ghcide-1.5.0: src/Development/IDE/Plugin/Completions/Logic.hs
{-# LANGUAGE CPP #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE MultiWayIf #-}
-- Mostly taken from "haskell-ide-engine"
module Development.IDE.Plugin.Completions.Logic (
CachedCompletions
, cacheDataProducer
, localCompletionsForParsedModule
, getCompletions
, fromIdentInfo
) where
import Control.Applicative
import Data.Char (isUpper)
import Data.Generics
import Data.List.Extra as List hiding
(stripPrefix)
import qualified Data.Map as Map
import Data.Maybe (fromMaybe, isJust,
listToMaybe,
mapMaybe)
import qualified Data.Text as T
import qualified Text.Fuzzy.Parallel as Fuzzy
import Control.Monad
import Data.Aeson (ToJSON (toJSON))
import Data.Either (fromRight)
import Data.Function (on)
import Data.Functor
import qualified Data.HashMap.Strict as HM
import qualified Data.HashSet as HashSet
import Data.Ord (Down (Down))
import qualified Data.Set as Set
import Development.IDE.Core.Compile
import Development.IDE.Core.PositionMapping
import Development.IDE.GHC.Compat as GHC hiding (ppr)
import Development.IDE.GHC.Compat.Util
import Development.IDE.GHC.Error
import Development.IDE.GHC.Util
import Development.IDE.Plugin.Completions.Types
import Development.IDE.Spans.Common
import Development.IDE.Spans.Documentation
import Development.IDE.Spans.LocalBindings
import Development.IDE.Types.Exports
import Development.IDE.Types.HscEnvEq
import Development.IDE.Types.Options
import Ide.PluginUtils (mkLspCommand)
import Ide.Types (CommandId (..),
PluginId)
import Language.LSP.Types
import Language.LSP.Types.Capabilities
import qualified Language.LSP.VFS as VFS
import Text.Fuzzy.Parallel (Scored (score_),
original)
-- Chunk size used for parallelizing fuzzy matching
chunkSize :: Int
chunkSize = 1000
-- From haskell-ide-engine/hie-plugin-api/Haskell/Ide/Engine/Context.hs
-- | A context of a declaration in the program
-- e.g. is the declaration a type declaration or a value declaration
-- Used for determining which code completions to show
-- TODO: expand this with more contexts like classes or instances for
-- smarter code completion
data Context = TypeContext
| ValueContext
| ModuleContext String -- ^ module context with module name
| ImportContext String -- ^ import context with module name
| ImportListContext String -- ^ import list context with module name
| ImportHidingContext String -- ^ import hiding context with module name
| ExportContext -- ^ List of exported identifiers from the current module
deriving (Show, Eq)
-- | Generates a map of where the context is a type and where the context is a value
-- i.e. where are the value decls and the type decls
getCContext :: Position -> ParsedModule -> Maybe Context
getCContext pos pm
| Just (L r modName) <- moduleHeader
, pos `isInsideSrcSpan` r
= Just (ModuleContext (moduleNameString modName))
| Just (L r _) <- exportList
, pos `isInsideSrcSpan` r
= Just ExportContext
| Just ctx <- something (Nothing `mkQ` go `extQ` goInline) decl
= Just ctx
| Just ctx <- something (Nothing `mkQ` importGo) imports
= Just ctx
| otherwise
= Nothing
where decl = hsmodDecls $ unLoc $ pm_parsed_source pm
moduleHeader = hsmodName $ unLoc $ pm_parsed_source pm
exportList = hsmodExports $ unLoc $ pm_parsed_source pm
imports = hsmodImports $ unLoc $ pm_parsed_source pm
go :: LHsDecl GhcPs -> Maybe Context
go (L r SigD {})
| pos `isInsideSrcSpan` r = Just TypeContext
| otherwise = Nothing
go (L r GHC.ValD {})
| pos `isInsideSrcSpan` r = Just ValueContext
| otherwise = Nothing
go _ = Nothing
goInline :: GHC.LHsType GhcPs -> Maybe Context
