@@ -1,36 +1,43 @@
1−{-# LANGUAGE LambdaCase #-}
1+{-# LANGUAGE LambdaCase #-}
2+{-# LANGUAGE MultiWayIf #-}
23{-# LANGUAGE OverloadedStrings #-}
3−{-# LANGUAGE RecordWildCards #-}
4+{-# LANGUAGE RecordWildCards #-}
5+{-# LANGUAGE TypeApplications #-}
46
57module Ormolu.Printer.Meat.Declaration.Value
6− ( p_valDecl
7− , p_pat
8− , p_hsExpr
9− , p_hsSplice
8+ ( p_valDecl,
9+ p_pat,
10+ p_hsExpr,
11+ p_hsSplice,
12+ p_stringLit,
1013 )
1114where
1215
13−import Ormolu.Printer.Internal
1416import Bag (bagToList)
1517import BasicTypes
1618import Control.Monad
19+import Ctype (is_space)
1720import Data.Bool (bool)
1821import Data.Char (isPunctuation, isSymbol)
1922import Data.Data hiding (Infix, Prefix)
23+import Data.Functor ((<&>))
2024import Data.List (intersperse, sortOn)
25+import Data.List.NonEmpty (NonEmpty (..), (<|))
26+import qualified Data.List.NonEmpty as NE
2127import Data.Text (Text)
28+import qualified Data.Text as Text
2229import GHC
30+import OccName (occNameString)
2331import Ormolu.Printer.Combinators
32+import Ormolu.Printer.Internal
2433import Ormolu.Printer.Meat.Common
34+import {-# SOURCE #-} Ormolu.Printer.Meat.Declaration
2535import Ormolu.Printer.Meat.Declaration.Signature
2636import Ormolu.Printer.Meat.Type
37+import Ormolu.Printer.Operators
2738import Ormolu.Utils
28−import Outputable (Outputable (..))
29−import RdrName (rdrNameOcc)
30−import SrcLoc (combineSrcSpans, isOneLineSpan)
31−import qualified Data.List.NonEmpty as NE
32−import {-# SOURCE #-} Ormolu.Printer.Meat.Declaration
3339
40+-- | Style of a group of equations.
3441data MatchGroupStyle
3542 = Function (Located RdrName)
3643 | PatternBind
@@ -38,55 +45,62 @@ data MatchGroupStyle
3845 | Lambda
3946 | LambdaCase
4047
48+-- | Style of equations in a group.
4149data GroupStyle
4250 = EqualSign
4351 | RightArrow
4452
4553-- | Expression placement. This marks the places where expressions that
4654-- implement handing forms may use them.
47−
4855data Placement
49− = Normal -- ^ Multi-line layout should cause
50− -- insertion of a newline and indentation
51− -- bump
52− | Hanging -- ^ Expressions that have hanging form
53− -- should use it and avoid bumping one level
54− -- of indentation
56+ = -- | Multi-line layout should cause
57+ -- insertion of a newline and indentation
58+ -- bump
59+ Normal
60+ | -- | Expressions that have hanging form
61+ -- should use it and avoid bumping one level
62+ -- of indentation
63+ Hanging
64+ deriving (Eq, Show)
5565
5666p_valDecl :: HsBindLR GhcPs GhcPs -> R ()
5767p_valDecl = \case
58− FunBind NoExt funId funMatches _ _ -> p_funBind funId funMatches
59− PatBind NoExt pat grhss _ -> p_match PatternBind False NoSrcStrict [pat] grhss
68+ FunBind NoExtField funId funMatches _ _ -> p_funBind funId funMatches
69+ PatBind NoExtField pat grhss _ -> p_match PatternBind False NoSrcStrict [pat] grhss
6070 VarBind {} -> notImplemented "VarBinds" -- introduced by the type checker
6171 AbsBinds {} -> notImplemented "AbsBinds" -- introduced by the type checker
62− PatSynBind NoExt psb -> p_patSynBind psb
63− XHsBindsLR NoExt -> notImplemented "XHsBindsLR"
72+ PatSynBind NoExtField psb -> p_patSynBind psb
73+ XHsBindsLR x -> noExtCon x
6474
65−p_funBind
66− :: Located RdrName
67− -> MatchGroup GhcPs (LHsExpr GhcPs)
68− -> R ()
75+p_funBind ::
76+ Located RdrName ->
77+ MatchGroup GhcPs (LHsExpr GhcPs) ->
78+ R ()
6979p_funBind name = p_matchGroup (Function name)
7080
71−p_matchGroup
72− :: MatchGroupStyle
73− -> MatchGroup GhcPs (LHsExpr GhcPs)
74− -> R ()
81+p_matchGroup ::
82+ MatchGroupStyle ->
83+ MatchGroup GhcPs (LHsExpr GhcPs) ->
84+ R ()
7585p_matchGroup = p_matchGroup' exprPlacement p_hsExpr
7686
77−p_matchGroup'
78− :: Data body
79− => (body -> Placement)
80− -> (body -> R ())
81− -> MatchGroupStyle
82− -> MatchGroup GhcPs (Located body)
83− -> R ()
84−p_matchGroup' placer pretty style MG {..} = do
87+p_matchGroup' ::
88+ Data body =>
89+ -- | How to get body placement
90+ (body -> Placement) ->
91+ -- | How to print body
92+ (body -> R ()) ->
93+ -- | Style of this group of equations
94+ MatchGroupStyle ->
95+ -- | Match group
96+ MatchGroup GhcPs (Located body) ->
97+ R ()
98+p_matchGroup' placer render style MG {..} = do
8599 let ob = case style of
86100 Case -> id
87101 LambdaCase -> id
88102 _ -> dontUseBraces
89− -- NOTE since we are forcing braces on 'sepSemi' based on 'ob', we have to
103+ -- Since we are forcing braces on 'sepSemi' based on 'ob', we have to
90104 -- restore the brace state inside the sepsemi.
91105 ub <- bool dontUseBraces useBraces <$> canUseBraces
92106 ob $ sepSemi (located' (ub . p_Match)) (unLoc mg_alts)
@@ -94,14 +108,14 @@ p_matchGroup' placer pretty style MG {..} = do
94108 p_Match m@Match {..} =
95109 p_match'
96110 placer
97− pretty
111+ render
98112 (adjustMatchGroupStyle m style)
99113 (isInfixMatch m)
100114 (matchStrictness m)
101115 m_pats
102116 m_grhss
103− p_Match _ = notImplemented "XMatch"
104−p_matchGroup' _ _ _ (XMatchGroup NoExt) = notImplemented "XMatchGroup"
117+ p_Match (XMatch x) = noExtCon x
118+p_matchGroup' _ _ _ (XMatchGroup x) = noExtCon x
105119
106120-- | Function id obtained through pattern matching on 'FunBind' should not
107121-- be used to print the actual equations because the different ‘RdrNames’
@@ -109,11 +123,10 @@ p_matchGroup' _ _ _ (XMatchGroup NoExt) = notImplemented "XMatchGroup"
109123-- and paretheses) associated with them. It is necessary to use per-equation
110124-- names obtained from 'm_ctxt' of 'Match'. This function replaces function
111125-- name inside of 'Function' accordingly.
112−
113−adjustMatchGroupStyle
114− :: Match GhcPs body
115− -> MatchGroupStyle
116− -> MatchGroupStyle
126+adjustMatchGroupStyle ::
127+ Match GhcPs body ->
128+ MatchGroupStyle ->
129+ MatchGroupStyle
117130adjustMatchGroupStyle m = \case
118131 Function _ -> (Function . mc_fun . m_ctxt) m
119132 style -> style
@@ -121,31 +134,43 @@ adjustMatchGroupStyle m = \case
121134matchStrictness :: Match id body -> SrcStrictness
122135matchStrictness match =
123136 case m_ctxt match of
124− FunRhs{mc_strictness=s} -> s
137+ FunRhs {mc_strictness = s} -> s
125138 _ -> NoSrcStrict
126139
127−p_match
128− :: MatchGroupStyle
129− -> Bool -- ^ Is this an infix match?
130− -> SrcStrictness -- ^ Strictness prefix (FunBind)
131− -> [LPat GhcPs]
132− -> GRHSs GhcPs (LHsExpr GhcPs)
133− -> R ()
140+p_match ::
141+ -- | Style of the group
142+ MatchGroupStyle ->
143+ -- | Is this an infix match?
144+ Bool ->
145+ -- | Strictness prefix (FunBind)
146+ SrcStrictness ->
147+ -- | Argument patterns
148+ [LPat GhcPs] ->
149+ -- | Equations
150+ GRHSs GhcPs (LHsExpr GhcPs) ->
151+ R ()
134152p_match = p_match' exprPlacement p_hsExpr
135153
136−p_match'
137− :: Data body
138− => (body -> Placement)
139− -> (body -> R ())
140− -> MatchGroupStyle
141− -> Bool -- ^ Is this an infix match?
142− -> SrcStrictness -- ^ Strictness prefix (FunBind)
143− -> [LPat GhcPs]
144− -> GRHSs GhcPs (Located body)
145− -> R ()
146−p_match' placer pretty style isInfix strictness m_pats m_grhss = do
147− -- NOTE Normally, since patterns may be placed in a multi-line layout, it
148− -- is necessary to bump indentation for the pattern group so it's more
154+p_match' ::
155+ Data body =>
156+ -- | How to get body placement
157+ (body -> Placement) ->
158+ -- | How to print body
159+ (body -> R ()) ->
160+ -- | Style of this group of equations
161+ MatchGroupStyle ->
162+ -- | Is this an infix match?
