ghcide-0.6.0: src/Development/IDE/Plugin/Completions/Logic.hs
{-# LANGUAGE CPP #-}
#include "ghc-api-version.h"
#if MIN_GHC_API_VERSION (8,8,4)
{-# LANGUAGE GADTs#-}
#endif
-- Mostly taken from "haskell-ide-engine"
module Development.IDE.Plugin.Completions.Logic (
CachedCompletions
, cacheDataProducer
, localCompletionsForParsedModule
, WithSnippets(..)
, getCompletions
) where
import Control.Applicative
import Data.Char (isAlphaNum, isUpper)
import Data.Generics
import Data.List.Extra as List hiding (stripPrefix)
import qualified Data.Map as Map
import Data.Maybe (listToMaybe, fromMaybe, mapMaybe)
import qualified Data.Text as T
import qualified Text.Fuzzy as Fuzzy
import HscTypes
import Name
import RdrName
import Type
import Packages
#if MIN_GHC_API_VERSION(8,10,0)
import Predicate (isDictTy)
import GHC.Platform
import Pair
import Coercion
#endif
import Language.Haskell.LSP.Types
import Language.Haskell.LSP.Types.Capabilities
import qualified Language.Haskell.LSP.VFS as VFS
import Development.IDE.Core.Compile
import Development.IDE.Core.PositionMapping
import Development.IDE.Plugin.Completions.Types
import Development.IDE.Spans.Documentation
import Development.IDE.Spans.LocalBindings
import Development.IDE.GHC.Compat as GHC
import Development.IDE.GHC.Error
import Development.IDE.Types.Options
import Development.IDE.Spans.Common
import Development.IDE.GHC.Util
import Outputable (Outputable)
import qualified Data.Set as Set
import ConLike
import GhcPlugins (
flLabel,
unpackFS)
-- 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
-> CiClass
_ -> CiStruct
| isDataOcc oc = CiConstructor
| otherwise = CiVariable
showModName :: ModuleName -> T.Text
showModName = T.pack . moduleNameString
-- mkCompl :: IdeOptions -> CompItem -> CompletionItem
-- mkCompl IdeOptions{..} CI{compKind,insertText, importedFrom,typeText,label,docs} =
-- CompletionItem label kind (List []) ((colon <>) <$> typeText)
-- (Just $ CompletionDocMarkup $ MarkupContent MkMarkdown $ T.intercalate sectionSeparator docs')
-- Nothing Nothing Nothing Nothing (Just insertText) (Just Snippet)
-- Nothing Nothing Nothing Nothing Nothing
mkCompl :: IdeOptions -> CompItem -> CompletionItem
mkCompl IdeOptions{..} CI{compKind,insertText, importedFrom,typeText,label,docs, additionalTextEdits} =
CompletionItem {_label = label,
_kind = kind,
_tags = List [],
_detail = (colon <>) <$> typeText,
_documentation = documentation,
_deprecated = Nothing,
_preselect = Nothing,
_sortText = Nothing,
_filterText = Nothing,
_insertText = Just insertText,
_insertTextFormat = Just Snippet,
_textEdit = Nothing,
_additionalTextEdits = List <$> additionalTextEdits,
_commitCharacters = Nothing,
_command = Nothing,
_xdata = Nothing}
where kind = Just compKind
docs' = imported : spanDocToMarkdown docs
imported = case importedFrom of
Left pos -> "*Defined at '" <> ppr pos <> "'*\n'"
Right mod -> "*Defined in '" <> mod <> "'*\n"
colon = if optNewColonConvention then ": " else ":: "
documentation = Just $ CompletionDocMarkup $
MarkupContent MkMarkdown $
T.intercalate sectionSeparator docs'
mkNameCompItem :: Name -> ModuleName -> Maybe Type -> Maybe Backtick -> SpanDoc -> Maybe (LImportDecl GhcPs) -> CompItem
mkNameCompItem origName origMod thingType isInfix docs !imp = CI{..}
where
compKind = occNameToComKind typeText $ occName origName
importedFrom = Right $ showModName origMod
isTypeCompl = isTcOcc $ occName origName
label = T.pack $ 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 $ T.pack (showGhc t)
| otherwise = Nothing
additionalTextEdits = imp >>= extendImportList (showGhc 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 = T.pack $ "${" <> show i <> ":" <> showGhc t <> "}"
getArgs :: Type -> [Type]
getArgs t
| isPredTy t = []
| isDictTy t = []
| isForAllTy t = getArgs $ snd (splitForAllTys t)
| isFunTy t =
let (args, ret) = splitFunTys t
in if isForAllTy ret
then getArgs ret
else Prelude.filter (not . isDictTy) args
| isPiTy t = getArgs $ snd (splitPiTys t)
#if MIN_GHC_API_VERSION(8,10,0)
| Just (Pair _ t) <- coercionKind <$> isCoercionTy_maybe t
= getArgs t
#else
