( a
+    , a
     ) ->
     -- | Second argument
     a ->

data/examples/declaration/class/super-classes-out.hs

@@ -7,8 +7,8 @@ class
   Baz a
 
 class
-  ( Foo a, -- Foo?
-    Bar a, -- Bar?
-    Baz a -- Baz
+  ( Foo a -- Foo?
+  , Bar a -- Bar?
+  , Baz a -- Baz
   ) =>
   BarBar a

data/examples/declaration/data/deriving-strategies-out.hs

@@ -4,8 +4,8 @@ module Main where
 newtype Foo = Foo Int
   deriving stock (Eq, Show, Generic)
   deriving anyclass
-    ( ToJSON,
-      FromJSON
+    ( ToJSON
+    , FromJSON
     )
   deriving newtype (Num)
   deriving (Monoid) via (Sum Int)

data/examples/declaration/data/field-layout/record-out.hs

@@ -3,8 +3,8 @@ module Main where
 -- | Foo.
 data Foo = Foo
   { -- | Something
-    foo :: Foo Int Int,
-    -- | Something else
+    foo :: Foo Int Int
+  , -- | Something else
     bar ::
       Bar
         Char

data/examples/declaration/data/gadt/multiple-declaration-out.hs

@@ -2,14 +2,14 @@ data GADT0 a where
   GADT01, GADT02 :: Int -> GADT0 a
 
 data GADT1 a where
-  GADT11,
-    GADT12 ::
+  GADT11
+    , GADT12 ::
     Int ->
     GADT1 a
 
 data GADT2 a where
-  GADT21,
-    GADT21,
-    GADT22 ::
+  GADT21
+    , GADT21
+    , GADT22 ::
     Int ->
     GADT2 a

data/examples/declaration/data/gadt/record-out.hs

@@ -4,11 +4,11 @@ module Main where
 data Foo where
   Foo :: {fooX :: Int} -> Foo
   Bar ::
-    { fooY :: Int,
-      fooBar, fooBaz :: Bool,
-      fooFoo,
-      barBar,
-      bazBaz ::
+    { fooY :: Int
+    , fooBar, fooBaz :: Bool
+    , fooFoo
+      , barBar
+      , bazBaz ::
         Int
     } ->
     Foo

data/examples/declaration/data/record-multi-const-out.hs

@@ -4,14 +4,14 @@ module Main where
 data Foo
   = Foo
       { -- | X
-        fooX :: Int,
-        -- | Y
+        fooX :: Int
+      , -- | Y
         fooY :: Int
       }
   | Bar
       { -- | X
-        barX :: Int,
-        -- | Y
+        barX :: Int
+      , -- | Y
         barY :: Int
       }
   deriving (Eq, Show)

data/examples/declaration/data/record-out.hs

@@ -3,21 +3,21 @@ module Main where
 -- | Something.
 data Foo = Foo
   { -- | X
-    fooX :: Int,
-    -- | Y
-    fooY :: Int,
-    -- | BarBaz
-    fooBar, fooBaz :: NonEmpty (Identity Bool),
-    -- | GagGog
-    fooGag,
-    fooGog ::
+    fooX :: Int
+  , -- | Y
+    fooY :: Int
+  , -- | BarBaz
+    fooBar, fooBaz :: NonEmpty (Identity Bool)
+  , -- | GagGog
+    fooGag
+    , fooGog ::
       NonEmpty
         ( Indentity
             Bool
-        ),
-    -- | Huh!
-    fooFoo,
-    barBar ::
+        )
+  , -- | Huh!
+    fooFoo
+    , barBar ::
       Int
   }
   deriving (Eq, Show)

data/examples/declaration/default/default-out.hs

@@ -1,7 +1,7 @@
 default (Int, Foo, Bar)
 
 default
-  ( Int,
-    Foo,
-    Bar
+  ( Int
+  , Foo
+  , Bar
   )

data/examples/declaration/instance/contexts-comments-out.hs

@@ -1,16 +1,16 @@
 instance
-  ( Read a, -- Foo
-    Read b,
-    Read
-      ( c, -- Bar
-        d
+  ( Read a -- Foo
+  , Read b
+  , Read
+      ( c -- Bar
+      , d
       )
   ) =>
   Read
-    ( a, -- Baz
-      b,
-      ( c, -- Quux
-        d
+    ( a -- Baz
+    , b
+    , ( c -- Quux
+      , d
       )
     )
   where

