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CodeAction.hs
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-- Copyright (c) 2019 The DAML Authors. All rights reserved.
-- SPDX-License-Identifier: Apache-2.0
{-# LANGUAGE CPP #-}
{-# LANGUAGE DuplicateRecordFields #-}
#include "ghc-api-version.h"
-- | Go to the definition of a variable.
module Development.IDE.Plugin.CodeAction
( descriptor
-- * For testing
, matchRegExMultipleImports
) where
import Bag (isEmptyBag)
import Control.Applicative ((<|>))
import Control.Arrow (second,
(>>>))
import Control.Concurrent.Extra (readVar)
import Control.Monad (guard, join)
import Control.Monad.IO.Class
import Data.Char
import qualified Data.DList as DL
import Data.Function
import Data.Functor
import qualified Data.HashMap.Strict as Map
import qualified Data.HashSet as Set
import Data.List.Extra
import Data.List.NonEmpty (NonEmpty ((:|)))
import qualified Data.List.NonEmpty as NE
import qualified Data.Map as M
import Data.Maybe
import qualified Data.Rope.UTF16 as Rope
import qualified Data.Set as S
import qualified Data.Text as T
import Data.Tuple.Extra (fst3)
import Development.IDE.Core.RuleTypes
import Development.IDE.Core.Rules
import Development.IDE.Core.Service
import Development.IDE.Core.Shake
import Development.IDE.GHC.Compat
import Development.IDE.GHC.Error
import Development.IDE.GHC.ExactPrint
import Development.IDE.GHC.Util (prettyPrint,
printRdrName,
unsafePrintSDoc)
import Development.IDE.Plugin.CodeAction.Args
import Development.IDE.Plugin.CodeAction.ExactPrint
import Development.IDE.Plugin.CodeAction.PositionIndexed
import Development.IDE.Plugin.TypeLenses (GetGlobalBindingTypeSigs (GetGlobalBindingTypeSigs),
suggestSignature)
import Development.IDE.Spans.Common
import Development.IDE.Types.Exports
import Development.IDE.Types.HscEnvEq
import Development.IDE.Types.Location
import Development.IDE.Types.Options
import qualified GHC.LanguageExtensions as Lang
import HscTypes (ImportedModsVal (..),
importedByUser)
import Ide.PluginUtils (subRange)
import Ide.Types
import qualified Language.LSP.Server as LSP
import Language.LSP.Types
import Language.LSP.VFS
import Module (moduleEnvElts)
import OccName
import Outputable (Outputable,
ppr,
showSDoc,
showSDocUnsafe)
import RdrName (GlobalRdrElt (..),
lookupGlobalRdrEnv)
import Safe (atMay)
import SrcLoc (realSrcSpanEnd,
realSrcSpanStart)
import TcRnTypes (ImportAvails (..),
TcGblEnv (..))
import Text.Regex.TDFA (mrAfter,
(=~), (=~~))
descriptor :: PluginId -> PluginDescriptor IdeState
descriptor plId =
(defaultPluginDescriptor plId)
{ pluginRules = mempty,
pluginHandlers = mkPluginHandler STextDocumentCodeAction codeAction
}
-- | Generate code actions.
codeAction
:: IdeState
-> PluginId
-> CodeActionParams
-> LSP.LspM c (Either ResponseError (List (Command |? CodeAction)))
codeAction state _ (CodeActionParams _ _ (TextDocumentIdentifier uri) _range CodeActionContext{_diagnostics=List xs}) = do
contents <- LSP.getVirtualFile $ toNormalizedUri uri
liftIO $ do
let text = Rope.toText . (_text :: VirtualFile -> Rope.Rope) <$> contents
mbFile = toNormalizedFilePath' <$> uriToFilePath uri
diag <- fmap (\(_, _, d) -> d) . filter (\(p, _, _) -> mbFile == Just p) <$> getDiagnostics state
(ideOptions, join -> parsedModule, join -> env, join -> annotatedPS, join -> tcM, join -> har, join -> bindings, join -> gblSigs) <- runAction "CodeAction" state $
(,,,,,,,) <$> getIdeOptions
<*> getParsedModule `traverse` mbFile
<*> use GhcSession `traverse` mbFile
<*> use GetAnnotatedParsedSource `traverse` mbFile
<*> use TypeCheck `traverse` mbFile
<*> use GetHieAst `traverse` mbFile
<*> use GetBindings `traverse` mbFile
<*> use GetGlobalBindingTypeSigs `traverse` mbFile
-- This is quite expensive 0.6-0.7s on GHC
pkgExports <- maybe mempty envPackageExports env
localExports <- readVar (exportsMap $ shakeExtras state)
let
exportsMap = localExports <> pkgExports
df = ms_hspp_opts . pm_mod_summary <$> parsedModule
actions =
[ mkCA title kind isPreferred [x] edit
| x <- xs, (title, kind, isPreferred, tedit) <- suggestAction $ CodeActionArgs exportsMap ideOptions parsedModule text df annotatedPS tcM har bindings gblSigs x
, let edit = WorkspaceEdit (Just $ Map.singleton uri $ List tedit) Nothing
]
actions' = caRemoveRedundantImports parsedModule text diag xs uri
<> actions
<> caRemoveInvalidExports parsedModule text diag xs uri
pure $ Right $ List actions'
mkCA :: T.Text -> Maybe CodeActionKind -> Maybe Bool -> [Diagnostic] -> WorkspaceEdit -> (Command |? CodeAction)
mkCA title kind isPreferred diags edit =
InR $ CodeAction title kind (Just $ List diags) isPreferred Nothing (Just edit) Nothing
suggestAction :: CodeActionArgs -> GhcideCodeActions
suggestAction caa =
concat -- Order these suggestions by priority
[ wrap $ suggestSignature True
, wrap suggestExtendImport
, wrap suggestImportDisambiguation
, wrap suggestNewOrExtendImportForClassMethod
, wrap suggestFillTypeWildcard
, wrap suggestFixConstructorImport
, wrap suggestModuleTypo
, wrap suggestReplaceIdentifier
, wrap removeRedundantConstraints
, wrap suggestAddTypeAnnotationToSatisfyContraints