| isCoercionTy t = maybe [] (getArgs . snd) (splitCoercionType_maybe t)
#endif
| otherwise = []
mkModCompl :: T.Text -> CompletionItem
mkModCompl label =
CompletionItem label (Just CiModule) (List []) Nothing
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing
mkImportCompl :: T.Text -> T.Text -> CompletionItem
mkImportCompl enteredQual label =
CompletionItem m (Just CiModule) (List []) (Just label)
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing
where
m = fromMaybe "" (T.stripPrefix enteredQual label)
mkExtCompl :: T.Text -> CompletionItem
mkExtCompl label =
CompletionItem label (Just CiKeyword) (List []) Nothing
Nothing Nothing Nothing Nothing Nothing Nothing Nothing
Nothing Nothing Nothing Nothing Nothing
mkPragmaCompl :: T.Text -> T.Text -> CompletionItem
mkPragmaCompl label insertText =
CompletionItem label (Just CiKeyword) (List []) Nothing
Nothing Nothing Nothing Nothing Nothing (Just insertText) (Just Snippet)
Nothing Nothing Nothing Nothing Nothing
extendImportList :: String -> LImportDecl GhcPs -> Maybe [TextEdit]
extendImportList name lDecl = let
f (Just range) ImportDecl {ideclHiding} = case ideclHiding of
Just (False, x)
| Set.notMember name (Set.fromList [show y| y <- unLoc x])
-> let
start_pos = _end range
new_start_pos = start_pos {_character = _character start_pos - 1}
-- use to same start_pos to handle situation where we do not have latest edits due to caching of Rules
new_range = Range new_start_pos new_start_pos
-- we cannot wrap mapM_ inside (mapM_) but we need to wrap (<$)
alpha = all isAlphaNum $ filter (\c -> c /= '_') name
result = if alpha then name ++ ", "
else "(" ++ name ++ "), "
in Just [TextEdit new_range (T.pack result)]
| otherwise -> Nothing
_ -> Nothing -- hiding import list and no list
f _ _ = Nothing
src_span = srcSpanToRange . getLoc $ lDecl
in f src_span . unLoc $ lDecl
cacheDataProducer :: HscEnv -> Module -> GlobalRdrEnv -> [LImportDecl GhcPs] -> [ParsedModule] -> IO CachedCompletions
cacheDataProducer packageState curMod rdrEnv limports deps = do
let dflags = hsc_dflags packageState
curModName = moduleName curMod
importMap = Map.fromList [
(getLoc imp, imp)
| imp <- 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 list of all importable Modules from all packages
moduleNames = map showModName (listVisibleModuleNames dflags)
-- The given namespaces for the imported modules (ie. full name, or alias if used)
allModNamesAsNS = map (showModName . asNamespace) importDeclerations
rdrElts = globalRdrEnvElts rdrEnv
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 $! z `mappend` y
getCompls :: [GlobalRdrElt] -> IO ([CompItem],QualCompls)
getCompls = foldMapM getComplsForOne
getComplsForOne :: GlobalRdrElt -> IO ([CompItem],QualCompls)
getComplsForOne (GRE n _ True _) =
(, mempty) <$> toCompItem curMod curModName n Nothing
getComplsForOne (GRE n _ False prov) =
flip foldMapM (map is_decl prov) $ \spec -> do
let originalImportDecl = Map.lookup (is_dloc spec) importMap
compItem <- toCompItem curMod (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 :: Module -> ModuleName -> Name -> Maybe (LImportDecl GhcPs) -> IO [CompItem]
toCompItem m mn n imp' = do
docs <- getDocumentationTryGhc packageState curMod deps n
ty <- catchSrcErrors (hsc_dflags packageState) "completion" $ do
name' <- lookupName packageState m n
return $ name' >>= safeTyThingType
-- use the same pass to also capture any Record snippets that we can collect
record_ty <- catchSrcErrors (hsc_dflags packageState) "record-completion" $ do
name' <- lookupName packageState m n
return $ name' >>= safeTyThingForRecord
let recordCompls = case either (const Nothing) id record_ty of
Just (ctxStr, flds) -> case flds of
[] -> []
_ -> [mkRecordSnippetCompItem ctxStr flds (ppr mn) docs imp']
Nothing -> []
return $ [mkNameCompItem n mn (either (const Nothing) id ty) Nothing docs imp'] ++
recordCompls
(unquals,quals) <- getCompls rdrElts
return $ CC
{ allModNamesAsNS = allModNamesAsNS
, unqualCompls = unquals
, qualCompls = quals
, importableModules = moduleNames
}
-- | Produces completions from the top level declarations of a module.