goInline (GHC.L r _)
| pos `isInsideSrcSpan` r = Just TypeContext
goInline _ = Nothing
importGo :: GHC.LImportDecl GhcPs -> Maybe Context
importGo (L r impDecl)
| pos `isInsideSrcSpan` r
= importInline importModuleName (ideclHiding impDecl)
<|> Just (ImportContext importModuleName)
| otherwise = Nothing
where importModuleName = moduleNameString $ unLoc $ ideclName impDecl
importInline :: String -> Maybe (Bool, GHC.Located [LIE GhcPs]) -> Maybe Context
importInline modName (Just (True, L r _))
| pos `isInsideSrcSpan` r = Just $ ImportHidingContext modName
| otherwise = Nothing
importInline modName (Just (False, L r _))
| pos `isInsideSrcSpan` r = Just $ ImportListContext modName
| otherwise = Nothing
importInline _ _ = Nothing
occNameToComKind :: Maybe T.Text -> OccName -> CompletionItemKind
occNameToComKind ty oc
| isVarOcc oc = case occNameString oc of
i:_ | isUpper i -> CiConstructor
_ -> CiFunction
| isTcOcc oc = case ty of
Just t
| "Constraint" `T.isSuffixOf` t
-> CiInterface
_ -> CiStruct
| isDataOcc oc = CiConstructor
| otherwise = CiVariable
showModName :: ModuleName -> T.Text
showModName = T.pack . moduleNameString
mkCompl :: PluginId -> IdeOptions -> CompItem -> CompletionItem
mkCompl
pId
IdeOptions {..}
CI
{ compKind,
isInfix,
insertText,
provenance,
typeText,
label,
docs,
additionalTextEdits
} = do
let mbCommand = mkAdditionalEditsCommand pId `fmap` additionalTextEdits
let ci = CompletionItem
{_label = label,
_kind = kind,
_tags = Nothing,
_detail =
case (typeText, provenance) of
(Just t,_) | not(T.null t) -> Just $ colon <> t
(_, ImportedFrom mod) -> Just $ "from " <> mod
(_, DefinedIn mod) -> Just $ "from " <> mod
_ -> Nothing,
_documentation = documentation,
_deprecated = Nothing,
_preselect = Nothing,
_sortText = Nothing,
_filterText = Nothing,
_insertText = Just insertText,
_insertTextFormat = Just Snippet,
_insertTextMode = Nothing,
_textEdit = Nothing,
_additionalTextEdits = Nothing,
_commitCharacters = Nothing,
_command = mbCommand,
_xdata = Nothing}
removeSnippetsWhen (isJust isInfix) ci
where kind = Just compKind
docs' = imported : spanDocToMarkdown docs
imported = case provenance of
Local pos -> "*Defined at " <> pprLineCol (srcSpanStart pos) <> " in this module*\n'"
ImportedFrom mod -> "*Imported from '" <> mod <> "'*\n"
DefinedIn mod -> "*Defined in '" <> mod <> "'*\n"
colon = if optNewColonConvention then ": " else ":: "
documentation = Just $ CompletionDocMarkup $
MarkupContent MkMarkdown $
T.intercalate sectionSeparator docs'
pprLineCol :: SrcLoc -> T.Text
pprLineCol (UnhelpfulLoc fs) = T.pack $ unpackFS fs
pprLineCol (RealSrcLoc loc _) =
"line " <> ppr(srcLocLine loc) <> ", column " <> ppr(srcLocCol loc)
mkAdditionalEditsCommand :: PluginId -> ExtendImport -> Command
mkAdditionalEditsCommand pId edits =
mkLspCommand pId (CommandId extendImportCommandId) "extend import" (Just [toJSON edits])
mkNameCompItem :: Uri -> Maybe T.Text -> OccName -> Provenance -> Maybe Type -> Maybe Backtick -> SpanDoc -> Maybe (LImportDecl GhcPs) -> CompItem
mkNameCompItem doc thingParent origName provenance thingType isInfix docs !imp = CI {..}
where
compKind = occNameToComKind typeText origName
isTypeCompl = isTcOcc origName
label = stripPrefix $ showGhc origName
insertText = case isInfix of
Nothing -> case getArgText <$> thingType of
Nothing -> label
Just argText -> label <> " " <> argText
Just LeftSide -> label <> "`"
Just Surrounded -> label
typeText
| Just t <- thingType = Just . stripForall $ showGhc t
| otherwise = Nothing
additionalTextEdits =
imp <&> \x ->
ExtendImport
{ doc,
thingParent,