, wrap suggestConstraint
, wrap suggestImplicitParameter
, wrap suggestHideShadow
, wrap suggestNewDefinition
, wrap suggestNewImport
, wrap suggestDeleteUnusedBinding
, wrap suggestExportUnusedTopBinding
, wrap suggestFillHole -- Lowest priority
]
where
wrap :: ToCodeAction a => a -> GhcideCodeActions
wrap = toCodeAction caa
findSigOfDecl :: (IdP p -> Bool) -> [LHsDecl p] -> Maybe (Sig p)
findSigOfDecl pred decls =
listToMaybe
[ sig
| L _ (SigD _ sig@(TypeSig _ idsSig _)) <- decls,
any (pred . unLoc) idsSig
]
findInstanceHead :: (Outputable (HsType p)) => DynFlags -> String -> [LHsDecl p] -> Maybe (LHsType p)
findInstanceHead df instanceHead decls =
listToMaybe
[ hsib_body
| L _ (InstD _ (ClsInstD _ ClsInstDecl {cid_poly_ty = HsIB {hsib_body}})) <- decls,
showSDoc df (ppr hsib_body) == instanceHead
]
findDeclContainingLoc :: Position -> [Located a] -> Maybe (Located a)
findDeclContainingLoc loc = find (\(L l _) -> loc `isInsideSrcSpan` l)
-- Single:
-- This binding for ‘mod’ shadows the existing binding
-- imported from ‘Prelude’ at haskell-language-server/ghcide/src/Development/IDE/Plugin/CodeAction.hs:10:8-40
-- (and originally defined in ‘GHC.Real’)typecheck(-Wname-shadowing)
-- Multi:
--This binding for ‘pack’ shadows the existing bindings
-- imported from ‘Data.ByteString’ at B.hs:6:1-22
-- imported from ‘Data.ByteString.Lazy’ at B.hs:8:1-27
-- imported from ‘Data.Text’ at B.hs:7:1-16
suggestHideShadow :: ParsedSource -> Maybe TcModuleResult -> Maybe HieAstResult -> Diagnostic -> [(T.Text, [Either TextEdit Rewrite])]
suggestHideShadow ps@(L _ HsModule {hsmodImports}) mTcM mHar Diagnostic {_message, _range}
| Just [identifier, modName, s] <-
matchRegexUnifySpaces
_message
"This binding for ‘([^`]+)’ shadows the existing binding imported from ‘([^`]+)’ at ([^ ]*)" =
suggests identifier modName s
| Just [identifier] <-
matchRegexUnifySpaces
_message
"This binding for ‘([^`]+)’ shadows the existing bindings",
Just matched <- allMatchRegexUnifySpaces _message "imported from ‘([^’]+)’ at ([^ ]*)",
mods <- [(modName, s) | [_, modName, s] <- matched],
result <- nubOrdBy (compare `on` fst) $ mods >>= uncurry (suggests identifier),
hideAll <- ("Hide " <> identifier <> " from all occurence imports", concat $ snd <$> result) =
result <> [hideAll]
| otherwise = []
where
suggests identifier modName s
| Just tcM <- mTcM,
Just har <- mHar,
[s'] <- [x | (x, "") <- readSrcSpan $ T.unpack s],
isUnusedImportedId tcM har (T.unpack identifier) (T.unpack modName) (RealSrcSpan s'),
mDecl <- findImportDeclByModuleName hsmodImports $ T.unpack modName,
title <- "Hide " <> identifier <> " from " <> modName =
if modName == "Prelude" && null mDecl
then maybeToList $ (\(_, te) -> (title, [Left te])) <$> newImportToEdit (hideImplicitPreludeSymbol identifier) ps
else maybeToList $ (title,) . pure . pure . hideSymbol (T.unpack identifier) <$> mDecl
| otherwise = []
findImportDeclByModuleName :: [LImportDecl GhcPs] -> String -> Maybe (LImportDecl GhcPs)
findImportDeclByModuleName decls modName = flip find decls $ \case
(L _ ImportDecl {..}) -> modName == moduleNameString (unLoc ideclName)
_ -> error "impossible"
isTheSameLine :: SrcSpan -> SrcSpan -> Bool
isTheSameLine s1 s2
| Just sl1 <- getStartLine s1,
Just sl2 <- getStartLine s2 =
sl1 == sl2
| otherwise = False
where
getStartLine x = srcLocLine . realSrcSpanStart <$> realSpan x
isUnusedImportedId :: TcModuleResult -> HieAstResult -> String -> String -> SrcSpan -> Bool
isUnusedImportedId
TcModuleResult {tmrTypechecked = TcGblEnv {tcg_imports = ImportAvails {imp_mods}}}
HAR {refMap}
identifier
modName
importSpan
| occ <- mkVarOcc identifier,
impModsVals <- importedByUser . concat $ moduleEnvElts imp_mods,
Just rdrEnv <-
listToMaybe
[ imv_all_exports
| ImportedModsVal {..} <- impModsVals,
imv_name == mkModuleName modName,
isTheSameLine imv_span importSpan
],
[GRE {..}] <- lookupGlobalRdrEnv rdrEnv occ,
importedIdentifier <- Right gre_name,
refs <- M.lookup importedIdentifier refMap =
maybe True (not . any (\(_, IdentifierDetails {..}) -> identInfo == S.singleton Use)) refs
| otherwise = False
suggestRemoveRedundantImport :: ParsedModule -> Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
suggestRemoveRedundantImport ParsedModule{pm_parsed_source = L _ HsModule{hsmodImports}} contents Diagnostic{_range=_range,..}
-- The qualified import of ‘many’ from module ‘Control.Applicative’ is redundant
| Just [_, bindings] <- matchRegexUnifySpaces _message "The( qualified)? import of ‘([^’]*)’ from module [^ ]* is redundant"
, Just (L _ impDecl) <- find (\(L l _) -> srcSpanToRange l == Just _range ) hsmodImports
, Just c <- contents
, ranges <- map (rangesForBindingImport impDecl . T.unpack) (T.splitOn ", " bindings)
, ranges' <- extendAllToIncludeCommaIfPossible False (indexedByPosition $ T.unpack c) (concat ranges)
, not (null ranges')
= [( "Remove " <> bindings <> " from import" , [ TextEdit r "" | r <- ranges' ] )]
-- File.hs:16:1: warning:
-- The import of `Data.List' is redundant
-- except perhaps to import instances from `Data.List'
-- To import instances alone, use: import Data.List()