163+ Bool ->
164+ -- | Strictness prefix (FunBind)
165+ SrcStrictness ->
166+ -- | Argument patterns
167+ [LPat GhcPs] ->
168+ -- | Equations
169+ GRHSs GhcPs (Located body) ->
170+ R ()
171+p_match' placer render style isInfix strictness m_pats GRHSs {..} = do
172+ -- Normally, since patterns may be placed in a multi-line layout, it is
173+ -- necessary to bump indentation for the pattern group so it's more
149174 -- indented than function name. This in turn means that indentation for
150175 -- the body should also be bumped. Normally this would mean that bodies
151176 -- would start with two indentation steps applied, which is ugly, so we
@@ -155,23 +180,24 @@ p_match' placer pretty style isInfix strictness m_pats m_grhss = do
155180 NoSrcStrict -> return ()
156181 SrcStrict -> txt "!"
157182 SrcLazy -> txt "~"
158− inci' <- case NE.nonEmpty m_pats of
159− Nothing -> id <$ case style of
160− Function name -> p_rdrName name
161− _ -> return ()
183+ indentBody <- case NE.nonEmpty m_pats of
184+ Nothing ->
185+ False <$ case style of
186+ Function name -> p_rdrName name
187+ _ -> return ()
162188 Just ne_pats -> do
163− let combinedSpans = combineSrcSpans' $
164− getLoc <$> ne_pats
165− inci' = if isOneLineSpan combinedSpans
166− then id
167− else inci
189+ let combinedSpans = case style of
190+ Function name -> combineSrcSpans (getLoc name) patSpans
191+ _ -> patSpans
192+ patSpans = combineSrcSpans' (getLoc <$> ne_pats)
193+ indentBody = not (isOneLineSpan combinedSpans)
168194 switchLayout [combinedSpans] $ do
169195 let stdCase = sep breakpoint (located' p_pat) m_pats
170196 case style of
171197 Function name ->
172198 p_infixDefHelper
173199 isInfix
174− inci'
200+ indentBody
175201 (p_rdrName name)
176202 (located' p_pat <$> m_pats)
177203 PatternBind -> stdCase
@@ -182,49 +208,44 @@ p_match' placer pretty style isInfix strictness m_pats m_grhss = do
182208 BangPat _ _ -> True
183209 SplicePat _ _ -> True
184210 _ -> False
185− txt (if needsSpace then "\\ " else "\\")
186− stdCase
211+ txt "\\"
212+ when needsSpace space
213+ sitcc stdCase
187214 LambdaCase -> stdCase
188− return inci'
189− let
190− -- Calculate position of end of patterns. This is useful when we decide
191− -- about putting certain constructions in hanging positions.
192− endOfPats = case NE.nonEmpty m_pats of
193− Nothing -> case style of
194− Function name -> (Just . srcSpanEnd . getLoc) name
195− _ -> Nothing
196− Just pats -> (Just . srcSpanEnd . getLoc . NE.last) pats
197− isCase = \case
198− Case -> True
199− LambdaCase -> True
200− _ -> False
201− let GRHSs {..} = m_grhss
215+ return indentBody
216+ let -- Calculate position of end of patterns. This is useful when we decide
217+ -- about putting certain constructions in hanging positions.
218+ endOfPats = case NE.nonEmpty m_pats of
219+ Nothing -> case style of
220+ Function name -> Just (getLoc name)
221+ _ -> Nothing
222+ Just pats -> (Just . getLoc . NE.last) pats
223+ isCase = \case
224+ Case -> True
225+ LambdaCase -> True
226+ _ -> False
202227 hasGuards = withGuards grhssGRHSs
203− unless (length grhssGRHSs > 1) $ do
204− case style of
205− Function _ | hasGuards -> return ()
206− Function _ -> txt " ="
207− PatternBind -> txt " ="
208− s | isCase s && hasGuards -> return ()
209− _ -> txt " ->"
210− let grhssSpan = combineSrcSpans' $
211− getGRHSSpan . unLoc <$> NE.fromList grhssGRHSs
212− patGrhssSpan = maybe grhssSpan
213− (combineSrcSpans grhssSpan . srcLocSpan) endOfPats
228+ grhssSpan =
229+ combineSrcSpans' $
230+ getGRHSSpan . unLoc <$> NE.fromList grhssGRHSs
231+ patGrhssSpan =
232+ maybe
233+ grhssSpan
234+ (combineSrcSpans grhssSpan . srcLocSpan . srcSpanEnd)
235+ endOfPats
214236 placement =
215237 case endOfPats of
216238 Nothing -> blockPlacement placer grhssGRHSs
217239 Just spn ->
218− if isOneLineSpan
219− (mkSrcSpan spn (srcSpanStart grhssSpan))
240+ if onTheSameLine spn grhssSpan
220241 then blockPlacement placer grhssGRHSs
221242 else Normal
222243 p_body = do
223244 let groupStyle =
224245 if isCase style && hasGuards
225− then RightArrow
226− else EqualSign
227− sep newline (located' (p_grhs' pretty groupStyle)) grhssGRHSs
246+ then RightArrow
247+ else EqualSign
248+ sep newline (located' (p_grhs' placer render groupStyle)) grhssGRHSs
228249 p_where = do
229250 let whereIsEmpty = GHC.isEmptyLocalBindsPR (unLoc grhssLocalBinds)
230251 unless (GHC.eqEmptyLocalBinds (unLoc grhssLocalBinds)) $ do
@@ -232,166 +253,211 @@ p_match' placer pretty style isInfix strictness m_pats m_grhss = do
232253 txt "where"
233254 unless whereIsEmpty breakpoint
234255 inci $ located grhssLocalBinds p_hsLocalBinds
235− inci' $ do
256+ inciIf indentBody $ do
257+ unless (length grhssGRHSs > 1) $
258+ case style of
259+ Function _ | hasGuards -> return ()
260+ Function _ -> space >> inci equals
261+ PatternBind -> space >> inci equals
262+ s | isCase s && hasGuards -> return ()
263+ _ -> space >> txt "->"
236264 switchLayout [patGrhssSpan] $
237265 placeHanging placement p_body
238266 inci p_where
267+p_match' _ _ _ _ _ _ (XGRHSs x) = noExtCon x
239268
240269p_grhs :: GroupStyle -> GRHS GhcPs (LHsExpr GhcPs) -> R ()
241−p_grhs = p_grhs' p_hsExpr
242−
243−p_grhs'
244− :: Data body
245− => (body -> R ())
246− -> GroupStyle
247− -> GRHS GhcPs (Located body)
248− -> R ()
249−p_grhs' pretty style (GRHS NoExt guards body) =
270+p_grhs = p_grhs' exprPlacement p_hsExpr
271+
272+p_grhs' ::
273+ Data body =>
274+ -- | How to get body placement
275+ (body -> Placement) ->
276+ -- | How to print body
277+ (body -> R ()) ->
278+ GroupStyle ->
279+ GRHS GhcPs (Located body) ->
280+ R ()
281+p_grhs' placer render style (GRHS NoExtField guards body) =
250282 case guards of
251283 [] -> p_body
252284 xs -> do
253− txt "| "
254− sitcc (sep (comma >> breakpoint) (sitcc . located' p_stmt) xs)
285+ txt "|"
255286 space
256− txt $ case style of
257− EqualSign -> "="
258− RightArrow -> "->"
259− breakpoint
260− inci p_body
287+ sitcc (sep commaDel (sitcc . located' p_stmt) xs)
288+ space
289+ inci $ case style of
290+ EqualSign -> equals
291+ RightArrow -> txt "->"
292+ placeHanging placement p_body
261293 where
262− p_body = located body pretty
263−p_grhs' _ _ (XGRHS NoExt) = notImplemented "XGRHS"
294+ placement =
295+ case endOfGuards of
296+ Nothing -> placer (unLoc body)
297+ Just spn ->
298+ if onTheSameLine spn (getLoc body)
299+ then placer (unLoc body)
300+ else Normal
301+ endOfGuards =
302+ case NE.nonEmpty guards of
303+ Nothing -> Nothing
304+ Just gs -> (Just . getLoc . NE.last) gs
305+ p_body = located body render
306+p_grhs' _ _ _ (XGRHS x) = noExtCon x
264307
265308p_hsCmd :: HsCmd GhcPs -> R ()
266309p_hsCmd = \case
267− HsCmdArrApp NoExt body input arrType _ -> do
310+ HsCmdArrApp NoExtField body input arrType _ -> do
268311 located body p_hsExpr
269− txt $ case arrType of
270− HsFirstOrderApp -> " -<"
271− HsHigherOrderApp -> " -<<"
272− placeHanging (exprPlacement (unLoc input)) $
273− located input p_hsExpr
274− HsCmdArrForm NoExt form Prefix _ cmds -> banana $ sitcc $ do
312+ breakpoint
313+ inci $ do
314+ case arrType of
315+ HsFirstOrderApp -> txt "-<"
316+ HsHigherOrderApp -> txt "-<<"
317+ placeHanging (exprPlacement (unLoc input)) $
318+ located input p_hsExpr
319+ HsCmdArrForm NoExtField form Prefix _ cmds -> banana $ do
275320 located form p_hsExpr
276321 unless (null cmds) $ do
277322 breakpoint
278323 inci (sequence_ (intersperse breakpoint (located' p_hsCmdTop <$> cmds)))
279− HsCmdArrForm NoExt form Infix _ [left, right] -> do
324+ HsCmdArrForm NoExtField form Infix _ [left, right] -> do
280325 located left p_hsCmdTop
281326 space
282327 located form p_hsExpr
283328 placeHanging (cmdTopPlacement (unLoc right)) $
284329 located right p_hsCmdTop
285− HsCmdArrForm NoExt _ Infix _ _ -> notImplemented "HsCmdArrForm"
330+ HsCmdArrForm NoExtField _ Infix _ _ -> notImplemented "HsCmdArrForm"
286331 HsCmdApp {} ->
287332 -- XXX Does this ever occur in the syntax tree? It does not seem like it
288333 -- does. Open an issue and ping @yumiova if this ever occurs in output.
