@@ -1,35 +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
1316import Bag (bagToList)
1417import BasicTypes
1518import Control.Monad
19+import Ctype (is_space)
1620import Data.Bool (bool)
17−import Data.Char (isPunctuation)
21+import Data.Char (isPunctuation, isSymbol)
1822import Data.Data hiding (Infix, Prefix)
23+import Data.Functor ((<&>))
1924import Data.List (intersperse, sortOn)
25+import Data.List.NonEmpty (NonEmpty (..), (<|))
26+import qualified Data.List.NonEmpty as NE
2027import Data.Text (Text)
28+import qualified Data.Text as Text
2129import GHC
30+import OccName (occNameString)
2231import Ormolu.Printer.Combinators
32+import Ormolu.Printer.Internal
2333import Ormolu.Printer.Meat.Common
34+import {-# SOURCE #-} Ormolu.Printer.Meat.Declaration
2435import Ormolu.Printer.Meat.Declaration.Signature
2536import Ormolu.Printer.Meat.Type
37+import Ormolu.Printer.Operators
2638import Ormolu.Utils
27−import Outputable (Outputable (..))
28−import RdrName (rdrNameOcc)
29−import SrcLoc (combineSrcSpans, isOneLineSpan)
30−import qualified Data.List.NonEmpty as NE
31−import {-# SOURCE #-} Ormolu.Printer.Meat.Declaration
3239
40+-- | Style of a group of equations.
3341data MatchGroupStyle
3442 = Function (Located RdrName)
3543 | PatternBind
@@ -37,87 +45,132 @@ data MatchGroupStyle
3745 | Lambda
3846 | LambdaCase
3947
48+-- | Style of equations in a group.
4049data GroupStyle
4150 = EqualSign
4251 | RightArrow
4352
4453-- | Expression placement. This marks the places where expressions that
4554-- implement handing forms may use them.
46−
4755data Placement
48− = Normal -- ^ Multi-line layout should cause
49− -- insertion of a newline and indentation
50− -- bump
51− | Hanging -- ^ Expressions that have hanging form
52− -- should use it and avoid bumping one level
53− -- 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)
5465
5566p_valDecl :: HsBindLR GhcPs GhcPs -> R ()
56−p_valDecl = line . p_valDecl'
57−
58−p_valDecl' :: HsBindLR GhcPs GhcPs -> R ()
59−p_valDecl' = \case
60− FunBind NoExt funId funMatches _ _ -> p_funBind funId funMatches
61− PatBind NoExt pat grhss _ -> p_match PatternBind False NoSrcStrict [pat] grhss
67+p_valDecl = \case
68+ FunBind NoExtField funId funMatches _ _ -> p_funBind funId funMatches
69+ PatBind NoExtField pat grhss _ -> p_match PatternBind False NoSrcStrict [pat] grhss
6270 VarBind {} -> notImplemented "VarBinds" -- introduced by the type checker
6371 AbsBinds {} -> notImplemented "AbsBinds" -- introduced by the type checker
64− PatSynBind NoExt psb -> p_patSynBind psb
65− XHsBindsLR NoExt -> notImplemented "XHsBindsLR"
66−
67−p_funBind
68− :: Located RdrName
69− -> MatchGroup GhcPs (LHsExpr GhcPs)
70− -> R ()
71−p_funBind name mgroup =
72− p_matchGroup (Function name) mgroup
73−
74−p_matchGroup
75− :: MatchGroupStyle
76− -> MatchGroup GhcPs (LHsExpr GhcPs)
77− -> R ()
72+ PatSynBind NoExtField psb -> p_patSynBind psb
73+ XHsBindsLR x -> noExtCon x
74+
75+p_funBind ::
76+ Located RdrName ->
77+ MatchGroup GhcPs (LHsExpr GhcPs) ->
78+ R ()
79+p_funBind name = p_matchGroup (Function name)
80+
81+p_matchGroup ::
82+ MatchGroupStyle ->
83+ MatchGroup GhcPs (LHsExpr GhcPs) ->
84+ R ()
7885p_matchGroup = p_matchGroup' exprPlacement p_hsExpr
7986
80−p_matchGroup'
81− :: Data body
82− => (body -> Placement)
83− -> (body -> R ())
84− -> MatchGroupStyle
85− -> MatchGroup GhcPs (Located body)
86− -> R ()
87−p_matchGroup' placer pretty style MG {..} =
88− sep newline (located' (\m@Match {..} ->
89− p_match' placer pretty style (isInfixMatch m) (matchStrictness m) m_pats m_grhss))
90− (unLoc mg_alts)
91−p_matchGroup' _ _ _ (XMatchGroup NoExt) = notImplemented "XMatchGroup"
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
99+ let ob = case style of
100+ Case -> id
101+ LambdaCase -> id
102+ _ -> dontUseBraces
103+ -- Since we are forcing braces on 'sepSemi' based on 'ob', we have to
104+ -- restore the brace state inside the sepsemi.
105+ ub <- bool dontUseBraces useBraces <$> canUseBraces
106+ ob $ sepSemi (located' (ub . p_Match)) (unLoc mg_alts)
107+ where
108+ p_Match m@Match {..} =
109+ p_match'
110+ placer
111+ render
112+ (adjustMatchGroupStyle m style)
113+ (isInfixMatch m)
114+ (matchStrictness m)
115+ m_pats
116+ m_grhss
117+ p_Match (XMatch x) = noExtCon x
118+p_matchGroup' _ _ _ (XMatchGroup x) = noExtCon x
119+
120+-- | Function id obtained through pattern matching on 'FunBind' should not
121+-- be used to print the actual equations because the different ‘RdrNames’
122+-- used in the equations may have different “decorations” (such as backticks
123+-- and paretheses) associated with them. It is necessary to use per-equation
124+-- names obtained from 'm_ctxt' of 'Match'. This function replaces function
125+-- name inside of 'Function' accordingly.