| _message =~ ("The( qualified)? import of [^ ]* is redundant" :: String)
= [("Remove import", [TextEdit (extendToWholeLineIfPossible contents _range) ""])]
| otherwise = []
caRemoveRedundantImports :: Maybe ParsedModule -> Maybe T.Text -> [Diagnostic] -> [Diagnostic] -> Uri -> [Command |? CodeAction]
caRemoveRedundantImports m contents digs ctxDigs uri
| Just pm <- m,
r <- join $ map (\d -> repeat d `zip` suggestRemoveRedundantImport pm contents d) digs,
allEdits <- [ e | (_, (_, edits)) <- r, e <- edits],
caRemoveAll <- removeAll allEdits,
ctxEdits <- [ x | x@(d, _) <- r, d `elem` ctxDigs],
not $ null ctxEdits,
caRemoveCtx <- map (\(d, (title, tedit)) -> removeSingle title tedit d) ctxEdits
= caRemoveCtx ++ [caRemoveAll]
| otherwise = []
where
removeSingle title tedit diagnostic = mkCA title (Just CodeActionQuickFix) Nothing [diagnostic] WorkspaceEdit{..} where
_changes = Just $ Map.singleton uri $ List tedit
_documentChanges = Nothing
removeAll tedit = InR $ CodeAction{..} where
_changes = Just $ Map.singleton uri $ List tedit
_title = "Remove all redundant imports"
_kind = Just CodeActionQuickFix
_diagnostics = Nothing
_documentChanges = Nothing
_edit = Just WorkspaceEdit{..}
_isPreferred = Nothing
_command = Nothing
_disabled = Nothing
caRemoveInvalidExports :: Maybe ParsedModule -> Maybe T.Text -> [Diagnostic] -> [Diagnostic] -> Uri -> [Command |? CodeAction]
caRemoveInvalidExports m contents digs ctxDigs uri
| Just pm <- m,
Just txt <- contents,
txt' <- indexedByPosition $ T.unpack txt,
r <- mapMaybe (groupDiag pm) digs,
r' <- map (\(t,d,rs) -> (t,d,extend txt' rs)) r,
caRemoveCtx <- mapMaybe removeSingle r',
allRanges <- nubOrd $ [ range | (_,_,ranges) <- r, range <- ranges],
allRanges' <- extend txt' allRanges,
Just caRemoveAll <- removeAll allRanges',
ctxEdits <- [ x | x@(_, d, _) <- r, d `elem` ctxDigs],
not $ null ctxEdits
= caRemoveCtx ++ [caRemoveAll]
| otherwise = []
where
extend txt ranges = extendAllToIncludeCommaIfPossible True txt ranges
groupDiag pm dig
| Just (title, ranges) <- suggestRemoveRedundantExport pm dig
= Just (title, dig, ranges)
| otherwise = Nothing
removeSingle (_, _, []) = Nothing
removeSingle (title, diagnostic, ranges) = Just $ InR $ CodeAction{..} where
tedit = concatMap (\r -> [TextEdit r ""]) $ nubOrd ranges
_changes = Just $ Map.singleton uri $ List tedit
_title = title
_kind = Just CodeActionQuickFix
_diagnostics = Just $ List [diagnostic]
_documentChanges = Nothing
_edit = Just WorkspaceEdit{..}
_command = Nothing
_isPreferred = Nothing
_disabled = Nothing
removeAll [] = Nothing
removeAll ranges = Just $ InR $ CodeAction{..} where
tedit = concatMap (\r -> [TextEdit r ""]) ranges
_changes = Just $ Map.singleton uri $ List tedit
_title = "Remove all redundant exports"
_kind = Just CodeActionQuickFix
_diagnostics = Nothing
_documentChanges = Nothing
_edit = Just WorkspaceEdit{..}
_command = Nothing
_isPreferred = Nothing
_disabled = Nothing
suggestRemoveRedundantExport :: ParsedModule -> Diagnostic -> Maybe (T.Text, [Range])
suggestRemoveRedundantExport ParsedModule{pm_parsed_source = L _ HsModule{..}} Diagnostic{..}
| msg <- unifySpaces _message
, Just export <- hsmodExports
, Just exportRange <- getLocatedRange export
, exports <- unLoc export
, Just (removeFromExport, !ranges) <- fmap (getRanges exports . notInScope) (extractNotInScopeName msg)
<|> (,[_range]) <$> matchExportItem msg
<|> (,[_range]) <$> matchDupExport msg
, subRange _range exportRange
= Just ("Remove ‘" <> removeFromExport <> "’ from export", ranges)
where
matchExportItem msg = regexSingleMatch msg "The export item ‘([^’]+)’"
matchDupExport msg = regexSingleMatch msg "Duplicate ‘([^’]+)’ in export list"
getRanges exports txt = case smallerRangesForBindingExport exports (T.unpack txt) of
[] -> (txt, [_range])
ranges -> (txt, ranges)
suggestRemoveRedundantExport _ _ = Nothing
suggestDeleteUnusedBinding :: ParsedModule -> Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
suggestDeleteUnusedBinding
ParsedModule{pm_parsed_source = L _ HsModule{hsmodDecls}}
contents
Diagnostic{_range=_range,..}
-- Foo.hs:4:1: warning: [-Wunused-binds] Defined but not used: ‘f’
| Just [name] <- matchRegexUnifySpaces _message ".*Defined but not used: ‘([^ ]+)’"
, Just indexedContent <- indexedByPosition . T.unpack <$> contents
= let edits = flip TextEdit "" <$> relatedRanges indexedContent (T.unpack name)
in ([("Delete ‘" <> name <> "’", edits) | not (null edits)])
| otherwise = []
where
relatedRanges indexedContent name =
concatMap (findRelatedSpans indexedContent name) hsmodDecls
toRange = realSrcSpanToRange
extendForSpaces = extendToIncludePreviousNewlineIfPossible
findRelatedSpans :: PositionIndexedString -> String -> Located (HsDecl GhcPs) -> [Range]
findRelatedSpans
indexedContent
name
(L (RealSrcSpan l) (ValD _ (extractNameAndMatchesFromFunBind -> Just (lname, matches)))) =
case lname of
(L nLoc _name) | isTheBinding nLoc ->
let findSig (L (RealSrcSpan l) (SigD _ sig)) = findRelatedSigSpan indexedContent name l sig
findSig _ = []
in
extendForSpaces indexedContent (toRange l) :
concatMap findSig hsmodDecls
_ -> concatMap (findRelatedSpanForMatch indexedContent name) matches