289334 notImplemented "HsCmdApp"
290− HsCmdLam NoExt mgroup -> p_matchGroup' cmdPlacement p_hsCmd Lambda mgroup
291− HsCmdPar NoExt c -> parens (located c p_hsCmd)
292− HsCmdCase NoExt e mgroup -> do
293− txt "case "
294− located e p_hsExpr
295− txt " of"
296− breakpoint
297− inci (p_matchGroup' cmdPlacement p_hsCmd Case mgroup)
298− HsCmdIf NoExt _ if' then' else' -> do
299− txt "if "
300− located if' p_hsExpr
301− breakpoint
302− txt "then"
303− located then' $ \x -> do
304− breakpoint
305− inci (p_hsCmd x)
306− breakpoint
307− txt "else"
308− located else' $ \x -> do
309− breakpoint
310− inci (p_hsCmd x)
311− HsCmdLet NoExt localBinds c -> do
312− txt "let "
313− sitcc (located localBinds p_hsLocalBinds)
314− breakpoint
315− txt "in "
316− sitcc (located c p_hsCmd)
317− HsCmdDo NoExt es -> do
335+ HsCmdLam NoExtField mgroup -> p_matchGroup' cmdPlacement p_hsCmd Lambda mgroup
336+ HsCmdPar NoExtField c -> parens N (located c p_hsCmd)
337+ HsCmdCase NoExtField e mgroup ->
338+ p_case cmdPlacement p_hsCmd e mgroup
339+ HsCmdIf NoExtField _ if' then' else' ->
340+ p_if cmdPlacement p_hsCmd if' then' else'
341+ HsCmdLet NoExtField localBinds c ->
342+ p_let p_hsCmd localBinds c
343+ HsCmdDo NoExtField es -> do
318344 txt "do"
319345 newline
320− inci (located es (sitcc . sep newline (located' (sitcc . p_stmt' p_hsCmd))))
346+ inci . located es $
347+ sitcc . sep newline (sitcc . withSpacing (p_stmt' cmdPlacement p_hsCmd))
321348 HsCmdWrap {} -> notImplemented "HsCmdWrap"
322− XCmd {} -> notImplemented "XCmd"
349+ XCmd x -> noExtCon x
323350
324351p_hsCmdTop :: HsCmdTop GhcPs -> R ()
325352p_hsCmdTop = \case
326− HsCmdTop NoExt cmd -> located cmd p_hsCmd
327− XCmdTop {} -> notImplemented "XHsCmdTop"
353+ HsCmdTop NoExtField cmd -> located cmd p_hsCmd
354+ XCmdTop x -> noExtCon x
355+
356+-- | Render an expression preserving blank lines between such consecutive
357+-- expressions found in the original source code.
358+withSpacing ::
359+ -- | Rendering function
360+ (a -> R ()) ->
361+ -- | Entity to render
362+ Located a ->
363+ R ()
364+withSpacing f l = located l $ \x -> do
365+ case getLoc l of
366+ UnhelpfulSpan _ -> f x
367+ RealSrcSpan currentSpn -> do
368+ getSpanMark >>= \case
369+ -- Spacing before comments will be handled by the code
370+ -- that prints comments, so we just have to deal with
371+ -- blank lines between statements here.
372+ Just (StatementSpan lastSpn) ->
373+ if srcSpanStartLine currentSpn > srcSpanEndLine lastSpn + 1
374+ then newline
375+ else return ()
376+ _ -> return ()
377+ f x
378+ -- In some cases the (f x) expression may insert a new mark. We want
379+ -- to be careful not to override comment marks.
380+ getSpanMark >>= \case
381+ Just (HaddockSpan _ _) -> return ()
382+ Just (CommentSpan _) -> return ()
383+ _ -> setSpanMark (StatementSpan currentSpn)
328384
329385p_stmt :: Stmt GhcPs (LHsExpr GhcPs) -> R ()
330−p_stmt = p_stmt' p_hsExpr
331−
332−p_stmt'
333− :: Data body
334− => (body -> R ())
335− -> Stmt GhcPs (Located body)
336− -> R ()
337−p_stmt' pretty = \case
338− LastStmt NoExt body _ _ -> located body pretty
339− BindStmt NoExt l f _ _ -> do
340− located l p_pat
386+p_stmt = p_stmt' exprPlacement p_hsExpr
387+
388+p_stmt' ::
389+ Data body =>
390+ -- | Placer
391+ (body -> Placement) ->
392+ -- | Render
393+ (body -> R ()) ->
394+ -- | Statement to render
395+ Stmt GhcPs (Located body) ->
396+ R ()
397+p_stmt' placer render = \case
398+ LastStmt NoExtField body _ _ -> located body render
399+ BindStmt NoExtField p f _ _ -> do
400+ located p p_pat
341401 space
342402 txt "<-"
343− breakpoint
344− inci (located f pretty)
403+ let loc = getLoc p
404+ placement =
405+ case f of
406+ L l' x ->
407+ if isOneLineSpan
408+ (mkSrcSpan (srcSpanEnd loc) (srcSpanStart l'))
409+ then placer x
410+ else Normal
411+ switchLayout [loc, getLoc f] $
412+ placeHanging placement (located f render)
345413 ApplicativeStmt {} -> notImplemented "ApplicativeStmt" -- generated by renamer
346− BodyStmt NoExt body _ _ -> located body pretty
347− LetStmt NoExt binds -> do
348− txt "let "
414+ BodyStmt NoExtField body _ _ -> located body render
415+ LetStmt NoExtField binds -> do
416+ txt "let"
417+ space
349418 sitcc $ located binds p_hsLocalBinds
350419 ParStmt {} ->
351− -- NOTE 'ParStmt' should always be eliminated in 'gatherStmt' already,
352− -- such that it never occurs in 'p_stmt''. Consequently, handling it
353− -- here would be redundant.
420+ -- 'ParStmt' should always be eliminated in 'gatherStmt' already, such
421+ -- that it never occurs in 'p_stmt''. Consequently, handling it here
422+ -- would be redundant.
354423 notImplemented "ParStmt"
355− TransStmt {..} -> do
356− -- NOTE 'TransStmt' only needs to account for pretty printing itself,
357− -- since pretty printing of relevant statements (e.g., in 'trS_stmts')
358− -- is handled through 'gatherStmt'.
424+ TransStmt {..} ->
425+ -- 'TransStmt' only needs to account for render printing itself, since
426+ -- pretty printing of relevant statements (e.g., in 'trS_stmts') is
427+ -- handled through 'gatherStmt'.
359428 case (trS_form, trS_by) of
360− (ThenForm, Nothing) -> located trS_using $ \x -> do
429+ (ThenForm, Nothing) -> do
361430 txt "then"
362431 breakpoint
363− inci (p_hsExpr x)
432+ inci $ located trS_using p_hsExpr
364433 (ThenForm, Just e) -> do
365− located trS_using $ \x -> do
366− txt "then"
367− breakpoint
368− inci (p_hsExpr x)
434+ txt "then"
369435 breakpoint
370− located e $ \x -> do
371− txt "by"
372− breakpoint
373− inci (p_hsExpr x)
374− (GroupForm, Nothing) -> located trS_using $ \x -> do
436+ inci $ located trS_using p_hsExpr
437+ breakpoint
438+ txt "by"
439+ breakpoint
440+ inci $ located e p_hsExpr
441+ (GroupForm, Nothing) -> do
375442 txt "then group using"
376443 breakpoint
377− inci (p_hsExpr x)
444+ inci $ located trS_using p_hsExpr
378445 (GroupForm, Just e) -> do
379− located e $ \x -> do
380− txt "then group by"
381− breakpoint
382− inci (p_hsExpr x)
446+ txt "then group by"
383447 breakpoint
384− located trS_using $ \x -> do
385− txt "using"
386− breakpoint
387− inci (p_hsExpr x)
448+ inci $ located e p_hsExpr
449+ breakpoint
450+ txt "using"
451+ breakpoint
452+ inci $ located trS_using p_hsExpr
388453 RecStmt {..} -> do
389− txt "rec "
390− sitcc $ sepSemi (located' (p_stmt' pretty)) recS_stmts
391− XStmtLR {} -> notImplemented "XStmtLR"
454+ txt "rec"
455+ space
456+ sitcc $ sepSemi (withSpacing (p_stmt' placer render)) recS_stmts
457+ XStmtLR c -> noExtCon c
392458
393459gatherStmt :: ExprLStmt GhcPs -> [[ExprLStmt GhcPs]]
394−gatherStmt (L _ (ParStmt NoExt block _ _)) =
460+gatherStmt (L _ (ParStmt NoExtField block _ _)) =
395461 foldr ((<>) . gatherStmtBlock) [] block
396462gatherStmt (L s stmt@TransStmt {..}) =
397463 foldr liftAppend [] ((gatherStmt <$> trS_stmts) <> pure [[L s stmt]])
@@ -400,256 +466,337 @@ gatherStmt stmt = [[stmt]]
400466gatherStmtBlock :: ParStmtBlock GhcPs GhcPs -> [[ExprLStmt GhcPs]]
401467gatherStmtBlock (ParStmtBlock _ stmts _ _) =
402468 foldr (liftAppend . gatherStmt) [] stmts
403−gatherStmtBlock XParStmtBlock {} = notImplemented "XParStmtBlock"
469+gatherStmtBlock (XParStmtBlock x) = noExtCon x
404470
405471p_hsLocalBinds :: HsLocalBindsLR GhcPs GhcPs -> R ()
406472p_hsLocalBinds = \case
407− HsValBinds NoExt (ValBinds NoExt bag lsigs) -> do
408− let ssStart = either
409− (srcSpanStart . getLoc)
410− (srcSpanStart . getLoc)
411− items =
412− (Left <$> bagToList bag) ++ (Right <$> lsigs)
413− p_item (Left x) = located x p_valDecl
414− p_item (Right x) = located x p_sigDecl
415− sitcc $ sepSemi (useBraces . p_item) (sortOn ssStart items)
416− HsValBinds NoExt _ -> notImplemented "HsValBinds"
417− HsIPBinds NoExt (IPBinds NoExt xs) ->
473+ HsValBinds NoExtField (ValBinds NoExtField bag lsigs) -> do
474+ -- When in a single-line layout, there is a chance that the inner
475+ -- elements will also contain semicolons and they will confuse the
476+ -- parser. so we request braces around every element except the last.