localCompletionsForParsedModule :: ParsedModule -> CachedCompletions
localCompletionsForParsedModule pm@ParsedModule{pm_parsed_source = L _ HsModule{hsmodDecls, hsmodName}} =
CC { allModNamesAsNS = mempty
, unqualCompls = compls
, qualCompls = mempty
, 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 CiClass Nothing :
[ mkComp id CiFunction (Just $ ppr typ)
| L _ (TypeSig _ ids typ) <- tcdSigs
, id <- ids]
TyClD _ x ->
let generalCompls = [mkComp id cl Nothing
| 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 pm thisModName 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 _ decl <- hsmodDecls
]
mkComp n ctyp ty =
CI ctyp pn (Right thisModName) ty pn Nothing doc (ctyp `elem` [CiStruct, CiClass]) Nothing
where
pn = ppr n
doc = SpanDocText (getDocumentation [pm] n) (SpanDocUris Nothing Nothing)
thisModName = ppr hsmodName
findRecordCompl :: ParsedModule -> T.Text -> TyClDecl GhcPs -> [CompItem]
findRecordCompl pmod mn DataDecl {tcdLName, tcdDataDefn} = result
where
result = [mkRecordSnippetCompItem (T.pack . showGhc . unLoc $ con_name) field_labels mn doc Nothing
| ConDeclH98{..} <- unLoc <$> dd_cons tcdDataDefn
, Just con_details <- [getFlds con_args]
, let field_names = mapMaybe extract con_details
, let field_labels = T.pack . showGhc . unLoc <$> 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
newtype WithSnippets = WithSnippets Bool
toggleSnippets :: ClientCapabilities -> WithSnippets -> CompletionItem -> CompletionItem
toggleSnippets ClientCapabilities { _textDocument } (WithSnippets with) x
| with && supported = x
| otherwise = x { _insertTextFormat = Just PlainText
, _insertText = Nothing
}
where
supported =
Just True == (_textDocument >>= _completion >>= _completionItem >>= _snippetSupport)
-- | Returns the cached completions for the given module and position.
getCompletions
:: IdeOptions
-> CachedCompletions
-> Maybe (ParsedModule, PositionMapping)
-> (Bindings, PositionMapping)
-> VFS.PosPrefixInfo
-> ClientCapabilities
-> WithSnippets
-> IO [CompletionItem]
getCompletions ideOpts CC { allModNamesAsNS, unqualCompls, qualCompls, importableModules}
maybe_parsed (localBindings, bmapping) prefixInfo caps withSnippets = do
let VFS.PosPrefixInfo { fullLine, prefixModule, prefixText } = prefixInfo
enteredQual = if T.null prefixModule then "" else prefixModule <> "."
fullPrefix = enteredQual <> prefixText
{- correct the position by moving 'foo :: Int -> String -> '
^
to 'foo :: Int -> String -> '
^
-}
pos = VFS.cursorPos prefixInfo
filtModNameCompls =
map mkModCompl
$ mapMaybe (T.stripPrefix enteredQual)
$ Fuzzy.simpleFilter fullPrefix allModNamesAsNS
filtCompls = map Fuzzy.original $ Fuzzy.filter prefixText ctxCompls "" "" label False
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 compls
Just ValueContext -> filter (not . isTypeCompl) compls
Just _ -> filter (not . isTypeCompl) compls
-- Add whether the text to insert has backticks
ctxCompls = map (\comp -> 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 = case nameModule_maybe name of
Nothing -> Left $ nameSrcSpan name
Just m -> Right $ ppr m
compls = if T.null prefixModule
then localCompls ++ unqualCompls
else Map.findWithDefault [] prefixModule $ getQualCompls qualCompls
filtListWith f list =
[ f label
| label <- Fuzzy.simpleFilter fullPrefix list
, enteredQual `T.isPrefixOf` label
]
filtListWithSnippet f list suffix =
[ toggleSnippets caps withSnippets (f label (snippet <> suffix))
| (snippet, label) <- list
, Fuzzy.test fullPrefix label
]
filtImportCompls = filtListWith (mkImportCompl enteredQual) importableModules
filtPragmaCompls = filtListWithSnippet mkPragmaCompl validPragmas
filtOptsCompls = filtListWith mkExtCompl
filtKeywordCompls
| T.null prefixModule = filtListWith mkExtCompl (optKeywords ideOpts)
| otherwise = []
stripLeading :: Char -> String -> String
stripLeading _ [] = []
stripLeading c (s:ss)
| s == c = ss
| otherwise = s:ss
result
| "import " `T.isPrefixOf` fullLine