findRelatedSpans _ _ _ = []
extractNameAndMatchesFromFunBind
:: HsBind GhcPs
-> Maybe (Located (IdP GhcPs), [LMatch GhcPs (LHsExpr GhcPs)])
extractNameAndMatchesFromFunBind
FunBind
{ fun_id=lname
, fun_matches=MG {mg_alts=L _ matches}
} = Just (lname, matches)
extractNameAndMatchesFromFunBind _ = Nothing
findRelatedSigSpan :: PositionIndexedString -> String -> RealSrcSpan -> Sig GhcPs -> [Range]
findRelatedSigSpan indexedContent name l sig =
let maybeSpan = findRelatedSigSpan1 name sig
in case maybeSpan of
Just (_span, True) -> pure $ extendForSpaces indexedContent $ toRange l -- a :: Int
Just (RealSrcSpan span, False) -> pure $ toRange span -- a, b :: Int, a is unused
_ -> []
-- Second of the tuple means there is only one match
findRelatedSigSpan1 :: String -> Sig GhcPs -> Maybe (SrcSpan, Bool)
findRelatedSigSpan1 name (TypeSig _ lnames _) =
let maybeIdx = findIndex (\(L _ id) -> isSameName id name) lnames
in case maybeIdx of
Nothing -> Nothing
Just _ | length lnames == 1 -> Just (getLoc $ head lnames, True)
Just idx ->
let targetLname = getLoc $ lnames !! idx
startLoc = srcSpanStart targetLname
endLoc = srcSpanEnd targetLname
startLoc' = if idx == 0
then startLoc
else srcSpanEnd . getLoc $ lnames !! (idx - 1)
endLoc' = if idx == 0 && idx < length lnames - 1
then srcSpanStart . getLoc $ lnames !! (idx + 1)
else endLoc
in Just (mkSrcSpan startLoc' endLoc', False)
findRelatedSigSpan1 _ _ = Nothing
-- for where clause
findRelatedSpanForMatch
:: PositionIndexedString
-> String
-> LMatch GhcPs (LHsExpr GhcPs)
-> [Range]
findRelatedSpanForMatch
indexedContent
name
(L _ Match{m_grhss=GRHSs{grhssLocalBinds}}) = do
case grhssLocalBinds of
(L _ (HsValBinds _ (ValBinds _ bag lsigs))) ->
if isEmptyBag bag
then []
else concatMap (findRelatedSpanForHsBind indexedContent name lsigs) bag
_ -> []
findRelatedSpanForMatch _ _ _ = []
findRelatedSpanForHsBind
:: PositionIndexedString
-> String
-> [LSig GhcPs]
-> LHsBind GhcPs
-> [Range]
findRelatedSpanForHsBind
indexedContent
name
lsigs
(L (RealSrcSpan l) (extractNameAndMatchesFromFunBind -> Just (lname, matches))) =
if isTheBinding (getLoc lname)
then
let findSig (L (RealSrcSpan l) sig) = findRelatedSigSpan indexedContent name l sig
findSig _ = []
in extendForSpaces indexedContent (toRange l) : concatMap findSig lsigs
else concatMap (findRelatedSpanForMatch indexedContent name) matches
findRelatedSpanForHsBind _ _ _ _ = []
isTheBinding :: SrcSpan -> Bool
isTheBinding span = srcSpanToRange span == Just _range
isSameName :: IdP GhcPs -> String -> Bool
isSameName x name = showSDocUnsafe (ppr x) == name
data ExportsAs = ExportName | ExportPattern | ExportAll
deriving (Eq)
getLocatedRange :: Located a -> Maybe Range
getLocatedRange = srcSpanToRange . getLoc
suggestExportUnusedTopBinding :: Maybe T.Text -> ParsedModule -> Diagnostic -> [(T.Text, TextEdit)]
suggestExportUnusedTopBinding srcOpt ParsedModule{pm_parsed_source = L _ HsModule{..}} Diagnostic{..}
-- Foo.hs:4:1: warning: [-Wunused-top-binds] Defined but not used: ‘f’
-- Foo.hs:5:1: warning: [-Wunused-top-binds] Defined but not used: type constructor or class ‘F’
-- Foo.hs:6:1: warning: [-Wunused-top-binds] Defined but not used: data constructor ‘Bar’
| Just source <- srcOpt
, Just [name] <- matchRegexUnifySpaces _message ".*Defined but not used: ‘([^ ]+)’"
<|> matchRegexUnifySpaces _message ".*Defined but not used: type constructor or class ‘([^ ]+)’"
<|> matchRegexUnifySpaces _message ".*Defined but not used: data constructor ‘([^ ]+)’"
, Just (exportType, _) <- find (matchWithDiagnostic _range . snd)
. mapMaybe
(\(L l b) -> if maybe False isTopLevel $ srcSpanToRange l
then exportsAs b else Nothing)
$ hsmodDecls
, Just pos <- fmap _end . getLocatedRange =<< hsmodExports
, Just needComma <- needsComma source <$> hsmodExports
, let exportName = (if needComma then "," else "") <> printExport exportType name
insertPos = pos {_character = pred $ _character pos}
= [("Export ‘" <> name <> "’", TextEdit (Range insertPos insertPos) exportName)]
| otherwise = []
where
-- we get the last export and the closing bracket and check for comma in that range
needsComma :: T.Text -> Located [LIE GhcPs] -> Bool
needsComma _ (L _ []) = False
needsComma source (L (RealSrcSpan l) exports) =
let closeParan = _end $ realSrcSpanToRange l
lastExport = fmap _end . getLocatedRange $ last exports
in case lastExport of
Just lastExport -> not $ T.isInfixOf "," $ textInRange (Range lastExport closeParan) source
_ -> False
needsComma _ _ = False
opLetter :: String
opLetter = ":!#$%&*+./<=>?@\\^|-~"
parenthesizeIfNeeds :: Bool -> T.Text -> T.Text
parenthesizeIfNeeds needsTypeKeyword x
| T.head x `elem` opLetter = (if needsTypeKeyword then "type " else "") <> "(" <> x <>")"
| otherwise = x
matchWithDiagnostic :: Range -> Located (IdP GhcPs) -> Bool
matchWithDiagnostic Range{_start=l,_end=r} x =
let loc = fmap _start . getLocatedRange $ x
in loc >= Just l && loc <= Just r
printExport :: ExportsAs -> T.Text -> T.Text
printExport ExportName x = parenthesizeIfNeeds False x
printExport ExportPattern x = "pattern " <> x
printExport ExportAll x = parenthesizeIfNeeds True x <> "(..)"