126+adjustMatchGroupStyle ::
127+ Match GhcPs body ->
128+ MatchGroupStyle ->
129+ MatchGroupStyle
130+adjustMatchGroupStyle m = \case
131+ Function _ -> (Function . mc_fun . m_ctxt) m
132+ style -> style
92133
93134matchStrictness :: Match id body -> SrcStrictness
94135matchStrictness match =
95136 case m_ctxt match of
96− FunRhs{mc_strictness=s} -> s
137+ FunRhs {mc_strictness = s} -> s
97138 _ -> NoSrcStrict
98139
99−p_match
100− :: MatchGroupStyle
101− -> Bool -- ^ Is this an infix match?
102− -> SrcStrictness -- ^ Strictness prefix (FunBind)
103− -> [LPat GhcPs]
104− -> GRHSs GhcPs (LHsExpr GhcPs)
105− -> 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 ()
106152p_match = p_match' exprPlacement p_hsExpr
107153
108−p_match'
109− :: Data body
110− => (body -> Placement)
111− -> (body -> R ())
112− -> MatchGroupStyle
113− -> Bool -- ^ Is this an infix match?
114− -> SrcStrictness -- ^ Strictness prefix (FunBind)
115− -> [LPat GhcPs]
116− -> GRHSs GhcPs (Located body)
117− -> R ()
118−p_match' placer pretty style isInfix strictness m_pats m_grhss = do
119− -- NOTE Normally, since patterns may be placed in a multi-line layout, it
120− -- 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
121174 -- indented than function name. This in turn means that indentation for
122175 -- the body should also be bumped. Normally this would mean that bodies
123176 -- would start with two indentation steps applied, which is ugly, so we
@@ -127,23 +180,24 @@ p_match' placer pretty style isInfix strictness m_pats m_grhss = do
127180 NoSrcStrict -> return ()
128181 SrcStrict -> txt "!"
129182 SrcLazy -> txt "~"
130− inci' <- case NE.nonEmpty m_pats of
131− Nothing -> id <$ case style of
132− Function name -> p_rdrName name
133− _ -> return ()
183+ indentBody <- case NE.nonEmpty m_pats of
184+ Nothing ->
185+ False <$ case style of
186+ Function name -> p_rdrName name
187+ _ -> return ()
134188 Just ne_pats -> do
135− let combinedSpans = combineSrcSpans' $
136− getLoc <$> ne_pats
137− inci' = if isOneLineSpan combinedSpans
138− then id
139− else inci
189+ let combinedSpans = case style of
190+ Function name -> combineSrcSpans (getLoc name) patSpans
191+ _ -> patSpans
192+ patSpans = combineSrcSpans' (getLoc <$> ne_pats)
193+ indentBody = not (isOneLineSpan combinedSpans)
140194 switchLayout [combinedSpans] $ do
141195 let stdCase = sep breakpoint (located' p_pat) m_pats
142196 case style of
143197 Function name ->
144198 p_infixDefHelper
145199 isInfix
146− inci'
200+ indentBody
147201 (p_rdrName name)
148202 (located' p_pat <$> m_pats)
149203 PatternBind -> stdCase
@@ -154,225 +208,256 @@ p_match' placer pretty style isInfix strictness m_pats m_grhss = do
154208 BangPat _ _ -> True
155209 SplicePat _ _ -> True
156210 _ -> False
157− txt (if needsSpace then "\\ " else "\\")
158− stdCase
211+ txt "\\"
212+ when needsSpace space
213+ sitcc stdCase
159214 LambdaCase -> stdCase
160− return inci'
161−
162− let
163− -- Calculate position of end of patterns. This is useful when we decide
164− -- about putting certain constructions in hanging positions.
165− endOfPats = case NE.nonEmpty m_pats of
166− Nothing -> case style of
167− Function name -> (Just . srcSpanEnd . getLoc) name
168− _ -> Nothing
169− Just pats -> (Just . srcSpanEnd . getLoc . NE.last) pats
170− isCase = \case
171− Case -> True
172− LambdaCase -> True
173− _ -> False
174− inci' $ do
175− let GRHSs {..} = m_grhss
176− hasGuards = withGuards grhssGRHSs
177− unless (length grhssGRHSs > 1) $ do
178− case style of
179− Function _ | hasGuards -> return ()
180− Function _ -> txt " ="
181− PatternBind -> txt " ="
182− s | isCase s && hasGuards -> return ()
183− _ -> txt " ->"
184− let grhssSpan = combineSrcSpans' $
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
227+ hasGuards = withGuards grhssGRHSs
228+ grhssSpan =
229+ combineSrcSpans' $
185230 getGRHSSpan . unLoc <$> NE.fromList grhssGRHSs
186− patGrhssSpan = maybe grhssSpan
187− (combineSrcSpans grhssSpan . srcLocSpan) endOfPats
188− placement =
189− case endOfPats of
190− Nothing -> blockPlacement placer grhssGRHSs
191− Just spn ->
192− if isOneLineSpan
193− (mkSrcSpan spn (srcSpanStart grhssSpan))
194− then blockPlacement placer grhssGRHSs
195− else Normal
196− inciLocalBinds = case placement of
197− Normal -> id
198− Hanging -> inci
199− p_body = do
200− let groupStyle =
201− if isCase style && hasGuards
231+ patGrhssSpan =
232+ maybe
233+ grhssSpan
234+ (combineSrcSpans grhssSpan . srcLocSpan . srcSpanEnd)
235+ endOfPats
236+ placement =
237+ case endOfPats of
238+ Nothing -> blockPlacement placer grhssGRHSs
239+ Just spn ->
240+ if onTheSameLine spn grhssSpan
241+ then blockPlacement placer grhssGRHSs
242+ else Normal
243+ p_body = do
244+ let groupStyle =
245+ if isCase style && hasGuards
202246 then RightArrow
203247 else EqualSign
204− sep newline (located' (p_grhs' pretty groupStyle)) grhssGRHSs
205− let whereLocation = combineSrcSpans patGrhssSpan $ getLoc grhssLocalBinds
206− whereIsEmpty = GHC.isEmptyLocalBindsPR (unLoc grhssLocalBinds)
207− unless (GHC.eqEmptyLocalBinds (unLoc grhssLocalBinds))
208− . inciLocalBinds