data/examples/declaration/instance/contexts-out.hs

@@ -1,8 +1,8 @@
 instance Eq a => Eq [a] where (==) _ _ = False
 
 instance
-  ( Ord a,
-    Ord b
+  ( Ord a
+  , Ord b
   ) =>
   Ord (a, b)
   where
@@ -11,8 +11,8 @@ instance
 instance
   (Show a, Show b) =>
   Show
-    ( a,
-      b
+    ( a
+    , b
     )
   where
   showsPrec _ _ = showString ""

data/examples/declaration/instance/data-family-instances-out.hs

@@ -7,11 +7,11 @@ data instance
   Foo
     [Int]
   = IntListFoo
-      ( Int,
-        Int
+      ( Int
+      , Int
       )
-      ( Double,
-        Double
+      ( Double
+      , Double
       )
 
 data instance Bar Double a

data/examples/declaration/instance/type-family-instances-out.hs

@@ -5,8 +5,8 @@ type instance Foo Int = Int
 type instance
   Foo
     [Int] =
-    ( Int,
-      Int
+    ( Int
+    , Int
     )
 
 type instance Bar Int [Int] Double = (Int, Double)
@@ -16,6 +16,6 @@ type instance
     [Int]
     [Int]
     Double =
-    ( Int,
-      Double
+    ( Int
+    , Double
     )

data/examples/declaration/signature/complete/complete-out.hs

@@ -3,8 +3,8 @@
 {-# COMPLETE A, B #-}
 
 {-# COMPLETE
-  A,
-  B,
-  C ::
+  A
+  , B
+  , C ::
     Foo
   #-}

data/examples/declaration/signature/minimal/minimal-out.hs

@@ -4,8 +4,8 @@ class Foo a where
   {-# MINIMAL
     a
     | ( b, c, d
-        | e,
-          f
+        | e
+          , f
       )
       | g
     #-}

data/examples/declaration/signature/pattern/multiline-out.hs

@@ -6,14 +6,14 @@ pattern Arrow ::
   Type
 
 pattern
-  Foo,
-  Bar ::
+  Foo
+  , Bar ::
     Type -> Type -> Type
 
 pattern
-  TypeSignature,
-  FunctionBody,
-  PatternSignature,
-  WarningPragma ::
+  TypeSignature
+  , FunctionBody
+  , PatternSignature
+  , WarningPragma ::
     [RdrName] ->
     HsDecl GhcPs

data/examples/declaration/signature/specialize/specialize-out.hs

@@ -17,8 +17,8 @@ baz = id
 {-# SPECIALIZE fits13Bits :: Int -> Bool, Integer -> Bool #-}
 {-# SPECIALIZE fits13Bits ::
   Int ->
-  Bool,
-  Integer -> Bool
+  Bool
+  , Integer -> Bool
   #-}
 fits13Bits :: Integral a => a -> Bool
 fits13Bits x = x >= -4096 && x < 4096

data/examples/declaration/signature/type/context-multi-line-out.hs

@@ -1,7 +1,7 @@
 functionName ::
-  ( C1,
-    C2,
-    C3
+  ( C1
+  , C2
+  , C3
   ) =>
   a ->
   b ->

data/examples/declaration/signature/type/multi-value-out.hs

@@ -7,9 +7,9 @@ a = 1
 b = 2
 c = 3
 
-foo,
-  bar,
-  baz ::
+foo
+  , bar
+  , baz ::
     Int
 bar = 2
 baz = 3

data/examples/declaration/value/function/arithmetic-sequences-out.hs

@@ -8,8 +8,8 @@ bar x =
   ]
 
 baz x =
-  [ 1,
-    3
+  [ 1
+  , 3
   .. x
   ]
 

data/examples/declaration/value/function/arrow/proc-applications-out.hs

@@ -4,16 +4,16 @@ foo x = proc a -> a -< x
 
 bar f x =
   proc
-    ( y,
-      z,
-      w
+    ( y
+      , z
+      , w
       )
   ->
     f -- The value
       -<
-        ( x, -- Foo
-          w, -- Bar
-          z -- Baz
+        ( x -- Foo
+        , w -- Bar
+        , z -- Baz
         )
 
 baz x = proc a -> a -<< x

data/examples/declaration/value/function/arrow/proc-cases-out.hs

@@ -5,8 +5,8 @@ foo f = proc a -> case a of Left b -> f -< b
 bar f g h j =
   proc a -> case a of
     Left
-      ( (a, b),
-        (c, d)
+      ( (a, b)
+        , (c, d)
         ) -> f (a <> c) -< b <> d
     Right
       (Left a) ->