importName = showModName $ unLoc $ ideclName $ unLoc x,
importQual = getImportQual x,
newThing = showNameWithoutUniques origName
}
stripForall :: T.Text -> T.Text
stripForall t
| T.isPrefixOf "forall" t =
-- We drop 2 to remove the '.' and the space after it
T.drop 2 (T.dropWhile (/= '.') t)
| otherwise = t
getArgText :: Type -> T.Text
getArgText typ = argText
where
argTypes = getArgs typ
argText :: T.Text
argText = mconcat $ List.intersperse " " $ zipWithFrom snippet 1 argTypes
snippet :: Int -> Type -> T.Text
snippet i t = case t of
(TyVarTy _) -> noParensSnippet
(LitTy _) -> noParensSnippet
(TyConApp _ []) -> noParensSnippet
_ -> snippetText i ("(" <> showGhc t <> ")")
where
noParensSnippet = snippetText i (showGhc t)
snippetText i t = "${" <> T.pack (show i) <> ":" <> t <> "}"
getArgs :: Type -> [Type]
getArgs t
| isPredTy t = []
| isDictTy t = []
| isForAllTy t = getArgs $ snd (splitForAllTyCoVars t)
| isFunTy t =
let (args, ret) = splitFunTys t
in if isForAllTy ret
then getArgs ret
else Prelude.filter (not . isDictTy) $ map scaledThing args
| isPiTy t = getArgs $ snd (splitPiTys t)
#if MIN_VERSION_ghc(8,10,0)
| Just (Pair _ t) <- coercionKind <$> isCoercionTy_maybe t
= getArgs t
#else
| isCoercionTy t = maybe [] (getArgs . snd) (splitCoercionType_maybe t)
#endif
| otherwise = []
mkModCompl :: T.Text -> CompletionItem
mkModCompl label =
CompletionItem label (Just CiModule) Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing
mkModuleFunctionImport :: T.Text -> T.Text -> CompletionItem
mkModuleFunctionImport moduleName label =
CompletionItem label (Just CiFunction) Nothing (Just moduleName)
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing
mkImportCompl :: T.Text -> T.Text -> CompletionItem
mkImportCompl enteredQual label =
CompletionItem m (Just CiModule) Nothing (Just label)
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing
where
m = fromMaybe "" (T.stripPrefix enteredQual label)
mkExtCompl :: T.Text -> CompletionItem
mkExtCompl label =
CompletionItem label (Just CiKeyword) Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing Nothing
fromIdentInfo :: Uri -> IdentInfo -> Maybe T.Text -> CompItem
fromIdentInfo doc IdentInfo{..} q = CI
{ compKind= occNameToComKind Nothing name
, insertText=rendered
, provenance = DefinedIn moduleNameText
, typeText=Nothing
, label=rendered
, isInfix=Nothing
, docs=emptySpanDoc
, isTypeCompl= not isDatacon && isUpper (T.head rendered)
, additionalTextEdits= Just $
ExtendImport
{ doc,
thingParent = parent,
importName = moduleNameText,
importQual = q,
newThing = rendered
}
}
cacheDataProducer :: Uri -> HscEnvEq -> Module -> GlobalRdrEnv-> GlobalRdrEnv -> [LImportDecl GhcPs] -> IO CachedCompletions
cacheDataProducer uri env curMod globalEnv inScopeEnv limports = do
let
packageState = hscEnv env
curModName = moduleName curMod
curModNameText = ppr curModName
importMap = Map.fromList [ (l, imp) | imp@(L (RealSrcSpan l _) _) <- limports ]
iDeclToModName :: ImportDecl name -> ModuleName
iDeclToModName = unLoc . ideclName
asNamespace :: ImportDecl name -> ModuleName
asNamespace imp = maybe (iDeclToModName imp) GHC.unLoc (ideclAs imp)
-- Full canonical names of imported modules
importDeclerations = map unLoc limports
-- The given namespaces for the imported modules (ie. full name, or alias if used)
allModNamesAsNS = map (showModName . asNamespace) importDeclerations
rdrElts = globalRdrEnvElts globalEnv
foldMapM :: (Foldable f, Monad m, Monoid b) => (a -> m b) -> f a -> m b
foldMapM f xs = foldr step return xs mempty where
step x r z = f x >>= \y -> r $! z `mappend` y