209− . switchLayout [whereLocation] $ do
210− if whereIsEmpty then newline else breakpoint
211− txt "where"
212− unless whereIsEmpty $ do
213− breakpoint
214− inci (located grhssLocalBinds p_hsLocalBinds)
215− case style of
216− Lambda -> placeHanging placement $
217− switchLayout [patGrhssSpan] p_body
218− _ -> switchLayout [patGrhssSpan] $
219− placeHanging placement p_body
248+ sep newline (located' (p_grhs' placer render groupStyle)) grhssGRHSs
249+ p_where = do
250+ let whereIsEmpty = GHC.isEmptyLocalBindsPR (unLoc grhssLocalBinds)
251+ unless (GHC.eqEmptyLocalBinds (unLoc grhssLocalBinds)) $ do
252+ breakpoint
253+ txt "where"
254+ unless whereIsEmpty breakpoint
255+ inci $ located grhssLocalBinds p_hsLocalBinds
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 "->"
264+ switchLayout [patGrhssSpan] $
265+ placeHanging placement p_body
266+ inci p_where
267+p_match' _ _ _ _ _ _ (XGRHSs x) = noExtCon x
220268
221269p_grhs :: GroupStyle -> GRHS GhcPs (LHsExpr GhcPs) -> R ()
222−p_grhs = p_grhs' p_hsExpr
223−
224−p_grhs'
225− :: Data body
226− => (body -> R ())
227− -> GroupStyle
228− -> GRHS GhcPs (Located body)
229− -> R ()
230−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) =
231282 case guards of
232283 [] -> p_body
233284 xs -> do
234− txt "| "
235− sitcc (sep (comma >> breakpoint) (sitcc . located' p_stmt) xs)
285+ txt "|"
236286 space
237− txt $ case style of
238− EqualSign -> "="
239− RightArrow -> "->"
240− breakpoint
241− 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
242293 where
243− p_body = located body pretty
244−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
245307
246308p_hsCmd :: HsCmd GhcPs -> R ()
247309p_hsCmd = \case
248− HsCmdArrApp NoExt body input arrType _ -> do
310+ HsCmdArrApp NoExtField body input arrType _ -> do
249311 located body p_hsExpr
250− txt $ case arrType of
251− HsFirstOrderApp -> " -<"
252− HsHigherOrderApp -> " -<<"
253− placeHanging (exprPlacement (unLoc input)) $
254− located input p_hsExpr
255− 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
256320 located form p_hsExpr
257− unless (null cmds) $ do
321+ unless (null cmds) $ do
258322 breakpoint
259323 inci (sequence_ (intersperse breakpoint (located' p_hsCmdTop <$> cmds)))
260− HsCmdArrForm NoExt form Infix _ [left, right] -> do
324+ HsCmdArrForm NoExtField form Infix _ [left, right] -> do
261325 located left p_hsCmdTop
262326 space
263327 located form p_hsExpr
264328 placeHanging (cmdTopPlacement (unLoc right)) $
265329 located right p_hsCmdTop
266− HsCmdArrForm NoExt _ Infix _ _ -> notImplemented "HsCmdArrForm"
330+ HsCmdArrForm NoExtField _ Infix _ _ -> notImplemented "HsCmdArrForm"
267331 HsCmdApp {} ->
268332 -- XXX Does this ever occur in the syntax tree? It does not seem like it
269333 -- does. Open an issue and ping @yumiova if this ever occurs in output.
270334 notImplemented "HsCmdApp"
271− HsCmdLam NoExt mgroup -> p_matchGroup' cmdPlacement p_hsCmd Lambda mgroup
272− HsCmdPar NoExt c -> parens (located c p_hsCmd)
273− HsCmdCase NoExt e mgroup -> do
274− txt "case "
275− located e p_hsExpr
276− txt " of"
277− breakpoint
278− inci (p_matchGroup' cmdPlacement p_hsCmd Case mgroup)
279− HsCmdIf NoExt _ if' then' else' -> do
280− txt "if "
281− located if' p_hsExpr
282− breakpoint
283− txt "then"
284− located then' $ \x -> do
285− breakpoint
286− inci (p_hsCmd x)
287− breakpoint
288− txt "else"
289− located else' $ \x -> do
290− breakpoint
291− inci (p_hsCmd x)
292− HsCmdLet NoExt localBinds c -> do
293− txt "let "
294− sitcc (located localBinds p_hsLocalBinds)
295− breakpoint
296− txt "in "
297− sitcc (located c p_hsCmd)
298− 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
299344 txt "do"
300345 newline
301− 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))
302348 HsCmdWrap {} -> notImplemented "HsCmdWrap"
303− XCmd {} -> notImplemented "XCmd"
349+ XCmd x -> noExtCon x
304350
305351p_hsCmdTop :: HsCmdTop GhcPs -> R ()
306352p_hsCmdTop = \case
307− HsCmdTop NoExt cmd -> located cmd p_hsCmd
308− 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)
309384
310385p_stmt :: Stmt GhcPs (LHsExpr GhcPs) -> R ()
311−p_stmt = p_stmt' p_hsExpr
312−
313−p_stmt'
314− :: Data body
315− => (body -> R ())
316− -> Stmt GhcPs (Located body)
317− -> R ()
318−p_stmt' pretty = \case
319− LastStmt NoExt body _ _ -> located body pretty
320− BindStmt NoExt l f _ _ -> do
321− 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
322401 space
323402 txt "<-"
324− breakpoint
325− 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)
326413 ApplicativeStmt {} -> notImplemented "ApplicativeStmt" -- generated by renamer
327− BodyStmt NoExt body _ _ -> located body pretty
328− LetStmt NoExt binds -> do
329− txt "let "
414+ BodyStmt NoExtField body _ _ -> located body render
415+ LetStmt NoExtField binds -> do
416+ txt "let"
417+ space
330418 sitcc $ located binds p_hsLocalBinds
331419 ParStmt {} ->
332− -- NOTE 'ParStmt' should always be eliminated in 'gatherStmt' already,
333− -- such that it never occurs in 'p_stmt''. Consequently, handling it
334− -- 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.