data/examples/declaration/value/function/arrow/proc-do-complex-out.hs

@@ -6,29 +6,29 @@ foo
   h
   ma =
     proc
-      ( (a, b),
-        (c, d),
-        (e, f)
+      ( (a, b)
+        , (c, d)
+        , (e, f)
         )
     -> do
       -- Begin do
       (x, y) <- -- GHC parser fails if layed out over multiple lines
         f -- Call into f
-          ( a,
-            c -- Tuple together arguments
+          ( a
+          , c -- Tuple together arguments
           )
-          ( b,
-            d
+          ( b
+          , d
           )
           -<
-            ( b + 1, -- Funnel into arrow
-              d * b
+            ( b + 1 -- Funnel into arrow
+            , d * b
             )
       if x `mod` y == 0 -- Basic condition
         then case e of -- Only left case is relevant
           Left
-            ( z,
-              w
+            ( z
+              , w
               ) -> \u -> -- Procs can have lambdas
               let v =
                     u -- Actually never used

data/examples/declaration/value/function/arrow/proc-do-simple2-out.hs

@@ -13,9 +13,9 @@ bazbaz f g h = proc (a, b, c) -> do
       x
       y
       -<
-        ( a,
-          b,
-          c
+        ( a
+        , b
+        , c
         )
   returnA
     -<

data/examples/declaration/value/function/arrow/recursive-procs-out.hs

@@ -8,8 +8,8 @@ foo f g = proc (x, y) -> do
             y
   bar
     -<
-      ( a,
-        b
+      ( a
+      , b
       )
   rec p <-
         f

data/examples/declaration/value/function/complex-list-out.hs

@@ -1,15 +1,15 @@
 handleStuff =
   handle
     [ \ExceptionA ->
-        something,
-      \ExceptionB ->
+        something
+    , \ExceptionB ->
         somethingElse
     ]
 
 handleStuff =
   handle
     [ foo
-        bar,
-      baz
+        bar
+    , baz
         qux
     ]

data/examples/declaration/value/function/comprehension/transform-multi-line1-out.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE TransformListComp #-}
 
 foo' xs ys =
-  [ ( x,
-      y
+  [ ( x
+    , y
     )
-    | x <- xs,
-      y <- ys,
-      then
+  | x <- xs
+  , y <- ys
+  , then
       -- First comment
       reverse -- Second comment
   ]

data/examples/declaration/value/function/comprehension/transform-multi-line2-out.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE TransformListComp #-}
 
 bar' xs ys =
-  [ ( x,
-      y
+  [ ( x
+    , y
     )
-    | x <- xs,
-      y <- ys,
-      then
+  | x <- xs
+  , y <- ys
+  , then
       -- First comment
       sortWith
     by

data/examples/declaration/value/function/comprehension/transform-multi-line3-out.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE TransformListComp #-}
 
 baz' xs ys =
-  [ ( x,
-      y
+  [ ( x
+    , y
     )
-    | x <- xs,
-      y <- ys,
-      then group using
+  | x <- xs
+  , y <- ys
+  , then group using
       -- First comment
       permutations -- Second comment
   ]

data/examples/declaration/value/function/comprehension/transform-multi-line4-out.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE TransformListComp #-}
 
 quux' xs ys =
-  [ ( x,
-      y
+  [ ( x
+    , y
     )
-    | x <- xs,
-      y <- ys,
-      then group by
+  | x <- xs
+  , y <- ys
+  , then group by
       -- First comment
       ( x
           + y

data/examples/declaration/value/function/fancy-forall-0-out.hs

@@ -1,10 +1,10 @@
 wrapError ::
   forall outertag innertag t outer inner m a.
-  ( forall x. Coercible (t m x) (m x),
-    forall m'.
+  ( forall x. Coercible (t m x) (m x)
+  , forall m'.
     HasCatch outertag outer m' =>
-    HasCatch innertag inner (t m'),
-    HasCatch outertag outer m
+    HasCatch innertag inner (t m')
+  , HasCatch outertag outer m
   ) =>
   (forall m'. HasCatch innertag inner m' => m' a) ->
   m a