isTopLevel :: Range -> Bool
isTopLevel l = (_character . _start) l == 0
exportsAs :: HsDecl p -> Maybe (ExportsAs, Located (IdP p))
exportsAs (ValD _ FunBind {fun_id}) = Just (ExportName, fun_id)
exportsAs (ValD _ (PatSynBind _ PSB {psb_id})) = Just (ExportPattern, psb_id)
exportsAs (TyClD _ SynDecl{tcdLName}) = Just (ExportName, tcdLName)
exportsAs (TyClD _ DataDecl{tcdLName}) = Just (ExportAll, tcdLName)
exportsAs (TyClD _ ClassDecl{tcdLName}) = Just (ExportAll, tcdLName)
exportsAs (TyClD _ FamDecl{tcdFam}) = Just (ExportAll, fdLName tcdFam)
exportsAs _ = Nothing
suggestAddTypeAnnotationToSatisfyContraints :: Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
suggestAddTypeAnnotationToSatisfyContraints sourceOpt Diagnostic{_range=_range,..}
-- File.hs:52:41: warning:
-- * Defaulting the following constraint to type ‘Integer’
-- Num p0 arising from the literal ‘1’
-- * In the expression: 1
-- In an equation for ‘f’: f = 1
-- File.hs:52:41: warning:
-- * Defaulting the following constraints to type ‘[Char]’
-- (Show a0)
-- arising from a use of ‘traceShow’
-- at A.hs:228:7-25
-- (IsString a0)
-- arising from the literal ‘"debug"’
-- at A.hs:228:17-23
-- * In the expression: traceShow "debug" a
-- In an equation for ‘f’: f a = traceShow "debug" a
-- File.hs:52:41: warning:
-- * Defaulting the following constraints to type ‘[Char]’
-- (Show a0)
-- arising from a use of ‘traceShow’
-- at A.hs:255:28-43
-- (IsString a0)
-- arising from the literal ‘"test"’
-- at /Users/serhiip/workspace/ghcide/src/Development/IDE/Plugin/CodeAction.hs:255:38-43
-- * In the fourth argument of ‘seq’, namely ‘(traceShow "test")’
-- In the expression: seq "test" seq "test" (traceShow "test")
-- In an equation for ‘f’:
-- f = seq "test" seq "test" (traceShow "test")
| Just [ty, lit] <- matchRegexUnifySpaces _message (pat False False True False)
<|> matchRegexUnifySpaces _message (pat False False False True)
<|> matchRegexUnifySpaces _message (pat False False False False)
= codeEdit ty lit (makeAnnotatedLit ty lit)
| Just source <- sourceOpt
, Just [ty, lit] <- matchRegexUnifySpaces _message (pat True True False False)
= let lit' = makeAnnotatedLit ty lit;
tir = textInRange _range source
in codeEdit ty lit (T.replace lit lit' tir)
| otherwise = []
where
makeAnnotatedLit ty lit = "(" <> lit <> " :: " <> ty <> ")"
pat multiple at inArg inExpr = T.concat [ ".*Defaulting the following constraint"
, if multiple then "s" else ""
, " to type ‘([^ ]+)’ "
, ".*arising from the literal ‘(.+)’"
, if inArg then ".+In the.+argument" else ""
, if at then ".+at" else ""
, if inExpr then ".+In the expression" else ""
, ".+In the expression"
]
codeEdit ty lit replacement =
let title = "Add type annotation ‘" <> ty <> "’ to ‘" <> lit <> "’"
edits = [TextEdit _range replacement]
in [( title, edits )]
suggestReplaceIdentifier :: Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
suggestReplaceIdentifier contents Diagnostic{_range=_range,..}
-- File.hs:52:41: error:
-- * Variable not in scope:
-- suggestAcion :: Maybe T.Text -> Range -> Range
-- * Perhaps you meant ‘suggestAction’ (line 83)
-- File.hs:94:37: error:
-- Not in scope: ‘T.isPrfixOf’
-- Perhaps you meant one of these:
-- ‘T.isPrefixOf’ (imported from Data.Text),
-- ‘T.isInfixOf’ (imported from Data.Text),
-- ‘T.isSuffixOf’ (imported from Data.Text)
-- Module ‘Data.Text’ does not export ‘isPrfixOf’.
