ghc-mod/Language/Haskell/GhcMod/Gap.hs

{-# LANGUAGE TypeSynonymInstances, FlexibleInstances, CPP #-}

module Language.Haskell.GhcMod.Gap (
    Language.Haskell.GhcMod.Gap.ClsInst
  , mkTarget
  , withStyle
  , setLogAction
  , supportedExtensions
  , getSrcSpan
  , getSrcFile
  , setCtx
  , fOptions
  , toStringBuffer
  , showSeverityCaption
  , setCabalPkg
  , addDevPkgs
  , filterOutChildren
  , infoThing
  , pprInfo
  , HasType(..)
  , errorMsgSpan
  , typeForUser
  , deSugar
#if __GLASGOW_HASKELL__ >= 702
#else
  , module Pretty
#endif
  , showDocWith
  , GapThing(..)
  , fromTyThing
  ) where

import Control.Applicative hiding (empty)
import Control.Monad
import CoreSyn
import Data.List
import Data.Maybe
import Data.Time.Clock
import DataCon (dataConRepType)
import Desugar (deSugarExpr)
import DynFlags
import ErrUtils
import FastString
import HscTypes
import Language.Haskell.GhcMod.GHCChoice
import Language.Haskell.GhcMod.Types hiding (convert)
import NameSet
import Outputable
import PprTyThing
import StringBuffer
import TcType
import Var (varType)

import qualified InstEnv
import qualified Pretty
import qualified StringBuffer as SB
#if __GLASGOW_HASKELL__ >= 707
import FamInstEnv
import ConLike (ConLike(..))
import PatSyn (patSynType)
#else
import TcRnTypes
#endif

#if __GLASGOW_HASKELL__ >= 706
import GHC hiding (ClsInst)
#else
import GHC hiding (Instance)
#endif

#if __GLASGOW_HASKELL__ < 702
import CoreMonad (liftIO)
import Pretty
#endif

#if __GLASGOW_HASKELL__ < 706
import Control.Arrow hiding ((<+>))
import Data.Convertible
#endif

----------------------------------------------------------------
----------------------------------------------------------------
--
#if __GLASGOW_HASKELL__ >= 706
type ClsInst = InstEnv.ClsInst
#else
type ClsInst = InstEnv.Instance
#endif

mkTarget :: TargetId -> Bool -> Maybe (SB.StringBuffer, UTCTime) -> Target
#if __GLASGOW_HASKELL__ >= 706
mkTarget = Target
#else
mkTarget tid allowObjCode = Target tid allowObjCode . (fmap . second) convert
#endif

----------------------------------------------------------------
----------------------------------------------------------------

withStyle :: DynFlags -> PprStyle -> SDoc -> Pretty.Doc
#if __GLASGOW_HASKELL__ >= 706
withStyle = withPprStyleDoc
#else
withStyle _ = withPprStyleDoc
#endif

setLogAction :: DynFlags
             -> (DynFlags -> Severity -> SrcSpan -> PprStyle -> SDoc -> IO ())
             -> DynFlags
setLogAction df f =
#if __GLASGOW_HASKELL__ >= 706
    df { log_action = f }
#else
    df { log_action = f df }
#endif

showDocWith :: DynFlags -> Pretty.Mode -> Pretty.Doc -> String
#if __GLASGOW_HASKELL__ >= 707
-- Pretty.showDocWith disappeard.
-- https://github.com/ghc/ghc/commit/08a3536e4246e323fbcd8040e0b80001950fe9bc
showDocWith dflags mode = Pretty.showDoc mode (pprCols dflags)
#else
showDocWith _ = Pretty.showDocWith
#endif

----------------------------------------------------------------
----------------------------------------------------------------

supportedExtensions :: [String]
#if __GLASGOW_HASKELL__ >= 700
supportedExtensions = supportedLanguagesAndExtensions
#else
supportedExtensions = supportedLanguages
#endif

----------------------------------------------------------------
----------------------------------------------------------------

getSrcSpan :: SrcSpan -> Maybe (Int,Int,Int,Int)
#if __GLASGOW_HASKELL__ >= 702
getSrcSpan (RealSrcSpan spn)
#else
getSrcSpan spn | isGoodSrcSpan spn
#endif
             = Just (srcSpanStartLine spn
                   , srcSpanStartCol spn
                   , srcSpanEndLine spn
                   , srcSpanEndCol spn)
getSrcSpan _ = Nothing

getSrcFile :: SrcSpan -> Maybe String
#if __GLASGOW_HASKELL__ >= 702
getSrcFile (RealSrcSpan spn)       = Just . unpackFS . srcSpanFile $ spn
#else
getSrcFile spn | isGoodSrcSpan spn = Just . unpackFS . srcSpanFile $ spn
#endif
getSrcFile _ = Nothing