data/examples/declaration/value/function/fancy-forall-1-out.hs

@@ -1,10 +1,10 @@
 magnify ::
   forall outertag innertag t outer inner m a.
-  ( forall x. Coercible (t m x) (m x),
-    forall m'.
+  ( forall x. Coercible (t m x) (m x)
+  , forall m'.
     HasReader outertag outer m' =>
-    HasReader innertag inner (t m'),
-    HasReader outertag outer m
+    HasReader innertag inner (t m')
+  , HasReader outertag outer m
   ) =>
   (forall m'. HasReader innertag inner m' => m' a) ->
   m a

data/examples/declaration/value/function/implicit-params-out.hs

@@ -8,8 +8,8 @@ sort = sortBy ?cmp
 
 sort' ::
   ( ?cmp ::
-      a -> a -> Bool,
-    ?foo :: Int
+      a -> a -> Bool
+  , ?foo :: Int
   ) =>
   [a] ->
   [a]

data/examples/declaration/value/function/list-comprehensions-out.hs

@@ -5,20 +5,20 @@ bar x y = [(a, b) | a <- x, even a, b <- y, a != b]
 barbaz x y z w =
   [ (a, b, c, d) -- Foo
   | a <-
-        x, -- Bar
-      b <- y, -- Baz
-      any even [a, b],
-      c <-
+      x -- Bar
+  , b <- y -- Baz
+  , any even [a, b]
+  , c <-
       z
-          * z ^ 2, -- Bar baz
-      d <-
+        * z ^ 2 -- Bar baz
+  , d <-
       w
-          + w, -- Baz bar
-      all
+        + w -- Baz bar
+  , all
       even
-        [ a,
-          b,
-          c,
-          d
+      [ a
+      , b
+      , c
+      , d
       ]
   ]

data/examples/declaration/value/function/parallel-comprehensions-complex-out.hs

@@ -1,20 +1,20 @@
 baz x y z w =
-  [ ( a,
-      b,
-      c,
-      d,
-      e,
-      f,
-      g,
-      h,
-      i,
-      j
+  [ ( a
+    , b
+    , c
+    , d
+    , e
+    , f
+    , g
+    , h
+    , i
+    , j
     )
   | a <- -- Foo 1
-        x, -- Foo 2
-      b <- -- Bar 1
-        y, -- Bar 2
-      a
+      x -- Foo 2
+  , b <- -- Bar 1
+      y -- Bar 2
+  , a
       `mod` b -- Value
       == 0
   | c <- -- Baz 1
@@ -28,8 +28,8 @@ baz x y z w =
   | h <- z + z * w ^ 2 -- Bar foo
   | i <- -- Bar bar 1
       a
-          + b, -- Bar bar 2
+        + b -- Bar bar 2
         -- Bar bar 3
-      j <- -- Bar baz 1
+  , j <- -- Bar baz 1
       a + b -- Bar baz 2
   ]

data/examples/declaration/value/function/pattern/multiline-case-pattern-out.hs

@@ -1,12 +1,12 @@
 readerBench doc name =
   runPure $ case (getReader name, getWriter name) of
-    ( Right (TextReader r, rexts),
-      Right (TextWriter w, wexts)
+    ( Right (TextReader r, rexts)
+      , Right (TextWriter w, wexts)
       ) -> undefined
 
 f xs = case xs of
-  [ a,
-    b
+  [ a
+    , b
     ] -> a + b
 
 g xs = case xs of

data/examples/declaration/value/function/pattern/record-patterns-out.hs

@@ -13,7 +13,7 @@ baz Boom {boom = b, ..} = b
 quux :: Boom -> Int
 quux
   Boom
-    { boom = a,
-      foom = b,
-      ..
+    { boom = a
+    , foom = b
+    , ..
     } = a + b

data/examples/declaration/value/function/record/constructors-out.hs

@@ -2,8 +2,8 @@ foo = Foo {a = 3}
 
 bar =
   Bar
-    { abc = foo,
-      def = Foo {a = 10}
+    { abc = foo
+    , def = Foo {a = 10}
     }
 
 baz = Baz {}
@@ -12,20 +12,20 @@ sym = Foo {(+) = 3}
 
 aLongVariableName =
   ALongRecordName
-    { short = baz,
-      aLongRecordFieldName =
+    { short = baz
+    , aLongRecordFieldName =
         YetAnotherLongRecordName
           { yetAnotherLongRecordFieldName = "a long string"
-          },
-      aLongRecordFieldName2 =
+          }
+    , aLongRecordFieldName2 =
         Just
           YetAnotherLongRecordName
-            { yetAnotherLongRecordFieldName = "a long string",
-              yetAnotherLongRecordFieldName =
+            { yetAnotherLongRecordFieldName = "a long string"
+            , yetAnotherLongRecordFieldName =
                 Just
                   "a long string"
-            },
-      aLongRecordFieldName3 = do
+            }
+    , aLongRecordFieldName3 = do
         foo
         bar
     }