477+ br <- layoutToBraces <$> getLayout
478+ let items =
479+ let injectLeft (L l x) = L l (Left x)
480+ injectRight (L l x) = L l (Right x)
481+ in (injectLeft <$> bagToList bag) ++ (injectRight <$> lsigs)
482+ positionToBracing = \case
483+ SinglePos -> id
484+ FirstPos -> br
485+ MiddlePos -> br
486+ LastPos -> id
487+ p_item' (p, item) =
488+ positionToBracing p $
489+ withSpacing (either p_valDecl p_sigDecl) item
490+ binds = sortOn (srcSpanStart . getLoc) items
491+ sitcc $ sepSemi p_item' (attachRelativePos binds)
492+ HsValBinds NoExtField _ -> notImplemented "HsValBinds"
493+ HsIPBinds NoExtField (IPBinds NoExtField xs) ->
418494 -- Second argument of IPBind is always Left before type-checking.
419− let p_ipBind (IPBind NoExt (Left name) expr) = do
495+ let p_ipBind (IPBind NoExtField (Left name) expr) = do
420496 atom name
421− txt " ="
497+ space
498+ equals
422499 breakpoint
423− dontUseBraces $ inci $ located expr p_hsExpr
424− p_ipBind _ = notImplemented "XHsIPBinds"
500+ useBraces $ inci $ located expr p_hsExpr
501+ p_ipBind (IPBind NoExtField (Right _) _) =
502+ -- Should only occur after the type checker
503+ notImplemented "IPBind _ (Right _) _"
504+ p_ipBind (XIPBind x) = noExtCon x
425505 in sepSemi (located' p_ipBind) xs
426− HsIPBinds NoExt _ -> notImplemented "HsIpBinds"
427− EmptyLocalBinds NoExt -> return ()
428− XHsLocalBindsLR _ -> notImplemented "XHsLocalBindsLR"
429−
430−p_hsRecField
431− :: (Data id, Outputable id)
432− => HsRecField' id (LHsExpr GhcPs)
433− -> R ()
434−p_hsRecField = \HsRecField {..} -> do
435− located hsRecFieldLbl atom
436− unless hsRecPun $ do
437− txt " ="
438− let placement = exprPlacement (unLoc hsRecFieldArg)
439− placeHanging placement $ located hsRecFieldArg p_hsExpr
506+ HsIPBinds NoExtField _ -> notImplemented "HsIpBinds"
507+ EmptyLocalBinds NoExtField -> return ()
508+ XHsLocalBindsLR x -> noExtCon x
440509
441−p_hsTupArg :: HsTupArg GhcPs -> R ()
442−p_hsTupArg = \case
443− Present NoExt x -> located x p_hsExpr
444− Missing NoExt -> pure ()
445− XTupArg {} -> notImplemented "XTupArg"
510+p_hsRecField ::
511+ HsRecField' RdrName (LHsExpr GhcPs) ->
512+ R ()
513+p_hsRecField HsRecField {..} = do
514+ p_rdrName hsRecFieldLbl
515+ unless hsRecPun $ do
516+ space
517+ equals
518+ let placement =
519+ if onTheSameLine (getLoc hsRecFieldLbl) (getLoc hsRecFieldArg)
520+ then exprPlacement (unLoc hsRecFieldArg)
521+ else Normal
522+ placeHanging placement (located hsRecFieldArg p_hsExpr)
446523
447524p_hsExpr :: HsExpr GhcPs -> R ()
448−p_hsExpr = \case
449− HsVar NoExt name -> p_rdrName name
450− HsUnboundVar NoExt _ -> notImplemented "HsUnboundVar"
451− HsConLikeOut NoExt _ -> notImplemented "HsConLikeOut"
452− HsRecFld NoExt x ->
525+p_hsExpr = p_hsExpr' N
526+
527+p_hsExpr' :: BracketStyle -> HsExpr GhcPs -> R ()
528+p_hsExpr' s = \case
529+ HsVar NoExtField name -> p_rdrName name
530+ HsUnboundVar NoExtField v -> atom (unboundVarOcc v)
531+ HsConLikeOut NoExtField _ -> notImplemented "HsConLikeOut"
532+ HsRecFld NoExtField x ->
453533 case x of
454− Unambiguous NoExt name -> p_rdrName name
455− Ambiguous NoExt name -> p_rdrName name
456− XAmbiguousFieldOcc NoExt -> notImplemented "XAmbiguousFieldOcc"
457− HsOverLabel NoExt _ v -> do
534+ Unambiguous NoExtField name -> p_rdrName name
535+ Ambiguous NoExtField name -> p_rdrName name
536+ XAmbiguousFieldOcc xx -> noExtCon xx
537+ HsOverLabel NoExtField _ v -> do
458538 txt "#"
459539 atom v
460− HsIPVar NoExt (HsIPName name) -> do
540+ HsIPVar NoExtField (HsIPName name) -> do
461541 txt "?"
462542 atom name
463− HsOverLit NoExt v -> atom (ol_val v)
464− HsLit NoExt lit -> atom lit
465− HsLam NoExt mgroup ->
543+ HsOverLit NoExtField v -> atom (ol_val v)
544+ HsLit NoExtField lit ->
545+ case lit of
546+ HsString (SourceText stxt) _ -> p_stringLit stxt
547+ HsStringPrim (SourceText stxt) _ -> p_stringLit stxt
548+ r -> atom r
549+ HsLam NoExtField mgroup ->
466550 p_matchGroup Lambda mgroup
467− HsLamCase NoExt mgroup -> do
551+ HsLamCase NoExtField mgroup -> do
468552 txt "\\case"
469− newline
553+ breakpoint
470554 inci (p_matchGroup LambdaCase mgroup)
471− HsApp NoExt f x -> sitcc $ do
472− located f p_hsExpr
473− -- Second argument can be a `do` or `case` block with `-XBlockArguments`.
474− placeHanging (exprPlacement (unLoc x)) $
475− located x p_hsExpr
476− HsAppType a e -> do
555+ HsApp NoExtField f x -> do
556+ let -- In order to format function applications with multiple parameters
557+ -- nicer, traverse the AST to gather the function and all the
558+ -- parameters together.
559+ gatherArgs f' knownArgs =
560+ case f' of
561+ L _ (HsApp _ l r) -> gatherArgs l (r <| knownArgs)
562+ _ -> (f', knownArgs)
563+ (func, args) = gatherArgs f (x :| [])
564+ -- We need to handle the last argument specially if it is a
565+ -- hanging construct, so separate it from the rest.
566+ (initp, lastp) = (NE.init args, NE.last args)
567+ initSpan =
568+ combineSrcSpans' $
569+ getLoc f :| [(srcLocSpan . srcSpanStart . getLoc) lastp]
570+ -- Hang the last argument only if the initial arguments span one
571+ -- line.
572+ placement =
573+ if isOneLineSpan initSpan
574+ then exprPlacement (unLoc lastp)
575+ else Normal
576+ -- If the last argument is not hanging, just separate every argument as
577+ -- usual. If it is hanging, print the initial arguments and hang the
578+ -- last one. Also, use braces around the every argument except the last
579+ -- one.
580+ case placement of
581+ Normal -> do
582+ let -- Usually we want to bump indentation for arguments for the
583+ -- sake of readability. However, when the function itself is a
584+ -- do-block or case expression it is not a good idea. It seems
585+ -- to be safe to always bump indentation when the function
586+ -- expression is parenthesised.
587+ doIndent =
588+ case func of
589+ L _ (HsPar NoExtField _) -> True
590+ L _ (HsAppType NoExtField _ _) -> True
591+ L _ (HsMultiIf NoExtField _) -> True
592+ L spn _ -> isOneLineSpan spn
593+ ub <-
594+ getLayout <&> \case
595+ SingleLine -> useBraces
596+ MultiLine -> id
597+ ub $ do
598+ located func (p_hsExpr' s)
599+ breakpoint
600+ inciIf doIndent $ sep breakpoint (located' p_hsExpr) initp
601+ inciIf doIndent $ do
602+ unless (null initp) breakpoint
603+ located lastp p_hsExpr
604+ Hanging -> do
605+ useBraces . switchLayout [initSpan] $ do
606+ located func (p_hsExpr' s)
607+ breakpoint
608+ sep breakpoint (located' p_hsExpr) initp
609+ placeHanging placement $
610+ located lastp p_hsExpr
611+ HsAppType NoExtField e a -> do
477612 located e p_hsExpr
478613 breakpoint
479614 inci $ do
480615 txt "@"
616+ -- Insert a space when the type is represented as a TH splice to avoid
617+ -- gluing @ and $ together.
618+ case unLoc (hswc_body a) of
619+ HsSpliceTy {} -> space
620+ _ -> return ()
481621 located (hswc_body a) p_hsType
482− OpApp NoExt x op y -> do
483− -- NOTE If the beginning of the first argument and the second argument
484− -- are on the same line, and the second argument has a hanging form, use
485− -- hanging placement.