335423 notImplemented "ParStmt"
336− TransStmt {..} -> do
337− -- NOTE 'TransStmt' only needs to account for pretty printing itself,
338− -- since pretty printing of relevant statements (e.g., in 'trS_stmts')
339− -- 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'.
340428 case (trS_form, trS_by) of
341− (ThenForm, Nothing) -> located trS_using $ \x -> do
429+ (ThenForm, Nothing) -> do
342430 txt "then"
343431 breakpoint
344− inci (p_hsExpr x)
432+ inci $ located trS_using p_hsExpr
345433 (ThenForm, Just e) -> do
346− located trS_using $ \x -> do
347− txt "then"
348− breakpoint
349− inci (p_hsExpr x)
434+ txt "then"
350435 breakpoint
351− located e $ \x -> do
352− txt "by"
353− breakpoint
354− inci (p_hsExpr x)
355− (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
356442 txt "then group using"
357443 breakpoint
358− inci (p_hsExpr x)
444+ inci $ located trS_using p_hsExpr
359445 (GroupForm, Just e) -> do
360− located e $ \x -> do
361− txt "then group by"
362− breakpoint
363− inci (p_hsExpr x)
446+ txt "then group by"
364447 breakpoint
365− located trS_using $ \x -> do
366− txt "using"
367− breakpoint
368− inci (p_hsExpr x)
448+ inci $ located e p_hsExpr
449+ breakpoint
450+ txt "using"
451+ breakpoint
452+ inci $ located trS_using p_hsExpr
369453 RecStmt {..} -> do
370− txt "rec "
371− sitcc $ sep newline (located' (p_stmt' pretty)) recS_stmts
372− XStmtLR {} -> notImplemented "XStmtLR"
454+ txt "rec"
455+ space
456+ sitcc $ sepSemi (withSpacing (p_stmt' placer render)) recS_stmts
457+ XStmtLR c -> noExtCon c
373458
374459gatherStmt :: ExprLStmt GhcPs -> [[ExprLStmt GhcPs]]
375−gatherStmt (L _ (ParStmt NoExt block _ _)) =
460+gatherStmt (L _ (ParStmt NoExtField block _ _)) =
376461 foldr ((<>) . gatherStmtBlock) [] block
377462gatherStmt (L s stmt@TransStmt {..}) =
378463 foldr liftAppend [] ((gatherStmt <$> trS_stmts) <> pure [[L s stmt]])
@@ -381,338 +466,498 @@ gatherStmt stmt = [[stmt]]
381466gatherStmtBlock :: ParStmtBlock GhcPs GhcPs -> [[ExprLStmt GhcPs]]
382467gatherStmtBlock (ParStmtBlock _ stmts _ _) =
383468 foldr (liftAppend . gatherStmt) [] stmts
384−gatherStmtBlock XParStmtBlock {} = notImplemented "XParStmtBlock"
469+gatherStmtBlock (XParStmtBlock x) = noExtCon x
385470
386471p_hsLocalBinds :: HsLocalBindsLR GhcPs GhcPs -> R ()
387472p_hsLocalBinds = \case
388− HsValBinds NoExt (ValBinds NoExt bag lsigs) -> do
389− let ssStart = either
390− (srcSpanStart . getLoc)
391− (srcSpanStart . getLoc)
392− items =
393− (Left <$> bagToList bag) ++ (Right <$> lsigs)
394− p_item (Left x) = located x p_valDecl'
395− p_item (Right x) = located x p_sigDecl'
396− sitcc $ sep newline (sitcc . p_item) (sortOn ssStart items)
397− HsValBinds NoExt _ -> notImplemented "HsValBinds"
398− HsIPBinds NoExt _ -> notImplemented "HsIPBinds"
399− EmptyLocalBinds NoExt -> return ()
400− XHsLocalBindsLR _ -> notImplemented "XHsLocalBindsLR"
401−
402−p_hsRecField
403− :: (Data id, Outputable id)
404− => HsRecField' id (LHsExpr GhcPs)
405− -> R ()
406−p_hsRecField = \HsRecField {..} -> do
407− located hsRecFieldLbl atom
408− unless hsRecPun $ do
409− txt " = "
410− located hsRecFieldArg p_hsExpr
411−
412−p_hsTupArg :: HsTupArg GhcPs -> R ()
413−p_hsTupArg = \case
414− Present NoExt x -> located x p_hsExpr
415− Missing NoExt -> pure ()
416− XTupArg {} -> notImplemented "XTupArg"
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) ->
494+ -- Second argument of IPBind is always Left before type-checking.
495+ let p_ipBind (IPBind NoExtField (Left name) expr) = do
496+ atom name
497+ space
498+ equals
499+ breakpoint
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
505+ in sepSemi (located' p_ipBind) xs
506+ HsIPBinds NoExtField _ -> notImplemented "HsIpBinds"
507+ EmptyLocalBinds NoExtField -> return ()
508+ XHsLocalBindsLR x -> noExtCon x
509+
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)
417523
418524p_hsExpr :: HsExpr GhcPs -> R ()
419−p_hsExpr = \case
420− HsVar NoExt name -> p_rdrName name
421− HsUnboundVar NoExt _ -> notImplemented "HsUnboundVar"
422− HsConLikeOut NoExt _ -> notImplemented "HsConLikeOut"
423− 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 ->
424533 case x of
425− Unambiguous NoExt name -> p_rdrName name
426− Ambiguous NoExt name -> p_rdrName name
427− XAmbiguousFieldOcc NoExt -> notImplemented "XAmbiguousFieldOcc"
428− 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
429538 txt "#"
430539 atom v
431− HsIPVar NoExt (HsIPName name) -> do
540+ HsIPVar NoExtField (HsIPName name) -> do
432541 txt "?"