getCompls :: [GlobalRdrElt] -> IO ([CompItem],QualCompls)
getCompls = foldMapM getComplsForOne
getComplsForOne :: GlobalRdrElt -> IO ([CompItem],QualCompls)
getComplsForOne (GRE n par True _) =
(, mempty) <$> toCompItem par curMod curModNameText n Nothing
getComplsForOne (GRE n par False prov) =
flip foldMapM (map is_decl prov) $ \spec -> do
let originalImportDecl = do
-- we don't want to extend import if it's already in scope
guard . null $ lookupGRE_Name inScopeEnv n
-- or if it doesn't have a real location
loc <- realSpan $ is_dloc spec
Map.lookup loc importMap
compItem <- toCompItem par curMod (ppr $ is_mod spec) n originalImportDecl
let unqual
| is_qual spec = []
| otherwise = compItem
qual
| is_qual spec = Map.singleton asMod compItem
| otherwise = Map.fromList [(asMod,compItem),(origMod,compItem)]
asMod = showModName (is_as spec)
origMod = showModName (is_mod spec)
return (unqual,QualCompls qual)
toCompItem :: Parent -> Module -> T.Text -> Name -> Maybe (LImportDecl GhcPs) -> IO [CompItem]
toCompItem par m mn n imp' = do
docs <- getDocumentationTryGhc packageState curMod n
let (mbParent, originName) = case par of
NoParent -> (Nothing, nameOccName n)
ParentIs n' -> (Just . T.pack $ printName n', nameOccName n)
FldParent n' lbl -> (Just . T.pack $ printName n', maybe (nameOccName n) mkVarOccFS lbl)
tys <- catchSrcErrors (hsc_dflags packageState) "completion" $ do
name' <- lookupName packageState m n
return ( name' >>= safeTyThingType
, guard (isJust mbParent) >> name' >>= safeTyThingForRecord
)
let (ty, record_ty) = fromRight (Nothing, Nothing) tys
let recordCompls = case record_ty of
Just (ctxStr, flds) | not (null flds) ->
[mkRecordSnippetCompItem uri mbParent ctxStr flds (ImportedFrom mn) docs imp']
_ -> []
return $ mkNameCompItem uri mbParent originName (ImportedFrom mn) ty Nothing docs imp'
: recordCompls
(unquals,quals) <- getCompls rdrElts
-- The list of all importable Modules from all packages
moduleNames <- maybe [] (map showModName) <$> envVisibleModuleNames env
return $ CC
{ allModNamesAsNS = allModNamesAsNS
, unqualCompls = unquals
, qualCompls = quals
, anyQualCompls = []
, importableModules = moduleNames
}
-- | Produces completions from the top level declarations of a module.
localCompletionsForParsedModule :: Uri -> ParsedModule -> CachedCompletions
localCompletionsForParsedModule uri pm@ParsedModule{pm_parsed_source = L _ HsModule{hsmodDecls}} =
CC { allModNamesAsNS = mempty
, unqualCompls = compls
, qualCompls = mempty
, anyQualCompls = []
, importableModules = mempty
}
where
typeSigIds = Set.fromList
[ id
| L _ (SigD _ (TypeSig _ ids _)) <- hsmodDecls
, L _ id <- ids
]
hasTypeSig = (`Set.member` typeSigIds) . unLoc
compls = concat
[ case decl of
SigD _ (TypeSig _ ids typ) ->
[mkComp id CiFunction (Just $ ppr typ) | id <- ids]
ValD _ FunBind{fun_id} ->
[ mkComp fun_id CiFunction Nothing
| not (hasTypeSig fun_id)
]
ValD _ PatBind{pat_lhs} ->
[mkComp id CiVariable Nothing
| VarPat _ id <- listify (\(_ :: Pat GhcPs) -> True) pat_lhs]
TyClD _ ClassDecl{tcdLName, tcdSigs} ->
mkComp tcdLName CiInterface (Just $ ppr tcdLName) :
[ mkComp id CiFunction (Just $ ppr typ)
| L _ (ClassOpSig _ _ ids typ) <- tcdSigs
, id <- ids]
TyClD _ x ->
let generalCompls = [mkComp id cl (Just $ ppr $ tcdLName x)
| id <- listify (\(_ :: Located(IdP GhcPs)) -> True) x
, let cl = occNameToComKind Nothing (rdrNameOcc $ unLoc id)]
-- here we only have to look at the outermost type
recordCompls = findRecordCompl uri pm (Local pos) x
in
-- the constructors and snippets will be duplicated here giving the user 2 choices.