486− let placement =
487− if isOneLineSpan
488− (mkSrcSpan (srcSpanStart (getLoc x)) (srcSpanStart (getLoc y)))
489− then exprPlacement (unLoc y)
490− else Normal
491− opWrapper = case unLoc op of
492− EWildPat NoExt -> backticks
493− _ -> id
494− ub <- vlayout
495− (return useBraces)
496− (return $ case placement of
497− Hanging -> useBraces
498− Normal -> dontUseBraces)
499− ub $ located x p_hsExpr
500− placeHanging placement $ do
501− located op (opWrapper . p_hsExpr)
502− space
503− located y p_hsExpr
504− NegApp NoExt e _ -> do
505− txt "- "
622+ OpApp NoExtField x op y -> do
623+ let opTree = OpBranch (exprOpTree x) op (exprOpTree y)
624+ p_exprOpTree s (reassociateOpTree getOpName opTree)
625+ NegApp NoExtField e _ -> do
626+ txt "-"
627+ space
506628 located e p_hsExpr
507− HsPar NoExt e -> parens (located e p_hsExpr)
508− SectionL NoExt x op -> do
629+ HsPar NoExtField e ->
630+ parens s (located e (dontUseBraces . p_hsExpr))
631+ SectionL NoExtField x op -> do
509632 located x p_hsExpr
510633 breakpoint
511634 inci (located op p_hsExpr)
512− SectionR NoExt op x -> do
635+ SectionR NoExtField op x -> do
513636 located op p_hsExpr
514− breakpoint
637+ useRecordDot' <- useRecordDot
638+ let isRecordDot' = isRecordDot (unLoc op) (getLoc x)
639+ unless (useRecordDot' && isRecordDot') breakpoint
515640 inci (located x p_hsExpr)
516− ExplicitTuple NoExt args boxity -> do
641+ ExplicitTuple NoExtField args boxity ->
517642 let isSection = any (isMissing . unLoc) args
518643 isMissing = \case
519− Missing NoExt -> True
644+ Missing NoExtField -> True
520645 _ -> False
521− let parens' =
646+ p_arg = \case
647+ Present NoExtField x -> located x p_hsExpr
648+ Missing NoExtField -> pure ()
649+ XTupArg x -> noExtCon x
650+ p_larg = sitcc . located' p_arg
651+ parens' =
522652 case boxity of
523653 Boxed -> parens
524654 Unboxed -> parensHash
525− if isSection
526− then switchLayout [] . parens' $
527− sep comma (located' p_hsTupArg) args
528− else switchLayout (getLoc <$> args) . parens' . sitcc $
529− sep (comma >> breakpoint) (sitcc . located' p_hsTupArg) args
530− ExplicitSum NoExt tag arity e ->
531− p_unboxedSum tag arity (located e p_hsExpr)
532− HsCase NoExt e mgroup -> do
533− txt "case "
534− located e p_hsExpr
535− txt " of"
536− breakpoint
537− inci (p_matchGroup Case mgroup)
538− HsIf NoExt _ if' then' else' -> do
539− txt "if "
540− located if' p_hsExpr
541− breakpoint
542− txt "then"
543− located then' $ \x -> do
544− breakpoint
545− inci (p_hsExpr x)
546− breakpoint
547− txt "else"
548− located else' $ \x -> do
549− breakpoint
550− inci (p_hsExpr x)
551− HsMultiIf NoExt guards -> do
655+ in if isSection
656+ then
657+ switchLayout [] . parens' s $
658+ sep comma p_larg args
659+ else
660+ switchLayout (getLoc <$> args) . parens' s $
661+ sep commaDel p_larg args
662+ ExplicitSum NoExtField tag arity e ->
663+ p_unboxedSum N tag arity (located e p_hsExpr)
664+ HsCase NoExtField e mgroup ->
665+ p_case exprPlacement p_hsExpr e mgroup
666+ HsIf NoExtField _ if' then' else' ->
667+ p_if exprPlacement p_hsExpr if' then' else'
668+ HsMultiIf NoExtField guards -> do
552669 txt "if"
553670 breakpoint
554− inci . sitcc $ sep newline (located' (p_grhs RightArrow)) guards
555− HsLet NoExt localBinds e -> do
556− txt "let "
557− sitcc (located localBinds p_hsLocalBinds)
558− vlayout space (newline >> space)
559− txt "in "
560− sitcc (located e p_hsExpr)
561− HsDo NoExt ctx es -> do
671+ inci . inci $ sep newline (located' (p_grhs RightArrow)) guards
672+ HsLet NoExtField localBinds e ->
673+ p_let p_hsExpr localBinds e
674+ HsDo NoExtField ctx es -> do
562675 let doBody header = do
563676 txt header
564677 breakpoint
565− ub <- vlayout (return useBraces) (return id)
566− inci $ sepSemi (located' (ub . p_stmt)) (unLoc es)
567− compBody = brackets $ located es $ \xs -> do
568− let p_parBody = sep
569− (breakpoint >> txt "| ")
570− p_seqBody
571− p_seqBody = sitcc . sep
572− (comma >> breakpoint)
573− (located' (sitcc . p_stmt))
678+ ub <- layoutToBraces <$> getLayout
679+ inci $
680+ sepSemi
681+ (ub . withSpacing (p_stmt' exprPlacement (p_hsExpr' S)))
682+ (unLoc es)
683+ compBody = brackets N . located es $ \xs -> do
684+ let p_parBody =
685+ sep
686+ (breakpoint >> txt "|" >> space)
687+ p_seqBody
688+ p_seqBody =
689+ sitcc
690+ . sep
691+ commaDel
692+ (located' (sitcc . p_stmt))
574693 stmts = init xs
575694 yield = last xs
576695 lists = foldr (liftAppend . gatherStmt) [] stmts
577696 located yield p_stmt
578697 breakpoint
579− txt "| "
698+ txt "|"
699+ space
580700 p_parBody lists
581701 case ctx of
582702 DoExpr -> doBody "do"
583703 MDoExpr -> doBody "mdo"
584704 ListComp -> compBody
585705 MonadComp -> notImplemented "MonadComp"
586− ArrowExpr -> notImplemented "ArrowExpr"
706+ ArrowExpr -> notImplemented "ArrowExpr"
587707 GhciStmtCtxt -> notImplemented "GhciStmtCtxt"
588708 PatGuard _ -> notImplemented "PatGuard"
589709 ParStmtCtxt _ -> notImplemented "ParStmtCtxt"
590710 TransStmtCtxt _ -> notImplemented "TransStmtCtxt"
591711 ExplicitList _ _ xs ->
592− brackets . sitcc $ sep (comma >> breakpoint) (sitcc . located' p_hsExpr) xs
712+ brackets s $
713+ sep commaDel (sitcc . located' p_hsExpr) xs
593714 RecordCon {..} -> do
594715 located rcon_con_name atom
595716 breakpoint
596717 let HsRecFields {..} = rcon_flds
597− fields = located' p_hsRecField <$> rec_flds
718+ updName f =
719+ (f :: HsRecField GhcPs (LHsExpr GhcPs))
720+ { hsRecFieldLbl = case unLoc $ hsRecFieldLbl f of
721+ FieldOcc _ n -> n
722+ XFieldOcc x -> noExtCon x
723+ }
724+ fields = located' (p_hsRecField . updName) <$> rec_flds
598725 dotdot =
599726 case rec_dotdot of
600727 Just {} -> [txt ".."]
601728 Nothing -> []
602− inci . braces . sitcc $ sep (comma >> breakpoint) sitcc (fields <> dotdot)
729+ inci . braces N $
730+ sep commaDel sitcc (fields <> dotdot)
603731 RecordUpd {..} -> do
604732 located rupd_expr p_hsExpr
605− breakpoint
606− inci . braces . sitcc $
607− sep (comma >> breakpoint) (sitcc . located' p_hsRecField) rupd_flds
608− ExprWithTySig affix x -> sitcc $ do
733+ useRecordDot' <- useRecordDot
734+ let mrs sp = case getLoc sp of
735+ RealSrcSpan r -> Just r
736+ _ -> Nothing
737+ let isPluginForm =
738+ ((1 +) . srcSpanEndCol <$> mrs rupd_expr)
739+ == (srcSpanStartCol <$> mrs (head rupd_flds))
740+ unless (useRecordDot' && isPluginForm) breakpoint
741+ let updName f =
742+ (f :: HsRecUpdField GhcPs)
743+ { hsRecFieldLbl = case unLoc $ hsRecFieldLbl f of
744+ Ambiguous _ n -> n
745+ Unambiguous _ n -> n
746+ XAmbiguousFieldOcc x -> noExtCon x
747+ }
748+ inci . braces N $
749+ sep
750+ commaDel
751+ (sitcc . located' (p_hsRecField . updName))
752+ rupd_flds
753+ ExprWithTySig NoExtField x HsWC {hswc_body = HsIB {..}} -> sitcc $ do
609754 located x p_hsExpr
755+ space
756+ txt "::"
610757 breakpoint
611− inci $ do
612− txt ":: "
613− let HsWC {..} = affix
614− HsIB {..} = hswc_body
615− located hsib_body p_hsType
616− ArithSeq NoExt _ x -> do
758+ inci $ located hsib_body p_hsType
759+ ExprWithTySig NoExtField _ HsWC {hswc_body = XHsImplicitBndrs x} -> noExtCon x
760+ ExprWithTySig NoExtField _ (XHsWildCardBndrs x) -> noExtCon x
761+ ArithSeq NoExtField _ x ->
617762 case x of
618− From from -> brackets . sitcc $ do
763+ From from -> brackets s $ do
619764 located from p_hsExpr
620765 breakpoint
621766 txt ".."
622− FromThen from next -> brackets . sitcc $ do
623− sitcc $ sep (comma >> breakpoint) (located' p_hsExpr) [from, next]
767+ FromThen from next -> brackets s $ do
768+ sep commaDel (located' p_hsExpr) [from, next]
624769 breakpoint
625770 txt ".."
626− FromTo from to -> brackets . sitcc $ do
771+ FromTo from to -> brackets s $ do
627772 located from p_hsExpr
628773 breakpoint
629− txt ".. "
774+ txt ".."
775+ space
630776 located to p_hsExpr
631− FromThenTo from next to -> brackets . sitcc $ do
632− sitcc $ sep (comma >> breakpoint) (located' p_hsExpr) [from, next]
777+ FromThenTo from next to -> brackets s $ do
778+ sep commaDel (located' p_hsExpr) [from, next]
633779 breakpoint
634− txt ".. "
780+ txt ".."