433542 atom name
434− HsOverLit NoExt v -> atom (ol_val v)
435− HsLit NoExt lit -> atom lit
436− 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 ->
437550 p_matchGroup Lambda mgroup
438− HsLamCase NoExt mgroup -> do
551+ HsLamCase NoExtField mgroup -> do
439552 txt "\\case"
440− newline
441− inci (p_matchGroup LambdaCase mgroup)
442− HsApp NoExt f x -> sitcc $ do
443− located f p_hsExpr
444553 breakpoint
445− inci (located x p_hsExpr)
446− HsAppType a e -> do
554+ inci (p_matchGroup LambdaCase mgroup)
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
447612 located e p_hsExpr
448613 breakpoint
449614 inci $ do
450615 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 ()
451621 located (hswc_body a) p_hsType
452− OpApp NoExt x op y -> do
453− located x p_hsExpr
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 "-"
454627 space
455− let opWrapper = case unLoc op of
456− EWildPat NoExt -> backticks
457− _ -> id
458− located op (opWrapper . p_hsExpr)
459− placeHanging (exprPlacement (unLoc y)) $
460− located y p_hsExpr
461− NegApp NoExt e _ -> do
462− txt "- "
463628 located e p_hsExpr
464− HsPar NoExt e -> parens (located e p_hsExpr)
465− SectionL NoExt x op -> do
629+ HsPar NoExtField e ->
630+ parens s (located e (dontUseBraces . p_hsExpr))
631+ SectionL NoExtField x op -> do
466632 located x p_hsExpr
467633 breakpoint
468634 inci (located op p_hsExpr)
469− SectionR NoExt op x -> do
635+ SectionR NoExtField op x -> do
470636 located op p_hsExpr
471− breakpoint
637+ useRecordDot' <- useRecordDot
638+ let isRecordDot' = isRecordDot (unLoc op) (getLoc x)
639+ unless (useRecordDot' && isRecordDot') breakpoint
472640 inci (located x p_hsExpr)
473− ExplicitTuple NoExt args boxity -> do
641+ ExplicitTuple NoExtField args boxity ->
474642 let isSection = any (isMissing . unLoc) args
475643 isMissing = \case
476− Missing NoExt -> True
644+ Missing NoExtField -> True
477645 _ -> False
478− 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' =
479652 case boxity of
480653 Boxed -> parens
481654 Unboxed -> parensHash
482− if isSection
483− then switchLayout [] . parens' $
484− sep comma (located' p_hsTupArg) args
485− else switchLayout (getLoc <$> args) . parens' . sitcc $
486− sep (comma >> breakpoint) (sitcc . located' p_hsTupArg) args
487− ExplicitSum NoExt tag arity e -> do
488− let before = tag - 1
489− after = arity - before - 1
490− args = replicate before Nothing <> [Just e] <> replicate after Nothing
491− f (x,i) = do
492− let isFirst = i == 0
493− isLast = i == arity - 1
494− case x of
495− Nothing ->
496− unless (isFirst || isLast) space
497− Just l -> do
498− unless isFirst space
499− located l p_hsExpr
500− unless isLast space
501− parensHash $ sep (txt "|") f (zip args [0..])
502− HsCase NoExt e mgroup -> do
503− txt "case "
504− located e p_hsExpr
505− txt " of"
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
669+ txt "if"
506670 breakpoint
507− inci (p_matchGroup Case mgroup)
508− HsIf NoExt _ if' then' else' -> do
509− txt "if "
510− located if' p_hsExpr
511− breakpoint
512− txt "then"
513− located then' $ \x -> do
514− breakpoint
515− inci (p_hsExpr x)
516− breakpoint
517− txt "else"
518− located else' $ \x -> do
519− breakpoint
520− inci (p_hsExpr x)
521− HsMultiIf NoExt guards -> do
522− txt "if "
523− sitcc $ sep newline (located' (p_grhs RightArrow)) guards
524− HsLet NoExt localBinds e -> do
525− txt "let "
526− sitcc (located localBinds p_hsLocalBinds)
527− vlayout space (newline >> space)
528− txt "in "
529− sitcc (located e p_hsExpr)
530− 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
531675 let doBody header = do
532676 txt header
533− newline
534− inci $ located es (sep newline (located' (sitcc . p_stmt)))
535− compBody = brackets $ located es $ \xs -> do
536− let p_parBody = sitcc . sep
537− (breakpoint >> txt "| ")
538− p_seqBody
539− p_seqBody = sitcc . sep
540− (comma >> breakpoint)
541− (located' (sitcc . p_stmt))
677+ breakpoint
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))
542693 stmts = init xs
543694 yield = last xs
544695 lists = foldr (liftAppend . gatherStmt) [] stmts
545696 located yield p_stmt
546697 breakpoint
547− txt "| "
698+ txt "|"
699+ space
548700 p_parBody lists
549701 case ctx of
550702 DoExpr -> doBody "do"
551703 MDoExpr -> doBody "mdo"
552704 ListComp -> compBody
553705 MonadComp -> notImplemented "MonadComp"
554− ArrowExpr -> notImplemented "ArrowExpr"
706+ ArrowExpr -> notImplemented "ArrowExpr"
555707 GhciStmtCtxt -> notImplemented "GhciStmtCtxt"
556708 PatGuard _ -> notImplemented "PatGuard"
557709 ParStmtCtxt _ -> notImplemented "ParStmtCtxt"
558710 TransStmtCtxt _ -> notImplemented "TransStmtCtxt"
559711 ExplicitList _ _ xs ->
560− brackets . sitcc $ sep (comma >> breakpoint) (sitcc . located' p_hsExpr) xs
712+ brackets s $
713+ sep commaDel (sitcc . located' p_hsExpr) xs
561714 RecordCon {..} -> do
562715 located rcon_con_name atom
563716 breakpoint
564717 let HsRecFields {..} = rcon_flds
565− 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
566725 dotdot =
567726 case rec_dotdot of
568727 Just {} -> [txt ".."]
569728 Nothing -> []
570− inci . braces . sitcc $ sep (comma >> breakpoint) sitcc (fields <> dotdot)
729+ inci . braces N $
730+ sep commaDel sitcc (fields <> dotdot)
571731 RecordUpd {..} -> do
572732 located rupd_expr p_hsExpr
573− breakpoint
574− inci . braces . sitcc $
575− sep (comma >> breakpoint) (sitcc . located' p_hsRecField) rupd_flds
576− 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
577754 located x p_hsExpr
755+ space
756+ txt "::"
578757 breakpoint
579− inci $ do
580− txt ":: "
581− let HsWC {..} = affix
582− HsIB {..} = hswc_body
583− located hsib_body p_hsType
584− 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 ->
585762 case x of
586− From from -> brackets . sitcc $ do
763+ From from -> brackets s $ do
587764 located from p_hsExpr
588765 breakpoint
589766 txt ".."