data/examples/declaration/value/function/record/updaters-out.hs

@@ -2,8 +2,8 @@ foo x = x {a = 3}
 
 bar x =
   x
-    { abc = foo,
-      def = Foo {a = 10}
+    { abc = foo
+    , def = Foo {a = 10}
     }
 
 baz x = x {}

data/examples/declaration/value/function/record/wildcards-out.hs

@@ -5,10 +5,10 @@ foo x y = Foo {x, y}
 
 bar x y z =
   Bar
-    { x,
-      y,
-      z,
-      ..
+    { x
+    , y
+    , z
+    , ..
     }
 
 baz = Baz {..}

data/examples/declaration/value/function/static-pointers-out.hs

@@ -6,9 +6,9 @@ foo = static 5
 bar :: StaticPtr [Int]
 bar =
   static
-    [ 1,
-      2,
-      3
+    [ 1
+    , 2
+    , 3
     ]
 
 baz :: StaticPtr Bool

data/examples/declaration/value/function/tuples-out.hs

@@ -1,14 +1,14 @@
 foo = (1, 2, 3)
 
 bar =
-  ( 1,
-    2,
-    3
+  ( 1
+  , 2
+  , 3
   )
 
 handleStuff =
   ( let foo = foo
-     in foo,
-    let bar = bar
+     in foo
+  , let bar = bar
      in bar
   )

data/examples/declaration/value/function/unboxed-tuples-out.hs

@@ -4,7 +4,7 @@ foo = (# 1, 2, 3 #)
 
 bar =
   (#
-    1,
-    2,
-    3
+    1
+    , 2
+    , 3
   #)

data/examples/declaration/value/other/comments-get-before-op-out.hs

@@ -1,9 +1,9 @@
 main :: IO ()
 main = do
   migrateSchema
-    [ migration1,
-      migration1,
-      migration3
+    [ migration1
+    , migration1
+    , migration3
     -- When adding migrations here, don't forget to update
     -- 'schemaVersion' in Galley.Data
     ]

data/examples/declaration/value/other/line-multi-line-out.hs

@@ -1,6 +1,6 @@
 x :: [Int]
 x =
-  [ 1,
-    2,
-    somethingSomething 3
+  [ 1
+  , 2
+  , somethingSomething 3
   ]

data/examples/declaration/value/pattern-synonyms/bidirectional-out.hs

@@ -6,8 +6,8 @@ pattern Arrow t1 t2 = App "->" [t1, t2]
 pattern Arrow {t1, t2} = App "->" [t1, t2]
 
 pattern Arrow
-  { t1,
-    t2
+  { t1
+  , t2
   } =
   App "->" [t1, t2]
 

data/examples/declaration/value/pattern-synonyms/unidirectional-out.hs

@@ -12,8 +12,8 @@ pattern FirstTwo {x, y} <-
   x : (y : xs)
 
 pattern FirstTwo'
-  { x,
-    y
+  { x
+  , y
   } <-
   x : (y : xs)
 

data/examples/declaration/warning/warning-multiline-out.hs

@@ -1,8 +1,8 @@
 {-# WARNING
-  test,
-  foo
-  [ "These are bad functions",
-    "Really bad!"
+  test
+  , foo
+  [ "These are bad functions"
+  , "Really bad!"
   ]
   #-}
 test :: IO ()

data/examples/import/explicit-imports-out.hs

@@ -1,12 +1,12 @@
 import qualified MegaModule as M
-  ( Either,
-    Maybe (Just, Nothing),
-    MaybeT (..),
-    Monad (return, (>>), (>>=)),
-    MonadBaseControl,
-    join,
-    liftIO,
-    void,
-    (<<<),
-    (>>>),
+  ( Either
+  , Maybe (Just, Nothing)
+  , MaybeT (..)
+  , Monad (return, (>>), (>>=))
+  , MonadBaseControl
+  , join
+  , liftIO
+  , void
+  , (<<<)
+  , (>>>)
   )

data/examples/import/explicit-imports-with-comments-out.hs

@@ -1,7 +1,7 @@
 import qualified MegaModule as M
   ( -- (1)
     -- (2)
-    Either, -- (3)
-    (<<<),
-    (>>>),
+    Either -- (3)
+  , (<<<)
+  , (>>>)
   )