781+ space
635782 located to p_hsExpr
636− HsSCC NoExt _ name x -> do
783+ HsSCC NoExtField _ name x -> do
637784 txt "{-# SCC "
638785 atom name
639786 txt " #-}"
640787 breakpoint
641788 located x p_hsExpr
642− HsCoreAnn NoExt _ value x -> do
789+ HsCoreAnn NoExtField _ value x -> do
643790 txt "{-# CORE "
644791 atom value
645792 txt " #-}"
646793 breakpoint
647794 located x p_hsExpr
648− HsBracket NoExt x -> p_hsBracket x
795+ HsBracket NoExtField x -> p_hsBracket x
649796 HsRnBracketOut {} -> notImplemented "HsRnBracketOut"
650797 HsTcBracketOut {} -> notImplemented "HsTcBracketOut"
651− HsSpliceE NoExt splice -> p_hsSplice splice
652− HsProc NoExt p e -> do
798+ HsSpliceE NoExtField splice -> p_hsSplice splice
799+ HsProc NoExtField p e -> do
653800 txt "proc"
654801 located p $ \x -> do
655802 breakpoint
@@ -658,92 +805,159 @@ p_hsExpr = \case
658805 txt "->"
659806 placeHanging (cmdTopPlacement (unLoc e)) $
660807 located e p_hsCmdTop
661− HsStatic _ e -> do
808+ HsStatic _ e -> do
662809 txt "static"
663810 breakpoint
664811 inci (located e p_hsExpr)
665− HsArrApp NoExt body input arrType cond ->
666− p_hsCmd (HsCmdArrApp NoExt body input arrType cond)
667− HsArrForm NoExt form mfixity cmds ->
668− p_hsCmd (HsCmdArrForm NoExt form Prefix mfixity cmds)
669812 HsTick {} -> notImplemented "HsTick"
670813 HsBinTick {} -> notImplemented "HsBinTick"
671814 HsTickPragma {} -> notImplemented "HsTickPragma"
672− EWildPat NoExt -> txt "_"
673− EAsPat {} -> notImplemented "EAsPat"
674− EViewPat {} -> notImplemented "EViewPat"
675− ELazyPat {} -> notImplemented "ELazyPat"
676815 HsWrap {} -> notImplemented "HsWrap"
677− XExpr {} -> notImplemented "XExpr"
816+ XExpr x -> noExtCon x
678817
679818p_patSynBind :: PatSynBind GhcPs GhcPs -> R ()
680819p_patSynBind PSB {..} = do
681− txt "pattern "
682− case psb_dir of
683− Unidirectional -> do
684− p_rdrName psb_id
685− inci $ do
686− p_patSynDetails psb_args
687− txt " <-"
688− breakpoint
689− located psb_def p_pat
690− ImplicitBidirectional -> do
820+ let rhs = do
821+ space
822+ case psb_dir of
823+ Unidirectional -> do
824+ txt "<-"
825+ breakpoint
826+ located psb_def p_pat
827+ ImplicitBidirectional -> do
828+ equals
829+ breakpoint
830+ located psb_def p_pat
831+ ExplicitBidirectional mgroup -> do
832+ txt "<-"
833+ breakpoint
834+ located psb_def p_pat
835+ newline
836+ txt "where"
837+ newline
838+ inci (p_matchGroup (Function psb_id) mgroup)
839+ txt "pattern"
840+ case psb_args of
841+ PrefixCon xs -> do
842+ space
691843 p_rdrName psb_id
692844 inci $ do
693− p_patSynDetails psb_args
694− txt " ="
695− breakpoint
696− located psb_def p_pat
697− ExplicitBidirectional mgroup -> do
845+ switchLayout (getLoc <$> xs) $ do
846+ unless (null xs) breakpoint
847+ sitcc (sep breakpoint p_rdrName xs)
848+ rhs
849+ RecCon xs -> do
850+ space
698851 p_rdrName psb_id
699852 inci $ do
700− p_patSynDetails psb_args
701− txt " <-"
853+ switchLayout (getLoc . recordPatSynPatVar <$> xs) $ do
854+ unless (null xs) breakpoint
855+ braces N $
856+ sep commaDel (p_rdrName . recordPatSynPatVar) xs
857+ rhs
858+ InfixCon l r -> do
859+ switchLayout [getLoc l, getLoc r] $ do
860+ space
861+ p_rdrName l
702862 breakpoint
703− located psb_def p_pat
704− newline
705− line (txt "where")
706− inci (p_matchGroup (Function psb_id) mgroup)
707−p_patSynBind (XPatSynBind NoExt) = notImplemented "XPatSynBind"
708−
709−p_patSynDetails :: HsPatSynDetails (Located RdrName) -> R ()
710−p_patSynDetails = \case
711− PrefixCon xs ->
712− switchLayout (getLoc <$> xs) $ do
713− unless (null xs) breakpoint
714− sitcc (sep breakpoint p_rdrName xs)
715− RecCon xs ->
716− switchLayout (getLoc . recordPatSynPatVar <$> xs) $ do
717− unless (null xs) breakpoint
718− braces . sitcc $ sep (comma >> breakpoint) (p_rdrName . recordPatSynPatVar) xs
719− InfixCon _ _ -> notImplemented "InfixCon"
863+ inci $ do
864+ p_rdrName psb_id
865+ space
866+ p_rdrName r
867+ inci rhs
868+p_patSynBind (XPatSynBind x) = noExtCon x
869+
870+p_case ::
871+ Data body =>
872+ -- | Placer
873+ (body -> Placement) ->
874+ -- | Render
875+ (body -> R ()) ->
876+ -- | Expression
877+ LHsExpr GhcPs ->
878+ -- | Match group
879+ MatchGroup GhcPs (Located body) ->
880+ R ()
881+p_case placer render e mgroup = do
882+ txt "case"
883+ space
884+ located e p_hsExpr
885+ space
886+ txt "of"
887+ breakpoint
888+ inci (p_matchGroup' placer render Case mgroup)
889+
890+p_if ::
891+ Data body =>
892+ -- | Placer
893+ (body -> Placement) ->
894+ -- | Render
895+ (body -> R ()) ->
896+ -- | If
897+ LHsExpr GhcPs ->
898+ -- | Then
899+ Located body ->
900+ -- | Else
901+ Located body ->
902+ R ()
903+p_if placer render if' then' else' = do
904+ txt "if"
905+ space
906+ located if' p_hsExpr
907+ breakpoint
908+ inci $ do
909+ txt "then"
910+ space
911+ located then' $ \x ->
912+ placeHanging (placer x) (render x)
913+ breakpoint
914+ txt "else"
915+ space
916+ located else' $ \x ->
917+ placeHanging (placer x) (render x)
918+
919+p_let ::
920+ Data body =>
921+ -- | Render
922+ (body -> R ()) ->
923+ Located (HsLocalBindsLR GhcPs GhcPs) ->
924+ Located body ->
925+ R ()
926+p_let render localBinds e = sitcc $ do
927+ txt "let"
928+ space
929+ dontUseBraces $ sitcc (located localBinds p_hsLocalBinds)
930+ vlayout space (newline >> txt " ")
931+ txt "in"
932+ space
933+ sitcc (located e render)
720934
721935p_pat :: Pat GhcPs -> R ()
722936p_pat = \case
723− WildPat NoExt -> txt "_"
724− VarPat NoExt name -> p_rdrName name
725− LazyPat NoExt pat -> do
937+ WildPat NoExtField -> txt "_"
938+ VarPat NoExtField name -> p_rdrName name
939+ LazyPat NoExtField pat -> do
726940 txt "~"
727941 located pat p_pat
728− AsPat NoExt name pat -> do
942+ AsPat NoExtField name pat -> do
729943 p_rdrName name
730944 txt "@"
731945 located pat p_pat
732− ParPat NoExt pat ->
733− located pat (parens . p_pat)
734− BangPat NoExt pat -> do
946+ ParPat NoExtField pat ->
947+ located pat (parens S . p_pat)
948+ BangPat NoExtField pat -> do
735949 txt "!"
736950 located pat p_pat
737− ListPat NoExt pats -> do
738− brackets . sitcc $ sep (comma >> breakpoint) (located' p_pat) pats
739− TuplePat NoExt pats boxing -> do
740− let f =
951+ ListPat NoExtField pats ->
952+ brackets S $ sep commaDel (located' p_pat) pats
953+ TuplePat NoExtField pats boxing -> do
954+ let parens' =
741955 case boxing of
742− Boxed -> parens
743− Unboxed -> parensHash
744− f . sitcc $ sep (comma >> breakpoint) (sitcc . located' p_pat) pats
745− SumPat NoExt pat tag arity ->
746− p_unboxedSum tag arity (located pat p_pat)
956+ Boxed -> parens S
957+ Unboxed -> parensHash S
958+ parens' $ sep commaDel (sitcc . located' p_pat) pats
959+ SumPat NoExtField pat tag arity ->
960+ p_unboxedSum S tag arity (located pat p_pat)
747961 ConPatIn pat details ->
748962 case details of
749963 PrefixCon xs -> sitcc $ do
@@ -757,102 +971,115 @@ p_pat = \case
757971 let f = \case
758972 Nothing -> txt ".."
759973 Just x -> located x p_pat_hsRecField
760− inci . braces . sitcc . sep (comma >> breakpoint) f $ case dotdot of
761− Nothing -> Just <$> fields
762− Just n -> (Just <$> take n fields) ++ [Nothing]
763− InfixCon x y -> do
764− located x p_pat
765− space
766− p_rdrName pat
767− breakpoint
768− inci (located y p_pat)
974+ inci . braces N . sep commaDel f $
975+ case dotdot of
976+ Nothing -> Just <$> fields
977+ Just (L _ n) -> (Just <$> take n fields) ++ [Nothing]