generalCompls ++ recordCompls
ForD _ ForeignImport{fd_name,fd_sig_ty} ->
[mkComp fd_name CiVariable (Just $ ppr fd_sig_ty)]
ForD _ ForeignExport{fd_name,fd_sig_ty} ->
[mkComp fd_name CiVariable (Just $ ppr fd_sig_ty)]
_ -> []
| L pos decl <- hsmodDecls,
let mkComp = mkLocalComp pos
]
mkLocalComp pos n ctyp ty =
CI ctyp pn (Local pos) ensureTypeText pn Nothing doc (ctyp `elem` [CiStruct, CiInterface]) Nothing
where
-- when sorting completions, we use the presence of typeText
-- to tell local completions and global completions apart
-- instead of using the empty string here, we should probably introduce a new field...
ensureTypeText = Just $ fromMaybe "" ty
pn = ppr n
doc = SpanDocText (getDocumentation [pm] n) (SpanDocUris Nothing Nothing)
findRecordCompl :: Uri -> ParsedModule -> Provenance -> TyClDecl GhcPs -> [CompItem]
findRecordCompl uri pmod mn DataDecl {tcdLName, tcdDataDefn} = result
where
result = [mkRecordSnippetCompItem uri (Just $ showNameWithoutUniques $ unLoc tcdLName)
(showGhc . unLoc $ con_name) field_labels mn doc Nothing
| ConDeclH98{..} <- unLoc <$> dd_cons tcdDataDefn
, Just con_details <- [getFlds con_args]
, let field_names = mapMaybe extract con_details
, let field_labels = showGhc . unLoc <$> field_names
, (not . List.null) field_labels
]
doc = SpanDocText (getDocumentation [pmod] tcdLName) (SpanDocUris Nothing Nothing)
getFlds :: HsConDetails arg (Located [LConDeclField GhcPs]) -> Maybe [ConDeclField GhcPs]
getFlds conArg = case conArg of
RecCon rec -> Just $ unLoc <$> unLoc rec
PrefixCon _ -> Just []
_ -> Nothing
extract ConDeclField{..}
-- TODO: Why is cd_fld_names a list?
| Just fld_name <- rdrNameFieldOcc . unLoc <$> listToMaybe cd_fld_names = Just fld_name
| otherwise = Nothing
-- XConDeclField
extract _ = Nothing
findRecordCompl _ _ _ _ = []
ppr :: Outputable a => a -> T.Text
ppr = T.pack . prettyPrint
toggleSnippets :: ClientCapabilities -> CompletionsConfig -> CompletionItem -> CompletionItem
toggleSnippets ClientCapabilities {_textDocument} CompletionsConfig{..} =
removeSnippetsWhen (not $ enableSnippets && supported)
where
supported =
Just True == (_textDocument >>= _completion >>= _completionItem >>= _snippetSupport)
toggleAutoExtend :: CompletionsConfig -> CompItem -> CompItem
toggleAutoExtend CompletionsConfig{enableAutoExtend=False} x = x {additionalTextEdits = Nothing}
toggleAutoExtend _ x = x
removeSnippetsWhen :: Bool -> CompletionItem -> CompletionItem
removeSnippetsWhen condition x =
if condition
then
x
{ _insertTextFormat = Just PlainText,
_insertText = Nothing
}
else x
-- | Returns the cached completions for the given module and position.
getCompletions
:: PluginId
-> IdeOptions
-> CachedCompletions
-> Maybe (ParsedModule, PositionMapping)
-> (Bindings, PositionMapping)
-> VFS.PosPrefixInfo
-> ClientCapabilities
-> CompletionsConfig
-> HM.HashMap T.Text (HashSet.HashSet IdentInfo)
-> IO [Scored CompletionItem]
getCompletions plId ideOpts CC {allModNamesAsNS, anyQualCompls, unqualCompls, qualCompls, importableModules}
maybe_parsed (localBindings, bmapping) prefixInfo caps config moduleExportsMap = do
let VFS.PosPrefixInfo { fullLine, prefixModule, prefixText } = prefixInfo
enteredQual = if T.null prefixModule then "" else prefixModule <> "."