data/examples/import/misc-out.hs

@@ -1,5 +1,5 @@
 import A hiding
-  ( foobarbazqux,
+  ( foobarbazqux
   )
 import {-# SOURCE #-} safe qualified Module as M hiding (a, b, c, d, e, f)
 import Name hiding ()

data/examples/import/nested-explicit-imports-out.hs

@@ -1,10 +1,10 @@
 import qualified MegaModule as M
-  ( Either,
-    Monad
-      ( return,
-        (>>),
-        (>>=)
-      ),
-    (<<<),
-    (>>>),
+  ( Either
+  , Monad
+      ( return
+      , (>>)
+      , (>>=)
+      )
+  , (<<<)
+  , (>>>)
   )

data/examples/module-header/multiline-out.hs

@@ -1,6 +1,6 @@
 module Foo
-  ( foo,
-    bar,
-    baz,
+  ( foo
+  , bar
+  , baz
   )
 where

data/examples/module-header/multiline-with-comments-out.hs

@@ -4,18 +4,18 @@
 -- | Header.
 module My.Module
   ( -- * Something
-    foo,
-    bar,
+    foo
+  , bar
 
     -- * Another thing
-    (<?>),
-    {- some other thing -} foo2, -- yet another
-    foo3, -- third one
-    baz,
-    bar2, -- a multiline comment
+  , (<?>)
+  , {- some other thing -} foo2 -- yet another
+  , foo3 -- third one
+  , baz
+  , bar2 -- a multiline comment
   -- the second line
-    bar3,
-    module Foo.Bar.Baz,
+  , bar3
+  , module Foo.Bar.Baz
   )
 where
 

data/examples/module-header/multiline2-out.hs

@@ -1,6 +1,6 @@
 module Foo
-  ( foo,
-    bar,
-    baz,
+  ( foo
+  , bar
+  , baz
   )
 where

data/examples/module-header/named-section-out.hs

@@ -3,8 +3,8 @@ module Magic
     -- $explanation
 
     -- ** Another level
-    foo,
-    bar,
+    foo
+  , bar
   )
 where
 

data/examples/module-header/warning-pragma-list-multiline-out.hs

@@ -1,11 +1,11 @@
 module Test
   {-# DEPRECATED
-    [ "This module is deprecated.",
-      "Please use OtherModule instead."
+    [ "This module is deprecated."
+    , "Please use OtherModule instead."
     ]
     #-}
-  ( foo,
-    bar,
-    baz,
+  ( foo
+  , bar
+  , baz
   )
 where

data/examples/other/comment-inside-construct-out.hs

@@ -1,8 +1,8 @@
 xs =
-  [ outer list item,
-    [ inner list first item,
-      inner list second item
+  [ outer list item
+  , [ inner list first item
+    , inner list second item
     -- inner list last item commented
-    ],
-    outer list item
+    ]
+  , outer list item
   ]

data/examples/other/cpp/shifted-out.hs

@@ -15,7 +15,7 @@ sinkData h compression = do
 #endif
   return
     DataDescriptor
-      { ddCRC32 = fromIntegral crc32,
-        ddCompressedSize = compressedSize,
-        ddUncompressedSize = uncompressedSize
+      { ddCRC32 = fromIntegral crc32
+      , ddCompressedSize = compressedSize
+      , ddUncompressedSize = uncompressedSize
       }

data/examples/other/merging-comments-out.hs

@@ -2,9 +2,9 @@ foo xs = baz
   where
     bar =
       catMaybes
-        [ lookup langKey gets, -- 1
-          lookup langKey cookies, -- 2
-          lookupText langKey session -- 3
+        [ lookup langKey gets -- 1
+        , lookup langKey cookies -- 2
+        , lookupText langKey session -- 3
         ]
         ++ xs -- 4
 

data/examples/other/pragma-sorting-out.hs

@@ -6,6 +6,6 @@
 {-# LANGUAGE NoMonoLocalBinds #-}
 
 module Foo
-  ( bar,
+  ( bar
   )
 where

region-tests/expected-result-all.hs

@@ -1,9 +1,9 @@
 {-# LANGUAGE LambdaCase #-}
 
 module Foo
-  ( foo,
-    bar,
-    baz,
+  ( foo
+  , bar
+  , baz
   )
 where
 

src/Ormolu/Printer/Combinators.hs

@@ -294,9 +294,13 @@ brackets_ needBreaks open close style m = sitcc (vlayout singleLine multiLine)
       txt close
     multiLine = do
       txt open
-      if needBreaks
-        then newline >> inci m
-        else space >> sitcc m
+      let inci' =
+            if (style == S) || needBreaks
+              then inci
+              else id
+      inci' $ if needBreaks
+        then newline >> m
+        else space >> m
       newline
       inciIf (style == S) (txt close)
 