978+ InfixCon l r -> do
979+ switchLayout [getLoc l, getLoc r] $ do
980+ located l p_pat
981+ breakpoint
982+ inci $ do
983+ p_rdrName pat
984+ space
985+ located r p_pat
769986 ConPatOut {} -> notImplemented "ConPatOut" -- presumably created by renamer?
770− ViewPat NoExt expr pat -> sitcc $ do
987+ ViewPat NoExtField expr pat -> sitcc $ do
771988 located expr p_hsExpr
772− txt " ->"
989+ space
990+ txt "->"
773991 breakpoint
774992 inci (located pat p_pat)
775− SplicePat NoExt splice -> p_hsSplice splice
776− LitPat NoExt p -> atom p
777− NPat NoExt v _ _ -> located v (atom . ol_val)
778− NPlusKPat NoExt n k _ _ _ -> sitcc $ do
993+ SplicePat NoExtField splice -> p_hsSplice splice
994+ LitPat NoExtField p -> atom p
995+ NPat NoExtField v _ _ -> located v (atom . ol_val)
996+ NPlusKPat NoExtField n k _ _ _ -> sitcc $ do
779997 p_rdrName n
780998 breakpoint
781999 inci $ do
782− txt "+ "
1000+ txt "+"
1001+ space
7831002 located k (atom . ol_val)
784− SigPat hswc pat -> do
1003+ SigPat NoExtField pat hswc -> do
7851004 located pat p_pat
7861005 p_typeAscription hswc
7871006 CoPat {} -> notImplemented "CoPat" -- apparently created at some later stage
788− XPat NoExt -> notImplemented "XPat"
1007+ XPat x -> noExtCon x
7891008
7901009p_pat_hsRecField :: HsRecField' (FieldOcc GhcPs) (LPat GhcPs) -> R ()
7911010p_pat_hsRecField HsRecField {..} = do
7921011 located hsRecFieldLbl $ \x ->
7931012 p_rdrName (rdrNameFieldOcc x)
7941013 unless hsRecPun $ do
795− txt " ="
1014+ space
1015+ equals
7961016 breakpoint
7971017 inci (located hsRecFieldArg p_pat)
7981018
799−p_unboxedSum :: ConTag -> Arity -> R () -> R ()
800−p_unboxedSum tag arity m = do
1019+p_unboxedSum :: BracketStyle -> ConTag -> Arity -> R () -> R ()
1020+p_unboxedSum s tag arity m = do
8011021 let before = tag - 1
8021022 after = arity - before - 1
8031023 args = replicate before Nothing <> [Just m] <> replicate after Nothing
804− f (x,i) = do
805− let isFirst = i == 0
806− isLast = i == arity - 1
1024+ f x =
8071025 case x :: Maybe (R ()) of
8081026 Nothing ->
809− unless (isFirst || isLast) space
1027+ space
8101028 Just m' -> do
811− unless isFirst space
1029+ space
8121030 m'
813− unless isLast space
814− parensHash $ sep (txt "|") f (zip args [0..])
1031+ space
1032+ parensHash s $ sep (txt "|") f args
8151033
8161034p_hsSplice :: HsSplice GhcPs -> R ()
8171035p_hsSplice = \case
818− HsTypedSplice NoExt deco _ expr -> p_hsSpliceTH True expr deco
819− HsUntypedSplice NoExt deco _ expr -> p_hsSpliceTH False expr deco
820− HsQuasiQuote NoExt _ quoterName srcSpan str -> do
1036+ HsTypedSplice NoExtField deco _ expr -> p_hsSpliceTH True expr deco
1037+ HsUntypedSplice NoExtField deco _ expr -> p_hsSpliceTH False expr deco
1038+ HsQuasiQuote NoExtField _ quoterName srcSpan str -> do
8211039 txt "["
8221040 p_rdrName (L srcSpan quoterName)
8231041 txt "|"
824− -- NOTE QuasiQuoters often rely on precise custom strings. We cannot do
825− -- any formatting here without potentially breaking someone's code.
1042+ -- QuasiQuoters often rely on precise custom strings. We cannot do any
1043+ -- formatting here without potentially breaking someone's code.
8261044 atom str
8271045 txt "|]"
8281046 HsSpliced {} -> notImplemented "HsSpliced"
829− XSplice {} -> notImplemented "XSplice"
1047+ HsSplicedT {} -> notImplemented "HsSplicedT"
1048+ XSplice x -> noExtCon x
8301049
831−p_hsSpliceTH
832− :: Bool -- ^ Typed splice?
833− -> LHsExpr GhcPs -- ^ Splice expression
834− -> SpliceDecoration -- ^ Splice decoration
835− -> R ()
1050+p_hsSpliceTH ::
1051+ -- | Typed splice?
1052+ Bool ->
1053+ -- | Splice expression
1054+ LHsExpr GhcPs ->
1055+ -- | Splice decoration
1056+ SpliceDecoration ->
1057+ R ()
8361058p_hsSpliceTH isTyped expr = \case
8371059 HasParens -> do
8381060 txt decoSymbol
839− parens (located expr (sitcc . p_hsExpr))
1061+ parens N (located expr (sitcc . p_hsExpr))
8401062 HasDollar -> do
8411063 txt decoSymbol
8421064 located expr (sitcc . p_hsExpr)
843− NoParens -> do
1065+ NoParens ->
8441066 located expr (sitcc . p_hsExpr)
8451067 where
8461068 decoSymbol = if isTyped then "$$" else "$"
8471069
8481070p_hsBracket :: HsBracket GhcPs -> R ()
8491071p_hsBracket = \case
850− ExpBr NoExt expr -> quote "e" (located expr p_hsExpr)
851− PatBr NoExt pat -> quote "p" (located pat p_pat)
852− DecBrL NoExt decls -> quote "d" (p_hsDecls Free decls)
853− DecBrG NoExt _ -> notImplemented "DecBrG" -- result of renamer
854− TypBr NoExt ty -> quote "t" (located ty p_hsType)
855− VarBr NoExt isSingleQuote name -> do
1072+ ExpBr NoExtField expr -> do
1073+ anns <- getEnclosingAnns
1074+ let name = case anns of
1075+ AnnOpenEQ : _ -> ""
1076+ _ -> "e"
1077+ quote name (located expr p_hsExpr)
1078+ PatBr NoExtField pat -> located pat (quote "p" . p_pat)
1079+ DecBrL NoExtField decls -> quote "d" (p_hsDecls Free decls)
1080+ DecBrG NoExtField _ -> notImplemented "DecBrG" -- result of renamer
1081+ TypBr NoExtField ty -> quote "t" (located ty p_hsType)
1082+ VarBr NoExtField isSingleQuote name -> do
8561083 txt (bool "''" "'" isSingleQuote)
8571084 -- HACK As you can see we use 'noLoc' here to be able to pass name into
8581085 -- 'p_rdrName' since the latter expects a "located" thing. The problem
@@ -860,19 +1087,20 @@ p_hsBracket = \case
8601087 -- turn makes it impossible to detect if there are parentheses around
8611088 -- it, etc. So we have to add parentheses manually assuming they are
8621089 -- necessary for all operators.
863− let isOperator = all
864− (\i -> isPunctuation i || isSymbol i)
865− (showOutputable (rdrNameOcc name))
866− && not (doesNotNeedExtraParens name)
867− wrapper = if isOperator then parens else id
1090+ let isOperator =
1091+ all
1092+ (\i -> isPunctuation i || isSymbol i)
1093+ (showOutputable (rdrNameOcc name))
1094+ && not (doesNotNeedExtraParens name)
1095+ wrapper = if isOperator then parens N else id
8681096 wrapper $ p_rdrName (noLoc name)
869− TExpBr NoExt expr -> do
1097+ TExpBr NoExtField expr -> do
8701098 txt "[||"
8711099 breakpoint'
8721100 located expr p_hsExpr
8731101 breakpoint'
8741102 txt "||]"
875− XBracket {} -> notImplemented "XBracket"
1103+ XBracket x -> noExtCon x
8761104 where
8771105 quote :: Text -> R () -> R ()
8781106 quote name body = do
@@ -885,12 +1113,65 @@ p_hsBracket = \case
8851113 breakpoint'
8861114 txt "|]"
8871115
1116+-- Print the source text of a string literal while indenting
1117+-- gaps correctly.
1118+
1119+p_stringLit :: String -> R ()
1120+p_stringLit src =
1121+ let s = splitGaps src
1122+ singleLine =
1123+ txt $ Text.pack (mconcat s)
1124+ multiLine =
1125+ sitcc $ sep breakpoint (txt . Text.pack) (backslashes s)
1126+ in vlayout singleLine multiLine
1127+ where
1128+ -- Split a string on gaps (backslash delimited whitespaces)
1129+ --
1130+ -- > splitGaps "bar\\ \\fo\\&o" == ["bar", "fo\\&o"]
1131+ splitGaps :: String -> [String]
1132+ splitGaps "" = []
1133+ splitGaps s =
1134+ let -- A backslash and a whitespace starts a "gap"
1135+ p (Just '\\', _, _) = True
1136+ p (_, '\\', Just c) | ghcSpace c = False
1137+ p _ = True
1138+ in case span p (zipPrevNext s) of
1139+ (l, r) ->
1140+ let -- drop the initial '\', any amount of 'ghcSpace', and another '\'
1141+ r' = drop 1 . dropWhile ghcSpace . drop 1 $ map orig r
1142+ in map orig l : splitGaps r'
1143+ -- GHC's definition of whitespaces in strings
1144+ -- See: https://gitlab.haskell.org/ghc/ghc/blob/86753475/compiler/parser/Lexer.x#L1653
1145+ ghcSpace :: Char -> Bool
1146+ ghcSpace c = c <= '\x7f' && is_space c
1147+ -- Add backslashes to the inner side of the strings
1148+ --
1149+ -- > backslashes ["a", "b", "c"] == ["a\\", "\\b\\", "\\c"]
1150+ backslashes :: [String] -> [String]
1151+ backslashes (x : y : xs) = (x ++ "\\") : backslashes (('\\' : y) : xs)
1152+ backslashes xs = xs
1153+ -- Attaches previous and next items to each list element
1154+ zipPrevNext :: [a] -> [(Maybe a, a, Maybe a)]
1155+ zipPrevNext xs =
1156+ let z =
1157+ zip
1158+ (zip (Nothing : map Just xs) xs)
1159+ (map Just (tail xs) ++ repeat Nothing)
1160+ in map (\((p, x), n) -> (p, x, n)) z
1161+ orig (_, x, _) = x
1162+
8881163----------------------------------------------------------------------------
8891164-- Helpers
8901165
1166+-- | Return the wrapping function controlling the use of braces according to
1167+-- the current layout.
1168+layoutToBraces :: Layout -> R () -> R ()
1169+layoutToBraces = \case
1170+ SingleLine -> useBraces
1171+ MultiLine -> id
1172+
8911173-- | Append each element in both lists with semigroups. If one list is shorter
8921174-- than the other, return the rest of the longer list unchanged.