fullPrefix = enteredQual <> prefixText
-- Boolean labels to tag suggestions as qualified (or not)
qual = not(T.null prefixModule)
notQual = False
{- correct the position by moving 'foo :: Int -> String -> '
^
to 'foo :: Int -> String -> '
^
-}
pos = VFS.cursorPos prefixInfo
maxC = maxCompletions config
filtModNameCompls :: [Scored CompletionItem]
filtModNameCompls =
(fmap.fmap) mkModCompl
$ Fuzzy.simpleFilter chunkSize maxC fullPrefix
$ (if T.null enteredQual then id else mapMaybe (T.stripPrefix enteredQual))
allModNamesAsNS
filtCompls = Fuzzy.filter chunkSize maxC prefixText ctxCompls "" "" (label . snd)
where
mcc = case maybe_parsed of
Nothing -> Nothing
Just (pm, pmapping) ->
let PositionMapping pDelta = pmapping
position' = fromDelta pDelta pos
lpos = lowerRange position'
hpos = upperRange position'
in getCContext lpos pm <|> getCContext hpos pm
-- completions specific to the current context
ctxCompls' = case mcc of
Nothing -> compls
Just TypeContext -> filter ( isTypeCompl . snd) compls
Just ValueContext -> filter (not . isTypeCompl . snd) compls
Just _ -> filter (not . isTypeCompl . snd) compls
-- Add whether the text to insert has backticks
ctxCompls = (fmap.fmap) (\comp -> toggleAutoExtend config $ comp { isInfix = infixCompls }) ctxCompls'
infixCompls :: Maybe Backtick
infixCompls = isUsedAsInfix fullLine prefixModule prefixText pos
PositionMapping bDelta = bmapping
oldPos = fromDelta bDelta $ VFS.cursorPos prefixInfo
startLoc = lowerRange oldPos
endLoc = upperRange oldPos
localCompls = map (uncurry localBindsToCompItem) $ getFuzzyScope localBindings startLoc endLoc
localBindsToCompItem :: Name -> Maybe Type -> CompItem
localBindsToCompItem name typ = CI ctyp pn thisModName ty pn Nothing emptySpanDoc (not $ isValOcc occ) Nothing
where
occ = nameOccName name
ctyp = occNameToComKind Nothing occ
pn = ppr name
ty = ppr <$> typ
thisModName = Local $ nameSrcSpan name
compls = if T.null prefixModule
then map (notQual,) localCompls ++ map (qual,) unqualCompls ++ ((notQual,) . ($Nothing) <$> anyQualCompls)
else ((qual,) <$> Map.findWithDefault [] prefixModule (getQualCompls qualCompls))
++ ((notQual,) . ($ Just prefixModule) <$> anyQualCompls)
filtListWith f list =
[ fmap f label
| label <- Fuzzy.simpleFilter chunkSize maxC fullPrefix list
, enteredQual `T.isPrefixOf` original label
]
filtImportCompls = filtListWith (mkImportCompl enteredQual) importableModules
filterModuleExports moduleName = filtListWith $ mkModuleFunctionImport moduleName
filtKeywordCompls
| T.null prefixModule = filtListWith mkExtCompl (optKeywords ideOpts)
| otherwise = []
if
-- TODO: handle multiline imports
| "import " `T.isPrefixOf` fullLine
&& (List.length (words (T.unpack fullLine)) >= 2)
&& "(" `isInfixOf` T.unpack fullLine
-> do
let moduleName = T.pack $ words (T.unpack fullLine) !! 1
funcs = HM.lookupDefault HashSet.empty moduleName moduleExportsMap
funs = map (show . name) $ HashSet.toList funcs
return $ filterModuleExports moduleName $ map T.pack funs
| "import " `T.isPrefixOf` fullLine
-> return filtImportCompls
-- we leave this condition here to avoid duplications and return empty list
-- since HLS implements these completions (#haskell-language-server/pull/662)
| "{-# " `T.isPrefixOf` fullLine
-> return []
| otherwise -> do
-- assumes that nubOrdBy is stable
let uniqueFiltCompls = nubOrdBy (uniqueCompl `on` snd . Fuzzy.original) filtCompls
let compls = (fmap.fmap.fmap) (mkCompl plId ideOpts) uniqueFiltCompls
return $
(fmap.fmap) snd $