@@ -309,7 +313,7 @@ comma = txt ","
 
 -- | Delimiting combination with 'comma'. To be used with 'sep'.
 commaDel :: R ()
-commaDel = comma >> breakpoint
+commaDel = breakpoint' >> comma >> space
 
 -- | Print @=@. Do not use @'txt' "="@.
 equals :: R ()

src/Ormolu/Printer/Meat/Common.hs

@@ -127,7 +127,7 @@ p_infixDefHelper isInfix indentArgs name args =
       let parens' =
             if null ps
               then id
-              else parens N
+              else parens N . sitcc
       parens' $ do
         p0
         breakpoint

src/Ormolu/Printer/Meat/Declaration/Class.hs

@@ -82,7 +82,7 @@ p_classFundeps fdeps = unless (null fdeps) $ do
   breakpoint
   txt "|"
   space
-  inci $ sep commaDel (sitcc . located' p_funDep) fdeps
+  sep commaDel (sitcc . located' p_funDep) fdeps
 
 p_funDep :: FunDep (Located RdrName) -> R ()
 p_funDep (before, after) = do

src/Ormolu/Printer/Meat/Declaration/Rule.hs

@@ -55,7 +55,7 @@ p_ruleName (_, name) = atom $ (HsString NoSourceText name :: HsLit GhcPs)
 p_ruleBndr :: RuleBndr GhcPs -> R ()
 p_ruleBndr = \case
   RuleBndr NoExtField x -> p_rdrName x
-  RuleBndrSig NoExtField x hswc -> parens N $ do
+  RuleBndrSig NoExtField x hswc -> parens N . sitcc $ do
     p_rdrName x
     p_typeAscription hswc
   XRuleBndr x -> noExtCon x

src/Ormolu/Printer/Meat/Declaration/Value.hs

@@ -333,7 +333,7 @@ p_hsCmd = \case
     -- does. Open an issue and ping @yumiova if this ever occurs in output.
     notImplemented "HsCmdApp"
   HsCmdLam NoExtField mgroup -> p_matchGroup' cmdPlacement p_hsCmd Lambda mgroup
-  HsCmdPar NoExtField c -> parens N (located c p_hsCmd)
+  HsCmdPar NoExtField c -> parens N (sitcc $ located c p_hsCmd)
   HsCmdCase NoExtField e mgroup ->
     p_case cmdPlacement p_hsCmd e mgroup
   HsCmdIf NoExtField _ if' then' else' ->
@@ -627,7 +627,7 @@ p_hsExpr' s = \case
     space
     located e p_hsExpr
   HsPar NoExtField e ->
-    parens s (located e (dontUseBraces . p_hsExpr))
+    parens s (sitcc $ located e (dontUseBraces . p_hsExpr))
   SectionL NoExtField x op -> do
     located x p_hsExpr
     breakpoint
@@ -686,8 +686,7 @@ p_hsExpr' s = \case
                   (breakpoint >> txt "|" >> space)
                   p_seqBody
               p_seqBody =
-                sitcc
-                  . sep
+                sep
                   commaDel
                   (located' (sitcc . p_stmt))
               stmts = init xs
@@ -948,7 +947,7 @@ p_pat = \case
     txt "@"
     located pat p_pat
   ParPat NoExtField pat ->
-    located pat (parens S . p_pat)
+    located pat (parens S . sitcc . p_pat)
   BangPat NoExtField pat -> do
     txt "!"
     located pat p_pat

src/Ormolu/Printer/Meat/ImportExport.hs

@@ -13,7 +13,6 @@ import Control.Monad
 import GHC
 import Ormolu.Printer.Combinators
 import Ormolu.Printer.Meat.Common
-import Ormolu.Utils (RelativePos (..), attachRelativePos)
 
 p_hsmodExports :: [LIE GhcPs] -> R ()
 p_hsmodExports [] = do
@@ -21,12 +20,7 @@ p_hsmodExports [] = do
   breakpoint'
   txt ")"
 p_hsmodExports xs =
-  parens N $ do
-    layout <- getLayout
-    sep
-      breakpoint
-      (\(p, l) -> sitcc (located l (p_lie layout p)))
-      (attachRelativePos xs)
+  parens N (p_lies xs)
 