| renameSuggestions@(_:_) <- extractRenamableTerms _message
= [ ("Replace with ‘" <> name <> "’", [mkRenameEdit contents _range name]) | name <- renameSuggestions ]
| otherwise = []
suggestNewDefinition :: IdeOptions -> ParsedModule -> Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
suggestNewDefinition ideOptions parsedModule contents Diagnostic{_message, _range}
-- * Variable not in scope:
-- suggestAcion :: Maybe T.Text -> Range -> Range
| Just [name, typ] <- matchRegexUnifySpaces message "Variable not in scope: ([^ ]+) :: ([^*•]+)"
= newDefinitionAction ideOptions parsedModule _range name typ
| Just [name, typ] <- matchRegexUnifySpaces message "Found hole: _([^ ]+) :: ([^*•]+) Or perhaps"
, [(label, newDefinitionEdits)] <- newDefinitionAction ideOptions parsedModule _range name typ
= [(label, mkRenameEdit contents _range name : newDefinitionEdits)]
| otherwise = []
where
message = unifySpaces _message
newDefinitionAction :: IdeOptions -> ParsedModule -> Range -> T.Text -> T.Text -> [(T.Text, [TextEdit])]
newDefinitionAction IdeOptions{..} parsedModule Range{_start} name typ
| Range _ lastLineP : _ <-
[ realSrcSpanToRange sp
| (L l@(RealSrcSpan sp) _) <- hsmodDecls
, _start `isInsideSrcSpan` l]
, nextLineP <- Position{ _line = _line lastLineP + 1, _character = 0}
= [ ("Define " <> sig
, [TextEdit (Range nextLineP nextLineP) (T.unlines ["", sig, name <> " = error \"not implemented\""])]
)]
| otherwise = []
where
colon = if optNewColonConvention then " : " else " :: "
sig = name <> colon <> T.dropWhileEnd isSpace typ
ParsedModule{pm_parsed_source = L _ HsModule{hsmodDecls}} = parsedModule
suggestFillTypeWildcard :: Diagnostic -> [(T.Text, TextEdit)]
suggestFillTypeWildcard Diagnostic{_range=_range,..}
-- Foo.hs:3:8: error:
-- * Found type wildcard `_' standing for `p -> p1 -> p'
| "Found type wildcard" `T.isInfixOf` _message
, " standing for " `T.isInfixOf` _message
, typeSignature <- extractWildCardTypeSignature _message
= [("Use type signature: ‘" <> typeSignature <> "’", TextEdit _range typeSignature)]
| otherwise = []
suggestModuleTypo :: Diagnostic -> [(T.Text, TextEdit)]
suggestModuleTypo Diagnostic{_range=_range,..}
-- src/Development/IDE/Core/Compile.hs:58:1: error:
-- Could not find module ‘Data.Cha’
-- Perhaps you meant Data.Char (from base-4.12.0.0)
| "Could not find module" `T.isInfixOf` _message
, "Perhaps you meant" `T.isInfixOf` _message = let
findSuggestedModules = map (head . T.words) . drop 2 . T.lines
proposeModule mod = ("replace with " <> mod, TextEdit _range mod)
in map proposeModule $ nubOrd $ findSuggestedModules _message
| otherwise = []
suggestFillHole :: Diagnostic -> [(T.Text, TextEdit)]
suggestFillHole Diagnostic{_range=_range,..}
| Just holeName <- extractHoleName _message
, (holeFits, refFits) <- processHoleSuggestions (T.lines _message)
= map (proposeHoleFit holeName False) holeFits
++ map (proposeHoleFit holeName True) refFits
| otherwise = []
where
extractHoleName = fmap head . flip matchRegexUnifySpaces "Found hole: ([^ ]*)"
proposeHoleFit holeName parenthise name =
( "replace " <> holeName <> " with " <> name
, TextEdit _range $ if parenthise then parens name else name)
parens x = "(" <> x <> ")"
processHoleSuggestions :: [T.Text] -> ([T.Text], [T.Text])
processHoleSuggestions mm = (holeSuggestions, refSuggestions)
{-
• Found hole: _ :: LSP.Handlers
Valid hole fits include def
Valid refinement hole fits include
fromMaybe (_ :: LSP.Handlers) (_ :: Maybe LSP.Handlers)
fromJust (_ :: Maybe LSP.Handlers)
haskell-lsp-types-0.22.0.0:Language.LSP.Types.Window.$sel:_value:ProgressParams (_ :: ProgressParams
LSP.Handlers)
T.foldl (_ :: LSP.Handlers -> Char -> LSP.Handlers)
(_ :: LSP.Handlers)
(_ :: T.Text)
T.foldl' (_ :: LSP.Handlers -> Char -> LSP.Handlers)
(_ :: LSP.Handlers)
(_ :: T.Text)
-}
where
t = id @T.Text
holeSuggestions = do
-- get the text indented under Valid hole fits
validHolesSection <-
getIndentedGroupsBy (=~ t " *Valid (hole fits|substitutions) include") mm
-- the Valid hole fits line can contain a hole fit
holeFitLine <-
mapHead
(mrAfter . (=~ t " *Valid (hole fits|substitutions) include"))
validHolesSection
let holeFit = T.strip $ T.takeWhile (/= ':') holeFitLine
guard (not $ T.null holeFit)
return holeFit
refSuggestions = do -- @[]
-- get the text indented under Valid refinement hole fits
refinementSection <-
getIndentedGroupsBy (=~ t " *Valid refinement hole fits include") mm
-- get the text for each hole fit
holeFitLines <- getIndentedGroups (tail refinementSection)
let holeFit = T.strip $ T.unwords holeFitLines
guard $ not $ holeFit =~ t "Some refinement hole fits suppressed"
return holeFit
mapHead f (a:aa) = f a : aa
mapHead _ [] = []
-- > getIndentedGroups [" H1", " l1", " l2", " H2", " l3"] = [[" H1,", " l1", " l2"], [" H2", " l3"]]