= filtImportCompls
| "{-# language" `T.isPrefixOf` T.toLower fullLine
= filtOptsCompls languagesAndExts
| "{-# options_ghc" `T.isPrefixOf` T.toLower fullLine
= filtOptsCompls (map (T.pack . stripLeading '-') $ flagsForCompletion False)
| "{-# " `T.isPrefixOf` fullLine
= filtPragmaCompls (pragmaSuffix fullLine)
| otherwise
= let uniqueFiltCompls = nubOrdOn insertText filtCompls
in filtModNameCompls ++ map (toggleSnippets caps withSnippets
. mkCompl ideOpts . stripAutoGenerated) uniqueFiltCompls
++ filtKeywordCompls
return result
-- The supported languages and extensions
languagesAndExts :: [T.Text]
#if MIN_GHC_API_VERSION(8,10,0)
languagesAndExts = map T.pack $ GHC.supportedLanguagesAndExtensions ( PlatformMini ArchUnknown OSUnknown )
#else
languagesAndExts = map T.pack GHC.supportedLanguagesAndExtensions
#endif
-- ---------------------------------------------------------------------
-- helper functions for pragmas
-- ---------------------------------------------------------------------
validPragmas :: [(T.Text, T.Text)]
validPragmas =
[ ("LANGUAGE ${1:extension}" , "LANGUAGE")
, ("OPTIONS_GHC -${1:option}" , "OPTIONS_GHC")
, ("INLINE ${1:function}" , "INLINE")
, ("NOINLINE ${1:function}" , "NOINLINE")
, ("INLINABLE ${1:function}" , "INLINABLE")
, ("WARNING ${1:message}" , "WARNING")
, ("DEPRECATED ${1:message}" , "DEPRECATED")
, ("ANN ${1:annotation}" , "ANN")
, ("RULES" , "RULES")
, ("SPECIALIZE ${1:function}" , "SPECIALIZE")
, ("SPECIALIZE INLINE ${1:function}", "SPECIALIZE INLINE")
]
pragmaSuffix :: T.Text -> T.Text
pragmaSuffix fullLine
| "}" `T.isSuffixOf` fullLine = mempty
| otherwise = " #-}"
-- ---------------------------------------------------------------------
-- helper functions for infix backticks
-- ---------------------------------------------------------------------
hasTrailingBacktick :: T.Text -> Position -> Bool
hasTrailingBacktick line Position { _character }
| T.length line > _character = (line `T.index` _character) == '`'
| otherwise = False
isUsedAsInfix :: T.Text -> T.Text -> T.Text -> Position -> Maybe Backtick
isUsedAsInfix line prefixMod prefixText pos
| hasClosingBacktick && hasOpeningBacktick = Just Surrounded
| hasOpeningBacktick = Just LeftSide
| otherwise = Nothing
where
hasOpeningBacktick = openingBacktick line prefixMod prefixText pos
hasClosingBacktick = hasTrailingBacktick line pos
openingBacktick :: T.Text -> T.Text -> T.Text -> Position -> Bool
openingBacktick line prefixModule prefixText Position { _character }
| backtickIndex < 0 = False
| otherwise = (line `T.index` backtickIndex) == '`'
where
backtickIndex :: Int
backtickIndex =
let
prefixLength = T.length prefixText
moduleLength = if prefixModule == ""
then 0
else T.length prefixModule + 1 {- Because of "." -}
in
-- Points to the first letter of either the module or prefix text
_character - (prefixLength + moduleLength) - 1
-- ---------------------------------------------------------------------
-- | Under certain circumstance GHC generates some extra stuff that we
-- don't want in the autocompleted symbols
stripAutoGenerated :: CompItem -> CompItem
stripAutoGenerated ci =
ci {label = stripPrefix (label ci)}
{- When e.g. DuplicateRecordFields is enabled, compiler generates
names like "$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 = T.pack . showGhc . occName . conLikeName $ dc
field_names = T.pack . unpackFS . flLabel <$> conLikeFieldLabels dc
in
Just (ctxStr, field_names)
safeTyThingForRecord _ = Nothing
mkRecordSnippetCompItem :: T.Text -> [T.Text] -> T.Text -> SpanDoc -> Maybe (LImportDecl GhcPs) -> CompItem
mkRecordSnippetCompItem ctxStr compl mn docs imp = r
where
r = CI {
compKind = CiSnippet
, insertText = buildSnippet
, importedFrom = importedFrom
, typeText = Nothing
, label = ctxStr
, isInfix = Nothing
, docs = docs
, isTypeCompl = False
, additionalTextEdits = imp >>= extendImportList (T.unpack 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 <> "}"
importedFrom = Right mn