590− FromThen from next -> brackets . sitcc $ do
591− sitcc $ sep (comma >> breakpoint) (located' p_hsExpr) [from, next]
767+ FromThen from next -> brackets s $ do
768+ sep commaDel (located' p_hsExpr) [from, next]
592769 breakpoint
593770 txt ".."
594− FromTo from to -> brackets . sitcc $ do
771+ FromTo from to -> brackets s $ do
595772 located from p_hsExpr
596773 breakpoint
597− txt ".. "
774+ txt ".."
775+ space
598776 located to p_hsExpr
599− FromThenTo from next to -> brackets . sitcc $ do
600− 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]
601779 breakpoint
602− txt ".. "
780+ txt ".."
781+ space
603782 located to p_hsExpr
604− HsSCC NoExt _ name x -> do
783+ HsSCC NoExtField _ name x -> do
605784 txt "{-# SCC "
606785 atom name
607786 txt " #-}"
608787 breakpoint
609788 located x p_hsExpr
610− HsCoreAnn NoExt _ value x -> do
789+ HsCoreAnn NoExtField _ value x -> do
611790 txt "{-# CORE "
612791 atom value
613792 txt " #-}"
614793 breakpoint
615794 located x p_hsExpr
616− HsBracket NoExt x -> p_hsBracket x
795+ HsBracket NoExtField x -> p_hsBracket x
617796 HsRnBracketOut {} -> notImplemented "HsRnBracketOut"
618797 HsTcBracketOut {} -> notImplemented "HsTcBracketOut"
619− HsSpliceE NoExt splice -> p_hsSplice splice
620− HsProc NoExt p e -> do
798+ HsSpliceE NoExtField splice -> p_hsSplice splice
799+ HsProc NoExtField p e -> do
621800 txt "proc"
622− located p $ \x -> do
801+ located p $ \x -> do
623802 breakpoint
624803 inci (p_pat x)
625804 breakpoint
626805 txt "->"
627− placeHanging (cmdTopPlacement (unLoc e)) (located e p_hsCmdTop)
628− HsStatic _ e -> do
806+ placeHanging (cmdTopPlacement (unLoc e)) $
807+ located e p_hsCmdTop
808+ HsStatic _ e -> do
629809 txt "static"
630810 breakpoint
631811 inci (located e p_hsExpr)
632− HsArrApp NoExt body input arrType cond ->
633− p_hsCmd (HsCmdArrApp NoExt body input arrType cond)
634− HsArrForm NoExt form mfixity cmds ->
635− p_hsCmd (HsCmdArrForm NoExt form Prefix mfixity cmds)
636812 HsTick {} -> notImplemented "HsTick"
637813 HsBinTick {} -> notImplemented "HsBinTick"
638814 HsTickPragma {} -> notImplemented "HsTickPragma"
639− EWildPat NoExt -> txt "_"
640− EAsPat {} -> notImplemented "EAsPat"
641− EViewPat {} -> notImplemented "EViewPat"
642− ELazyPat {} -> notImplemented "ELazyPat"
643815 HsWrap {} -> notImplemented "HsWrap"
644− XExpr {} -> notImplemented "XExpr"
816+ XExpr x -> noExtCon x
645817
646818p_patSynBind :: PatSynBind GhcPs GhcPs -> R ()
647819p_patSynBind PSB {..} = do
648− txt "pattern "
649− let nonEmptySynDetails = \case
650− PrefixCon (_:_) -> True
651− RecCon (_:_) -> True
652− _ -> False
653− case psb_dir of
654− Unidirectional -> do
655− p_rdrName psb_id
656− when (nonEmptySynDetails psb_args) space
657− p_patSynDetails psb_args
658− txt " <-"
659− breakpoint
660− inci (located psb_def p_pat)
661− 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
662843 p_rdrName psb_id
663− when (nonEmptySynDetails psb_args) space
664− p_patSynDetails psb_args
665− txt " ="
666− breakpoint
667− inci (located psb_def p_pat)
668− ExplicitBidirectional mgroup -> do
844+ inci $ 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
669851 p_rdrName psb_id
670− when (nonEmptySynDetails psb_args) space
671− p_patSynDetails psb_args
672− txt " <-"
673− breakpoint
674− inci (located psb_def p_pat)
675− newline
676852 inci $ do
677− line (txt "where")
678− inci (p_matchGroup (Function psb_id) mgroup)
679−p_patSynBind (XPatSynBind NoExt) = notImplemented "XPatSynBind"
680−
681−p_patSynDetails :: HsPatSynDetails (Located RdrName) -> R ()
682−p_patSynDetails = \case
683− PrefixCon xs ->
684− sitcc $ sep breakpoint p_rdrName xs
685− RecCon xs ->
686− sitcc $ sep breakpoint (p_rdrName . recordPatSynPatVar) xs
687− InfixCon _ _ -> notImplemented "InfixCon"
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
862+ breakpoint
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)
688934
689935p_pat :: Pat GhcPs -> R ()
690936p_pat = \case
691− WildPat NoExt -> txt "_"
692− VarPat NoExt name -> p_rdrName name
693− LazyPat NoExt pat -> do
937+ WildPat NoExtField -> txt "_"
938+ VarPat NoExtField name -> p_rdrName name
939+ LazyPat NoExtField pat -> do
694940 txt "~"
695941 located pat p_pat
696− AsPat NoExt name pat -> do
942+ AsPat NoExtField name pat -> do
697943 p_rdrName name
698944 txt "@"
699945 located pat p_pat
700− ParPat NoExt pat ->
701− located pat (parens . p_pat)
702− BangPat NoExt pat -> do
946+ ParPat NoExtField pat ->
947+ located pat (parens S . p_pat)
948+ BangPat NoExtField pat -> do
703949 txt "!"