getIndentedGroups :: [T.Text] -> [[T.Text]]
getIndentedGroups [] = []
getIndentedGroups ll@(l:_) = getIndentedGroupsBy ((== indentation l) . indentation) ll
-- |
-- > getIndentedGroupsBy (" H" `isPrefixOf`) [" H1", " l1", " l2", " H2", " l3"] = [[" H1", " l1", " l2"], [" H2", " l3"]]
getIndentedGroupsBy :: (T.Text -> Bool) -> [T.Text] -> [[T.Text]]
getIndentedGroupsBy pred inp = case dropWhile (not.pred) inp of
(l:ll) -> case span (\l' -> indentation l < indentation l') ll of
(indented, rest) -> (l:indented) : getIndentedGroupsBy pred rest
_ -> []
indentation :: T.Text -> Int
indentation = T.length . T.takeWhile isSpace
suggestExtendImport :: ExportsMap -> ParsedSource -> Diagnostic -> [(T.Text, CodeActionKind, Rewrite)]
suggestExtendImport exportsMap (L _ HsModule {hsmodImports}) Diagnostic{_range=_range,..}
| Just [binding, mod, srcspan] <-
matchRegexUnifySpaces _message
"Perhaps you want to add ‘([^’]*)’ to the import list in the import of ‘([^’]*)’ *\\((.*)\\).$"
= suggestions hsmodImports binding mod srcspan
| Just (binding, mod_srcspan) <-
matchRegExMultipleImports _message
= mod_srcspan >>= uncurry (suggestions hsmodImports binding)
| otherwise = []
where
suggestions decls binding mod srcspan
| range <- case [ x | (x,"") <- readSrcSpan (T.unpack srcspan)] of
[s] -> let x = realSrcSpanToRange s
in x{_end = (_end x){_character = succ (_character (_end x))}}
_ -> error "bug in srcspan parser",
Just decl <- findImportDeclByRange decls range,
Just ident <- lookupExportMap binding mod
= [ ( "Add " <> renderImportStyle importStyle <> " to the import list of " <> mod
, quickFixImportKind' "extend" importStyle
, uncurry extendImport (unImportStyle importStyle) decl
)
| importStyle <- NE.toList $ importStyles ident
]
| otherwise = []
lookupExportMap binding mod
| Just match <- Map.lookup binding (getExportsMap exportsMap)
, [ident] <- filter (\ident -> moduleNameText ident == mod) (Set.toList match)
= Just ident
-- fallback to using GHC suggestion even though it is not always correct
| otherwise
= Just IdentInfo
{ name = binding
, rendered = binding
, parent = Nothing
, isDatacon = False
, moduleNameText = mod}
data HidingMode
= HideOthers [ModuleTarget]
| ToQualified
Bool
-- ^ Parenthesised?
ModuleName
deriving (Show)
data ModuleTarget
= ExistingImp (NonEmpty (LImportDecl GhcPs))
| ImplicitPrelude [LImportDecl GhcPs]
deriving (Show)
targetImports :: ModuleTarget -> [LImportDecl GhcPs]
targetImports (ExistingImp ne) = NE.toList ne
targetImports (ImplicitPrelude xs) = xs
oneAndOthers :: [a] -> [(a, [a])]
oneAndOthers = go
where
go [] = []
go (x : xs) = (x, xs) : map (second (x :)) (go xs)
isPreludeImplicit :: DynFlags -> Bool
isPreludeImplicit = xopt Lang.ImplicitPrelude
-- | Suggests disambiguation for ambiguous symbols.
suggestImportDisambiguation ::
DynFlags ->
Maybe T.Text ->
ParsedSource ->
Diagnostic ->
[(T.Text, [Either TextEdit Rewrite])]
suggestImportDisambiguation df (Just txt) ps@(L _ HsModule {hsmodImports}) diag@Diagnostic {..}
| Just [ambiguous] <-
matchRegexUnifySpaces
_message
"Ambiguous occurrence ‘([^’]+)’"
, Just modules <-
map last
<$> allMatchRegexUnifySpaces _message "imported from ‘([^’]+)’" =
suggestions ambiguous modules
| otherwise = []
where
locDic =
fmap (NE.fromList . DL.toList) $
Map.fromListWith (<>) $
map
( \i@(L _ idecl) ->
( T.pack $ moduleNameString $ unLoc $ ideclName idecl
, DL.singleton i
)
)
hsmodImports
toModuleTarget "Prelude"
| isPreludeImplicit df
= Just $ ImplicitPrelude $
maybe [] NE.toList (Map.lookup "Prelude" locDic)
toModuleTarget mName = ExistingImp <$> Map.lookup mName locDic
parensed =
"(" `T.isPrefixOf` T.strip (textInRange _range txt)
suggestions symbol mods
| Just targets <- mapM toModuleTarget mods =
sortOn fst
[ ( renderUniquify mode modNameText symbol
, disambiguateSymbol ps diag symbol mode
)
| (modTarget, restImports) <- oneAndOthers targets
, let modName = targetModuleName modTarget
modNameText = T.pack $ moduleNameString modName
, mode <-
HideOthers restImports :
[ ToQualified parensed qual
| ExistingImp imps <- [modTarget]
, L _ qual <- nubOrd $ mapMaybe (ideclAs . unLoc)
$ NE.toList imps
]
++ [ToQualified parensed modName
| any (occursUnqualified symbol . unLoc)
(targetImports modTarget)
|| case modTarget of
ImplicitPrelude{} -> True
_ -> False
]
]
| otherwise = []
renderUniquify HideOthers {} modName symbol =
"Use " <> modName <> " for " <> symbol <> ", hiding other imports"
renderUniquify (ToQualified _ qual) _ symbol =
"Replace with qualified: "
<> T.pack (moduleNameString qual)
<> "."
<> symbol
suggestImportDisambiguation _ _ _ _ = []
occursUnqualified :: T.Text -> ImportDecl GhcPs -> Bool
occursUnqualified symbol ImportDecl{..}
| isNothing ideclAs = Just False /=
-- I don't find this particularly comprehensible,
-- but HLint suggested me to do so...