 p_hsmodImport :: Bool -> ImportDecl GhcPs -> R ()
 p_hsmodImport useQualifiedPost ImportDecl {..} = do
@@ -65,28 +59,32 @@ p_hsmodImport useQualifiedPost ImportDecl {..} = do
       Nothing -> return ()
       Just (_, L _ xs) -> do
         breakpoint
-        parens N $ do
-          layout <- getLayout
-          sep
-            breakpoint
-            (\(p, l) -> sitcc (located l (p_lie layout p)))
-            (attachRelativePos xs)
+        parens N (p_lies xs)
     newline
 p_hsmodImport _ (XImportDecl x) = noExtCon x
 
-p_lie :: Layout -> RelativePos -> IE GhcPs -> R ()
-p_lie encLayout relativePos = \case
-  IEVar NoExtField l1 -> do
+p_lies :: [LIE GhcPs] -> R ()
+p_lies = go True True
+  where
+    go _ _ [] = return ()
+    go isFirstElement isFirstItem (x:xs)= do
+      let thisIsItem = isIEItem (unLoc x)
+      when (thisIsItem && not isFirstItem) $
+        comma >> space
+      inci $ located x (p_lie isFirstElement)
+      unless (null xs) breakpoint'
+      go False (if thisIsItem then False else isFirstItem) xs
+
+p_lie :: Bool -> IE GhcPs -> R ()
+p_lie isFirstElement = \case
+  IEVar NoExtField l1 ->
     located l1 p_ieWrappedName
-    p_comma
-  IEThingAbs NoExtField l1 -> do
+  IEThingAbs NoExtField l1 ->
     located l1 p_ieWrappedName
-    p_comma
   IEThingAll NoExtField l1 -> do
     located l1 p_ieWrappedName
     space
     txt "(..)"
-    p_comma
   IEThingWith NoExtField l1 w xs _ -> sitcc $ do
     located l1 p_ieWrappedName
     breakpoint
@@ -99,28 +97,21 @@ p_lie encLayout relativePos = \case
           IEWildcard n ->
             let (before, after) = splitAt n names
              in before ++ [txt ".."] ++ after
-    p_comma
-  IEModuleContents NoExtField l1 -> do
+  IEModuleContents NoExtField l1 ->
     located l1 p_hsmodName
-    p_comma
   IEGroup NoExtField n str -> do
-    case relativePos of
-      SinglePos -> return ()
-      FirstPos -> return ()
-      MiddlePos -> newline
-      LastPos -> newline
+    unless isFirstElement (newline >> newline)
     p_hsDocString (Asterisk n) False (noLoc str)
   IEDoc NoExtField str ->
     p_hsDocString Pipe False (noLoc str)
   IEDocNamed NoExtField str -> p_hsDocName str
   XIE x -> noExtCon x
-  where
-    p_comma =
-      case encLayout of
-        SingleLine ->
-          case relativePos of
-            SinglePos -> return ()
-            FirstPos -> comma
-            MiddlePos -> comma
-            LastPos -> return ()
-        MultiLine -> comma
+
+isIEItem :: IE GhcPs -> Bool
+isIEItem = \case
+  IEVar {} -> True
+  IEThingAbs {} -> True
+  IEThingAll {} -> True
+  IEThingWith {} -> True
+  IEModuleContents {} -> True
+  _ -> False

src/Ormolu/Printer/Meat/Type.hs

@@ -107,7 +107,7 @@ p_hsType' multilineArgs docStyle = \case
       let opTree = OpBranch (tyOpTree x) op (tyOpTree y)
        in p_tyOpTree (reassociateOpTree Just opTree)
   HsParTy NoExtField t ->
-    parens N (located t p_hsType)
+    parens N (sitcc $ located t p_hsType)
   HsIParamTy NoExtField n t -> sitcc $ do
     located n atom
     space
@@ -198,7 +198,7 @@ p_hsTyVarBndr :: HsTyVarBndr GhcPs -> R ()
 p_hsTyVarBndr = \case
   UserTyVar NoExtField x ->
     p_rdrName x
-  KindedTyVar NoExtField l k -> parens N $ do
+  KindedTyVar NoExtField l k -> parens N . sitcc $ do
     located l atom
     space
     txt "::"