704950 located pat p_pat
705− ListPat NoExt pats -> do
706− brackets . sitcc $ sep (comma >> breakpoint) (located' p_pat) pats
707− TuplePat NoExt pats boxing -> do
708− let f =
951+ ListPat NoExtField pats ->
952+ brackets S $ sep commaDel (located' p_pat) pats
953+ TuplePat NoExtField pats boxing -> do
954+ let parens' =
709955 case boxing of
710− Boxed -> parens
711− Unboxed -> parensHash
712− f . sitcc $ sep (comma >> breakpoint) (sitcc . located' p_pat) pats
713− SumPat NoExt pat _ _ -> do
714− -- XXX I'm not sure about this one.
715− 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)
716961 ConPatIn pat details ->
717962 case details of
718963 PrefixCon xs -> sitcc $ do
@@ -726,85 +971,115 @@ p_pat = \case
726971 let f = \case
727972 Nothing -> txt ".."
728973 Just x -> located x p_pat_hsRecField
729− inci . braces . sitcc . sep (comma >> breakpoint) f $ case dotdot of
730− Nothing -> Just <$> fields
731− Just n -> (Just <$> take n fields) ++ [Nothing]
732− InfixCon x y -> do
733− located x p_pat
734− space
735− p_rdrName pat
736− breakpoint
737− 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
738986 ConPatOut {} -> notImplemented "ConPatOut" -- presumably created by renamer?
739− ViewPat NoExt expr pat -> sitcc $ do
987+ ViewPat NoExtField expr pat -> sitcc $ do
740988 located expr p_hsExpr
741− txt " ->"
989+ space
990+ txt "->"
742991 breakpoint
743992 inci (located pat p_pat)
744− SplicePat NoExt splice -> p_hsSplice splice
745− LitPat NoExt p -> atom p
746− NPat NoExt v _ _ -> located v (atom . ol_val)
747− 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
748997 p_rdrName n
749998 breakpoint
750999 inci $ do
751− txt "+ "
1000+ txt "+"
1001+ space
7521002 located k (atom . ol_val)
753− SigPat hswc pat -> do
1003+ SigPat NoExtField pat hswc -> do
7541004 located pat p_pat
7551005 p_typeAscription hswc
7561006 CoPat {} -> notImplemented "CoPat" -- apparently created at some later stage
757− XPat NoExt -> notImplemented "XPat"
1007+ XPat x -> noExtCon x
7581008
7591009p_pat_hsRecField :: HsRecField' (FieldOcc GhcPs) (LPat GhcPs) -> R ()
7601010p_pat_hsRecField HsRecField {..} = do
7611011 located hsRecFieldLbl $ \x ->
7621012 p_rdrName (rdrNameFieldOcc x)
7631013 unless hsRecPun $ do
764− txt " ="
1014+ space
1015+ equals
7651016 breakpoint
7661017 inci (located hsRecFieldArg p_pat)
7671018
1019+p_unboxedSum :: BracketStyle -> ConTag -> Arity -> R () -> R ()
1020+p_unboxedSum s tag arity m = do
1021+ let before = tag - 1
1022+ after = arity - before - 1
1023+ args = replicate before Nothing <> [Just m] <> replicate after Nothing
1024+ f x =
1025+ case x :: Maybe (R ()) of
1026+ Nothing ->
1027+ space
1028+ Just m' -> do
1029+ space
1030+ m'
1031+ space
1032+ parensHash s $ sep (txt "|") f args
1033+
7681034p_hsSplice :: HsSplice GhcPs -> R ()
7691035p_hsSplice = \case
770− HsTypedSplice NoExt deco _ expr -> p_hsSpliceTH True expr deco
771− HsUntypedSplice NoExt deco _ expr -> p_hsSpliceTH False expr deco
772− 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
7731039 txt "["
7741040 p_rdrName (L srcSpan quoterName)
7751041 txt "|"
776− -- NOTE QuasiQuoters often rely on precise custom strings. We cannot do
777− -- 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.
7781044 atom str
7791045 txt "|]"
7801046 HsSpliced {} -> notImplemented "HsSpliced"
781− XSplice {} -> notImplemented "XSplice"
1047+ HsSplicedT {} -> notImplemented "HsSplicedT"
1048+ XSplice x -> noExtCon x
7821049
783−p_hsSpliceTH
784− :: Bool -- ^ Typed splice?
785− -> LHsExpr GhcPs -- ^ Splice expression
786− -> SpliceDecoration -- ^ Splice decoration
787− -> R ()
1050+p_hsSpliceTH ::
1051+ -- | Typed splice?