(ideclHiding <&> \(isHiding, L _ ents) ->
let occurs = any ((symbol `symbolOccursIn`) . unLoc) ents
in isHiding && not occurs || not isHiding && occurs
)
occursUnqualified _ _ = False
symbolOccursIn :: T.Text -> IE GhcPs -> Bool
symbolOccursIn symb = any ((== symb). showNameWithoutUniques) . ieNames
targetModuleName :: ModuleTarget -> ModuleName
targetModuleName ImplicitPrelude{} = mkModuleName "Prelude"
targetModuleName (ExistingImp (L _ ImportDecl{..} :| _)) =
unLoc ideclName
targetModuleName (ExistingImp _) =
error "Cannot happen!"
disambiguateSymbol ::
ParsedSource ->
Diagnostic ->
T.Text ->
HidingMode ->
[Either TextEdit Rewrite]
disambiguateSymbol pm Diagnostic {..} (T.unpack -> symbol) = \case
(HideOthers hiddens0) ->
[ Right $ hideSymbol symbol idecl
| ExistingImp idecls <- hiddens0
, idecl <- NE.toList idecls
]
++ mconcat
[ if null imps
then maybeToList $ Left . snd <$> newImportToEdit (hideImplicitPreludeSymbol $ T.pack symbol) pm
else Right . hideSymbol symbol <$> imps
| ImplicitPrelude imps <- hiddens0
]
(ToQualified parensed qualMod) ->
let occSym = mkVarOcc symbol
rdr = Qual qualMod occSym
in Right <$> [ if parensed
then Rewrite (rangeToSrcSpan "<dummy>" _range) $ \df ->
liftParseAST @(HsExpr GhcPs) df $
prettyPrint $
HsVar @GhcPs noExtField $
L (UnhelpfulSpan "") rdr
else Rewrite (rangeToSrcSpan "<dummy>" _range) $ \df ->
liftParseAST @RdrName df $
prettyPrint $ L (UnhelpfulSpan "") rdr
]
findImportDeclByRange :: [LImportDecl GhcPs] -> Range -> Maybe (LImportDecl GhcPs)
findImportDeclByRange xs range = find (\(L l _)-> srcSpanToRange l == Just range) xs
suggestFixConstructorImport :: Diagnostic -> [(T.Text, TextEdit)]
suggestFixConstructorImport Diagnostic{_range=_range,..}
-- ‘Success’ is a data constructor of ‘Result’
-- To import it use
-- import Data.Aeson.Types( Result( Success ) )
-- or
-- import Data.Aeson.Types( Result(..) ) (lsp-ui)
| Just [constructor, typ] <-
matchRegexUnifySpaces _message
"‘([^’]*)’ is a data constructor of ‘([^’]*)’ To import it use"
= let fixedImport = typ <> "(" <> constructor <> ")"
in [("Fix import of " <> fixedImport, TextEdit _range fixedImport)]
| otherwise = []
-- | Suggests a constraint for a declaration for which a constraint is missing.
suggestConstraint :: DynFlags -> ParsedSource -> Diagnostic -> [(T.Text, Rewrite)]
suggestConstraint df parsedModule diag@Diagnostic {..}
| Just missingConstraint <- findMissingConstraint _message
= let codeAction = if _message =~ ("the type signature for:" :: String)
then suggestFunctionConstraint df parsedModule
else suggestInstanceConstraint df parsedModule
in codeAction diag missingConstraint
| otherwise = []
where
findMissingConstraint :: T.Text -> Maybe T.Text
findMissingConstraint t =
let regex = "(No instance for|Could not deduce) \\((.+)\\) arising from" -- a use of / a do statement
regexImplicitParams = "Could not deduce: (\\?.+) arising from a use of"
match = matchRegexUnifySpaces t regex
matchImplicitParams = matchRegexUnifySpaces t regexImplicitParams
in match <|> matchImplicitParams <&> last
-- | Suggests a constraint for an instance declaration for which a constraint is missing.
suggestInstanceConstraint :: DynFlags -> ParsedSource -> Diagnostic -> T.Text -> [(T.Text, Rewrite)]
suggestInstanceConstraint df (L _ HsModule {hsmodDecls}) Diagnostic {..} missingConstraint
| Just instHead <- instanceHead
= [(actionTitle missingConstraint , appendConstraint (T.unpack missingConstraint) instHead)]
| otherwise = []
where
instanceHead
-- Suggests a constraint for an instance declaration with no existing constraints.
-- • No instance for (Eq a) arising from a use of ‘==’
-- Possible fix: add (Eq a) to the context of the instance declaration
-- • In the expression: x == y
-- In an equation for ‘==’: (Wrap x) == (Wrap y) = x == y
-- In the instance declaration for ‘Eq (Wrap a)’
| Just [instanceDeclaration] <- matchRegexUnifySpaces _message "In the instance declaration for ‘([^`]*)’"
, Just instHead <- findInstanceHead df (T.unpack instanceDeclaration) hsmodDecls
= Just instHead
-- Suggests a constraint for an instance declaration with one or more existing constraints.
-- • Could not deduce (Eq b) arising from a use of ‘==’
-- from the context: Eq a
-- bound by the instance declaration at /path/to/Main.hs:7:10-32
-- Possible fix: add (Eq b) to the context of the instance declaration
-- • In the second argument of ‘(&&)’, namely ‘x' == y'’
-- In the expression: x == y && x' == y'
-- In an equation for ‘==’:
-- (Pair x x') == (Pair y y') = x == y && x' == y'
| Just [instanceLineStr, constraintFirstCharStr]
<- matchRegexUnifySpaces _message "bound by the instance declaration at .+:([0-9]+):([0-9]+)"
, Just (L _ (InstD _ (ClsInstD _ ClsInstDecl {cid_poly_ty = HsIB{hsib_body}})))
<- findDeclContainingLoc (Position (readPositionNumber instanceLineStr) (readPositionNumber constraintFirstCharStr)) hsmodDecls
= Just hsib_body
| otherwise
= Nothing
readPositionNumber :: T.Text -> Int