893−
8941175liftAppend :: Semigroup a => [a] -> [a] -> [a]
8951176liftAppend [] [] = []
8961177liftAppend [] (y : ys) = y : ys
@@ -898,15 +1179,15 @@ liftAppend (x : xs) [] = x : xs
8981179liftAppend (x : xs) (y : ys) = x <> y : liftAppend xs ys
8991180
9001181getGRHSSpan :: GRHS GhcPs (Located body) -> SrcSpan
901−getGRHSSpan (GRHS NoExt _ body) = getLoc body
902−getGRHSSpan (XGRHS NoExt) = notImplemented "XGRHS"
1182+getGRHSSpan (GRHS NoExtField guards body) =
1183+ combineSrcSpans' $ getLoc body :| map getLoc guards
1184+getGRHSSpan (XGRHS x) = noExtCon x
9031185
9041186-- | Place a thing that may have a hanging form. This function handles how
9051187-- to separate it from preceding expressions and whether to bump indentation
9061188-- depending on what sort of expression we have.
907−
9081189placeHanging :: Placement -> R () -> R ()
909−placeHanging placement m = do
1190+placeHanging placement m =
9101191 case placement of
9111192 Hanging -> do
9121193 space
@@ -917,53 +1198,165 @@ placeHanging placement m = do
9171198
9181199-- | Check if given block contains single expression which has a hanging
9191200-- form.
920−
921−blockPlacement
922− :: (body -> Placement)
923− -> [LGRHS GhcPs (Located body)]
924− -> Placement
925−blockPlacement placer [(L _ (GRHS NoExt _ (L _ x)))] = placer x
1201+blockPlacement ::
1202+ (body -> Placement) ->
1203+ [LGRHS GhcPs (Located body)] ->
1204+ Placement
1205+blockPlacement placer [L _ (GRHS NoExtField _ (L _ x))] = placer x
9261206blockPlacement _ _ = Normal
9271207
9281208-- | Check if given command has a hanging form.
929−
9301209cmdPlacement :: HsCmd GhcPs -> Placement
9311210cmdPlacement = \case
932− HsCmdLam NoExt _ -> Hanging
933− HsCmdCase NoExt _ _ -> Hanging
934− HsCmdDo NoExt _ -> Hanging
1211+ HsCmdLam NoExtField _ -> Hanging
1212+ HsCmdCase NoExtField _ _ -> Hanging
1213+ HsCmdDo NoExtField _ -> Hanging
9351214 _ -> Normal
9361215
9371216cmdTopPlacement :: HsCmdTop GhcPs -> Placement
9381217cmdTopPlacement = \case
939− HsCmdTop NoExt (L _ x) -> cmdPlacement x
940− XCmdTop {} -> notImplemented "XCmdTop"
1218+ HsCmdTop NoExtField (L _ x) -> cmdPlacement x
1219+ XCmdTop x -> noExtCon x
9411220
9421221-- | Check if given expression has a hanging form.
943−
9441222exprPlacement :: HsExpr GhcPs -> Placement
9451223exprPlacement = \case
946− HsLam NoExt _ -> Hanging
947− HsLamCase NoExt _ -> Hanging
948− HsCase NoExt _ _ -> Hanging
949− HsDo NoExt DoExpr _ -> Hanging
950− HsDo NoExt MDoExpr _ -> Hanging
951− RecordCon NoExt _ _ -> Hanging
952− -- If the rightmost expression in an operator chain is hanging, make the
953− -- whole block hanging; so that we can use the common @f = foo $ do@
954− -- style.
955− OpApp NoExt _ _ y -> exprPlacement (unLoc y)
956− HsProc NoExt (L s _) _ ->
1224+ -- Only hang lambdas with single line parameter lists
1225+ HsLam NoExtField mg -> case mg of
1226+ MG _ (L _ [L _ (Match NoExtField _ (x : xs) _)]) _
1227+ | isOneLineSpan (combineSrcSpans' $ fmap getLoc (x :| xs)) ->
1228+ Hanging
1229+ _ -> Normal
1230+ HsLamCase NoExtField _ -> Hanging
1231+ HsCase NoExtField _ _ -> Hanging
1232+ HsDo NoExtField DoExpr _ -> Hanging
1233+ HsDo NoExtField MDoExpr _ -> Hanging
1234+ OpApp NoExtField _ op y ->
1235+ case (fmap getOpNameStr . getOpName . unLoc) op of
1236+ Just "$" -> exprPlacement (unLoc y)
1237+ _ -> Normal
1238+ HsApp NoExtField _ y -> exprPlacement (unLoc y)
1239+ HsProc NoExtField p _ ->
9571240 -- Indentation breaks if pattern is longer than one line and left
9581241 -- hanging. Consequently, only apply hanging when it is safe.
959− if isOneLineSpan s
960− then Hanging
961− else Normal
1242+ if isOneLineSpan (getLoc p)
1243+ then Hanging
1244+ else Normal
9621245 _ -> Normal
9631246
9641247withGuards :: [LGRHS GhcPs (Located body)] -> Bool
9651248withGuards = any (checkOne . unLoc)
9661249 where
9671250 checkOne :: GRHS GhcPs (Located body) -> Bool
968− checkOne (GRHS NoExt [] _) = False
1251+ checkOne (GRHS NoExtField [] _) = False
9691252 checkOne _ = True
1253+
1254+exprOpTree :: LHsExpr GhcPs -> OpTree (LHsExpr GhcPs) (LHsExpr GhcPs)
1255+exprOpTree (L _ (OpApp NoExtField x op y)) = OpBranch (exprOpTree x) op (exprOpTree y)
1256+exprOpTree n = OpNode n
1257+
1258+getOpName :: HsExpr GhcPs -> Maybe RdrName
1259+getOpName = \case
1260+ HsVar NoExtField (L _ a) -> Just a
1261+ _ -> Nothing
1262+
1263+getOpNameStr :: RdrName -> String
1264+getOpNameStr = occNameString . rdrNameOcc
1265+
1266+p_exprOpTree ::
1267+ -- | Bracket style to use
1268+ BracketStyle ->
1269+ OpTree (LHsExpr GhcPs) (LHsExpr GhcPs) ->
1270+ R ()
1271+p_exprOpTree s (OpNode x) = located x (p_hsExpr' s)
1272+p_exprOpTree s (OpBranch x op y) = do
1273+ -- If the beginning of the first argument and the second argument are on
1274+ -- the same line, and the second argument has a hanging form, use hanging
1275+ -- placement.
1276+ let placement =
1277+ if isOneLineSpan
1278+ (mkSrcSpan (srcSpanStart (opTreeLoc x)) (srcSpanStart (opTreeLoc y)))
1279+ then case y of
1280+ OpNode (L _ n) -> exprPlacement n
1281+ _ -> Normal
1282+ else Normal
1283+ -- Distinguish holes used in infix notation.
1284+ -- eg. '1 _foo 2' and '1 `_foo` 2'
1285+ opWrapper = case unLoc op of
1286+ HsUnboundVar NoExtField _ -> backticks
1287+ _ -> id
1288+ layout <- getLayout
1289+ let ub = case layout of
1290+ SingleLine -> useBraces
1291+ MultiLine -> case placement of
1292+ Hanging -> useBraces
1293+ Normal -> dontUseBraces
1294+ opNameStr = (fmap getOpNameStr . getOpName . unLoc) op
1295+ gotDollar = opNameStr == Just "$"
1296+ gotColon = opNameStr == Just ":"
1297+ gotRecordDot = isRecordDot (unLoc op) (opTreeLoc y)
1298+ lhs =
1299+ switchLayout [opTreeLoc x] $
1300+ p_exprOpTree s x
1301+ p_op = located op (opWrapper . p_hsExpr)
1302+ p_y = switchLayout [opTreeLoc y] (p_exprOpTree N y)
1303+ isSection = case (opTreeLoc x, getLoc op) of
1304+ (RealSrcSpan treeSpan, RealSrcSpan opSpan) ->
1305+ srcSpanEndCol treeSpan /= srcSpanStartCol opSpan
1306+ _ -> False
1307+ isDoBlock = \case
1308+ OpNode (L _ HsDo {}) -> True
1309+ _ -> False
1310+ useRecordDot' <- useRecordDot
1311+ if
1312+ | gotColon -> do
1313+ lhs
1314+ space
1315+ p_op
1316+ case placement of
1317+ Hanging -> do
1318+ space
1319+ p_y
1320+ Normal -> do
1321+ breakpoint
1322+ inciIf (isDoBlock y) p_y
1323+ | gotDollar
1324+ && isOneLineSpan (opTreeLoc x)
1325+ && placement == Normal -> do
1326+ useBraces lhs
1327+ space
1328+ p_op
1329+ breakpoint
1330+ inci p_y
1331+ | useRecordDot' && gotRecordDot -> do
1332+ lhs
1333+ when isSection space
1334+ p_op
1335+ p_y
1336+ | otherwise -> do
1337+ ub lhs
1338+ placeHanging placement $ do
1339+ p_op
1340+ space
1341+ p_y
1342+
1343+-- | Return 'True' if given expression is a record-dot operator expression.
1344+isRecordDot ::
1345+ -- | Operator expression
1346+ HsExpr GhcPs ->
1347+ -- | Span of the expression on the right-hand side of the operator
1348+ SrcSpan ->
1349+ Bool
1350+isRecordDot op (RealSrcSpan ySpan) = case op of
1351+ HsVar NoExtField (L (RealSrcSpan opSpan) opName) ->
1352+ (getOpNameStr opName == ".") && (srcSpanEndCol opSpan == srcSpanStartCol ySpan)
1353+ _ -> False
1354+isRecordDot _ _ = False
1355+
1356+-- | Get annotations for the enclosing element.
1357+getEnclosingAnns :: R [AnnKeywordId]
1358+getEnclosingAnns = do
1359+ e <- getEnclosingSpan (const True)
1360+ case e of
1361+ Nothing -> return []
1362+ Just e' -> getAnns (RealSrcSpan e')