1052+ Bool ->
1053+ -- | Splice expression
1054+ LHsExpr GhcPs ->
1055+ -- | Splice decoration
1056+ SpliceDecoration ->
1057+ R ()
7881058p_hsSpliceTH isTyped expr = \case
7891059 HasParens -> do
7901060 txt decoSymbol
791− parens (located expr (sitcc . p_hsExpr))
1061+ parens N (located expr (sitcc . p_hsExpr))
7921062 HasDollar -> do
7931063 txt decoSymbol
7941064 located expr (sitcc . p_hsExpr)
795− NoParens -> do
1065+ NoParens ->
7961066 located expr (sitcc . p_hsExpr)
7971067 where
7981068 decoSymbol = if isTyped then "$$" else "$"
7991069
8001070p_hsBracket :: HsBracket GhcPs -> R ()
8011071p_hsBracket = \case
802− ExpBr NoExt expr -> quote "e" (located expr p_hsExpr)
803− PatBr NoExt pat -> quote "p" (located pat p_pat)
804− DecBrL NoExt decls -> quote "d" (p_hsDecls Free decls)
805− DecBrG NoExt _ -> notImplemented "DecBrG" -- result of renamer
806− TypBr NoExt ty -> quote "t" (located ty p_hsType)
807− 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
8081083 txt (bool "''" "'" isSingleQuote)
8091084 -- HACK As you can see we use 'noLoc' here to be able to pass name into
8101085 -- 'p_rdrName' since the latter expects a "located" thing. The problem
@@ -812,17 +1087,20 @@ p_hsBracket = \case
8121087 -- turn makes it impossible to detect if there are parentheses around
8131088 -- it, etc. So we have to add parentheses manually assuming they are
8141089 -- necessary for all operators.
815− let isOperator = any isPunctuation (showOutputable (rdrNameOcc name))
816− && not (doesNotNeedExtraParens name)
817− 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
8181096 wrapper $ p_rdrName (noLoc name)
819− TExpBr NoExt expr -> do
1097+ TExpBr NoExtField expr -> do
8201098 txt "[||"
8211099 breakpoint'
8221100 located expr p_hsExpr
8231101 breakpoint'
8241102 txt "||]"
825− XBracket {} -> notImplemented "XBracket"
1103+ XBracket x -> noExtCon x
8261104 where
8271105 quote :: Text -> R () -> R ()
8281106 quote name body = do
@@ -830,16 +1108,70 @@ p_hsBracket = \case
8301108 txt name
8311109 txt "|"
8321110 breakpoint'
833− body
834− breakpoint'
835− txt "|]"
1111+ inci $ do
1112+ dontUseBraces body
1113+ breakpoint'
1114+ txt "|]"
1115+
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
8361162
8371163----------------------------------------------------------------------------
8381164-- Helpers
8391165
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+
8401173-- | Append each element in both lists with semigroups. If one list is shorter
8411174-- than the other, return the rest of the longer list unchanged.
842−
8431175liftAppend :: Semigroup a => [a] -> [a] -> [a]
8441176liftAppend [] [] = []
8451177liftAppend [] (y : ys) = y : ys
@@ -847,15 +1179,15 @@ liftAppend (x : xs) [] = x : xs
8471179liftAppend (x : xs) (y : ys) = x <> y : liftAppend xs ys
8481180
8491181getGRHSSpan :: GRHS GhcPs (Located body) -> SrcSpan
850−getGRHSSpan (GRHS NoExt _ body) = getLoc body
851−getGRHSSpan (XGRHS NoExt) = notImplemented "XGRHS"
1182+getGRHSSpan (GRHS NoExtField guards body) =
1183+ combineSrcSpans' $ getLoc body :| map getLoc guards
1184+getGRHSSpan (XGRHS x) = noExtCon x
8521185
8531186-- | Place a thing that may have a hanging form. This function handles how
8541187-- to separate it from preceding expressions and whether to bump indentation
8551188-- depending on what sort of expression we have.
856−
8571189placeHanging :: Placement -> R () -> R ()
858−placeHanging placement m = do
1190+placeHanging placement m =
8591191 case placement of
8601192 Hanging -> do
8611193 space
@@ -866,49 +1198,165 @@ placeHanging placement m = do
8661198
8671199-- | Check if given block contains single expression which has a hanging
8681200-- form.
869−
870−blockPlacement
871− :: (body -> Placement)
872− -> [LGRHS GhcPs (Located body)]
873− -> Placement
874−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
8751206blockPlacement _ _ = Normal
8761207
8771208-- | Check if given command has a hanging form.
878−
8791209cmdPlacement :: HsCmd GhcPs -> Placement
8801210cmdPlacement = \case
881− HsCmdLam NoExt _ -> Hanging
882− HsCmdCase NoExt _ _ -> Hanging
883− HsCmdDo NoExt _ -> Hanging
1211+ HsCmdLam NoExtField _ -> Hanging
1212+ HsCmdCase NoExtField _ _ -> Hanging
1213+ HsCmdDo NoExtField _ -> Hanging
8841214 _ -> Normal
8851215
8861216cmdTopPlacement :: HsCmdTop GhcPs -> Placement
8871217cmdTopPlacement = \case
888− HsCmdTop NoExt (L _ x) -> cmdPlacement x
889− XCmdTop {} -> notImplemented "XCmdTop"
1218+ HsCmdTop NoExtField (L _ x) -> cmdPlacement x
1219+ XCmdTop x -> noExtCon x
8901220
8911221-- | Check if given expression has a hanging form.
892−
8931222exprPlacement :: HsExpr GhcPs -> Placement
8941223exprPlacement = \case
895− HsLam NoExt _ -> Hanging
896− HsLamCase NoExt _ -> Hanging
897− HsCase NoExt _ _ -> Hanging
898− HsDo NoExt DoExpr _ -> Hanging
899− HsDo NoExt MDoExpr _ -> Hanging
900− RecordCon NoExt _ _ -> Hanging
901− HsProc NoExt (L s _) _ ->
902− -- Indentation breaks if pattern is longer than one line and left hanging.
903− -- Consequently, only apply hanging when it is safe.
904− if isOneLineSpan s
905− then Hanging
906− else Normal
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 _ ->
1240+ -- Indentation breaks if pattern is longer than one line and left
1241+ -- hanging. Consequently, only apply hanging when it is safe.
1242+ if isOneLineSpan (getLoc p)
1243+ then Hanging
1244+ else Normal
9071245 _ -> Normal
9081246
9091247withGuards :: [LGRHS GhcPs (Located body)] -> Bool
9101248withGuards = any (checkOne . unLoc)
9111249 where
9121250 checkOne :: GRHS GhcPs (Located body) -> Bool
913− checkOne (GRHS NoExt [] _) = False
1251+ checkOne (GRHS NoExtField [] _) = False
9141252 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')