sortBy (compare `on` lexicographicOrdering) $
mergeListsBy (flip compare `on` score_)
[ (fmap.fmap) (notQual,) filtModNameCompls
, (fmap.fmap) (notQual,) filtKeywordCompls
, (fmap.fmap.fmap) (toggleSnippets caps config) compls
]
where
-- We use this ordering to alphabetically sort suggestions while respecting
-- all the previously applied ordering sources. These are:
-- 1. Qualified suggestions go first
-- 2. Fuzzy score ranks next
-- 3. In-scope completions rank next
-- 4. label alphabetical ordering next
-- 4. detail alphabetical ordering (proxy for module)
lexicographicOrdering Fuzzy.Scored{score_, original} =
case original of
(isQual, CompletionItem{_label,_detail}) -> do
let isLocal = maybe False (":" `T.isPrefixOf`) _detail
(Down isQual, Down score_, Down isLocal, _label, _detail)
uniqueCompl :: CompItem -> CompItem -> Ordering
uniqueCompl candidate unique =
case compare (label candidate, compKind candidate)
(label unique, compKind unique) of
EQ ->
-- preserve completions for duplicate record fields where the only difference is in the type
-- remove redundant completions with less type info than the previous
if (typeText candidate == typeText unique && isLocalCompletion unique)
-- filter global completions when we already have a local one
|| not(isLocalCompletion candidate) && isLocalCompletion unique
then EQ
else compare (importedFrom candidate, insertText candidate) (importedFrom unique, insertText unique)
other -> other
where
isLocalCompletion ci = isJust(typeText ci)
importedFrom :: CompItem -> T.Text
importedFrom (provenance -> ImportedFrom m) = m
importedFrom (provenance -> DefinedIn m) = m
importedFrom (provenance -> Local _) = "local"
-- ---------------------------------------------------------------------
-- helper functions for infix backticks
-- ---------------------------------------------------------------------
hasTrailingBacktick :: T.Text -> Position -> Bool
hasTrailingBacktick line Position { _character }
| T.length line > _character = (line `T.index` _character) == '`'
| otherwise = False
isUsedAsInfix :: T.Text -> T.Text -> T.Text -> Position -> Maybe Backtick
isUsedAsInfix line prefixMod prefixText pos
| hasClosingBacktick && hasOpeningBacktick = Just Surrounded
| hasOpeningBacktick = Just LeftSide
| otherwise = Nothing
where
hasOpeningBacktick = openingBacktick line prefixMod prefixText pos
hasClosingBacktick = hasTrailingBacktick line pos
openingBacktick :: T.Text -> T.Text -> T.Text -> Position -> Bool
openingBacktick line prefixModule prefixText Position { _character }
| backtickIndex < 0 || backtickIndex > T.length line = False
| otherwise = (line `T.index` backtickIndex) == '`'
where
backtickIndex :: Int
backtickIndex =
let
prefixLength = T.length prefixText
moduleLength = if prefixModule == ""
then 0
else T.length prefixModule + 1 {- Because of "." -}
in
-- Points to the first letter of either the module or prefix text
_character - (prefixLength + moduleLength) - 1
-- ---------------------------------------------------------------------
-- | Under certain circumstance GHC generates some extra stuff that we
-- don't want in the autocompleted symbols
{- When e.g. DuplicateRecordFields is enabled, compiler generates
names like "$sel:accessor:One" and "$sel:accessor:Two" to disambiguate record selectors
https://ghc.haskell.org/trac/ghc/wiki/Records/OverloadedRecordFields/DuplicateRecordFields#Implementation
-}
-- TODO: Turn this into an alex lexer that discards prefixes as if they were whitespace.
stripPrefix :: T.Text -> T.Text
stripPrefix name = T.takeWhile (/=':') $ go prefixes
where
go [] = name
go (p:ps)
| T.isPrefixOf p name = T.drop (T.length p) name
| otherwise = go ps
-- | Prefixes that can occur in a GHC OccName
prefixes :: [T.Text]
prefixes =
[
-- long ones
"$con2tag_"
, "$tag2con_"
, "$maxtag_"
-- four chars
, "$sel:"
, "$tc'"
-- three chars
, "$dm"
, "$co"
, "$tc"
, "$cp"
, "$fx"
-- two chars
, "$W"
, "$w"
, "$m"
, "$b"
, "$c"
, "$d"
, "$i"
, "$s"
, "$f"
, "$r"
, "C:"
, "N:"
, "D:"
, "$p"
, "$L"
, "$f"
, "$t"
, "$c"
, "$m"
]
safeTyThingForRecord :: TyThing -> Maybe (T.Text, [T.Text])
safeTyThingForRecord (AnId _) = Nothing
safeTyThingForRecord (AConLike dc) =
let ctxStr = showGhc . occName . conLikeName $ dc
field_names = T.pack . unpackFS . flLabel <$> conLikeFieldLabels dc
in
Just (ctxStr, field_names)
safeTyThingForRecord _ = Nothing
mkRecordSnippetCompItem :: Uri -> Maybe T.Text -> T.Text -> [T.Text] -> Provenance -> SpanDoc -> Maybe (LImportDecl GhcPs) -> CompItem
mkRecordSnippetCompItem uri parent ctxStr compl importedFrom docs imp = r
where
r = CI {
compKind = CiSnippet
, insertText = buildSnippet
, provenance = importedFrom
, typeText = Nothing
, label = ctxStr
, isInfix = Nothing
, docs = docs
, isTypeCompl = False
, additionalTextEdits = imp <&> \x ->
ExtendImport
{ doc = uri,
thingParent = parent,
importName = showModName $ unLoc $ ideclName $ unLoc x,
importQual = getImportQual x,
newThing = ctxStr
}
}
placeholder_pairs = zip compl ([1..]::[Int])
snippet_parts = map (\(x, i) -> x <> "=${" <> T.pack (show i) <> ":_" <> x <> "}") placeholder_pairs
snippet = T.intercalate (T.pack ", ") snippet_parts
buildSnippet = ctxStr <> " {" <> snippet <> "}"
getImportQual :: LImportDecl GhcPs -> Maybe T.Text
getImportQual (L _ imp)
| isQualifiedImport imp = Just $ T.pack $ moduleNameString $ maybe (unLoc $ ideclName imp) unLoc (ideclAs imp)
| otherwise = Nothing
--------------------------------------------------------------------------------
-- This comes from the GHC.Utils.Misc module (not exported)
-- | Merge an unsorted list of sorted lists, for example:
--
-- > mergeListsBy compare [ [2,5,15], [1,10,100] ] = [1,2,5,10,15,100]
--
-- \( O(n \log{} k) \)
mergeListsBy :: forall a. (a -> a -> Ordering) -> [[a]] -> [a]
mergeListsBy cmp all_lists = merge_lists all_lists
where
-- Implements "Iterative 2-Way merge" described at
-- https://en.wikipedia.org/wiki/K-way_merge_algorithm
-- Merge two sorted lists into one in O(n).
merge2 :: [a] -> [a] -> [a]
merge2 [] ys = ys
merge2 xs [] = xs
merge2 (x:xs) (y:ys) =
case cmp x y of
Prelude.GT -> y : merge2 (x:xs) ys
_ -> x : merge2 xs (y:ys)
-- Merge the first list with the second, the third with the fourth, and so
-- on. The output has half as much lists as the input.
merge_neighbours :: [[a]] -> [[a]]
merge_neighbours [] = []
merge_neighbours [xs] = [xs]
merge_neighbours (xs : ys : lists) =
merge2 xs ys : merge_neighbours lists
-- Since 'merge_neighbours' halves the amount of lists in each iteration,
-- we perform O(log k) iteration. Each iteration is O(n). The total running
-- time is therefore O(n log k).
merge_lists :: [[a]] -> [a]
merge_lists lists =
case merge_neighbours lists of
[] -> []
[xs] -> xs
lists' -> merge_lists lists'