----------------------------------------------------------------

toStringBuffer :: [String] -> Ghc StringBuffer
#if __GLASGOW_HASKELL__ >= 702
toStringBuffer = return . stringToStringBuffer . unlines
#else
toStringBuffer = liftIO . stringToStringBuffer . unlines
#endif

----------------------------------------------------------------

fOptions :: [String]
#if __GLASGOW_HASKELL__ >= 704
fOptions = [option | (option,_,_) <- fFlags]
        ++ [option | (option,_,_) <- fWarningFlags]
        ++ [option | (option,_,_) <- fLangFlags]
#elif __GLASGOW_HASKELL__ == 702
fOptions = [option | (option,_,_,_) <- fFlags]
        ++ [option | (option,_,_,_) <- fWarningFlags]
        ++ [option | (option,_,_,_) <- fLangFlags]
#else
fOptions = [option | (option,_,_) <- fFlags]
#endif

----------------------------------------------------------------
----------------------------------------------------------------

setCtx :: [ModSummary] -> Ghc Bool
#if __GLASGOW_HASKELL__ >= 704
setCtx ms = do
#if __GLASGOW_HASKELL__ >= 706
    let modName = IIModule . moduleName . ms_mod
#else
    let modName = IIModule . ms_mod
#endif
    top <- map modName <$> filterM isTop ms
    setContext top
    return (not . null $ top)
#else
setCtx ms = do
    top <- map ms_mod <$> filterM isTop ms
    setContext top []
    return (not . null $ top)
#endif
  where
    isTop mos = lookupMod ||> returnFalse
      where
        lookupMod = lookupModule (ms_mod_name mos) Nothing >> return True
        returnFalse = return False


showSeverityCaption :: Severity -> String
#if __GLASGOW_HASKELL__ >= 706
showSeverityCaption SevWarning = "Warning: "
showSeverityCaption _          = ""
#else
showSeverityCaption = const ""
#endif

----------------------------------------------------------------
----------------------------------------------------------------

setCabalPkg :: DynFlags -> DynFlags
#if __GLASGOW_HASKELL__ >= 707
setCabalPkg dflag = gopt_set dflag Opt_BuildingCabalPackage
#else
setCabalPkg dflag = dopt_set dflag Opt_BuildingCabalPackage
#endif

----------------------------------------------------------------

addDevPkgs :: DynFlags -> [Package] -> DynFlags
addDevPkgs df []   = df
addDevPkgs df pkgs = df''
  where
#if __GLASGOW_HASKELL__ >= 707
    df' = gopt_set df Opt_HideAllPackages
#else
    df' = dopt_set df Opt_HideAllPackages
#endif
    df'' = df' {
        packageFlags = map expose pkgs ++ packageFlags df
      }
    expose (pkg, Nothing) = ExposePackage pkg
    expose (_, Just pid) = ExposePackageId pid

----------------------------------------------------------------
----------------------------------------------------------------

class HasType a where
    getType :: GhcMonad m => TypecheckedModule -> a -> m (Maybe (SrcSpan, Type))


instance HasType (LHsBind Id) where
#if __GLASGOW_HASKELL__ >= 707
    getType _ (L spn FunBind{fun_matches = MG _ in_tys out_typ}) = return $ Just (spn, typ)
      where typ = mkFunTys in_tys out_typ
#else
    getType _ (L spn FunBind{fun_matches = MatchGroup _ typ}) = return $ Just (spn, typ)
#endif
    getType _ _ = return Nothing

----------------------------------------------------------------
----------------------------------------------------------------
-- from ghc/InteractiveUI.hs

filterOutChildren :: (a -> TyThing) -> [a] -> [a]
filterOutChildren get_thing xs
    = [x | x <- xs, not (getName (get_thing x) `elemNameSet` implicits)]
  where
    implicits = mkNameSet [getName t | x <- xs, t <- implicitTyThings (get_thing x)]

infoThing :: String -> Ghc SDoc
infoThing str = do
    names <- parseName str
#if __GLASGOW_HASKELL__ >= 707
    mb_stuffs <- mapM (getInfo False) names
    let filtered = filterOutChildren (\(t,_f,_i,_fam) -> t) (catMaybes mb_stuffs)
#else
    mb_stuffs <- mapM getInfo names
    let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
#endif
    return $ vcat (intersperse (text "") $ map (pprInfo False) filtered)

#if __GLASGOW_HASKELL__ >= 707
pprInfo :: Bool -> (TyThing, GHC.Fixity, [ClsInst], [FamInst]) -> SDoc
pprInfo _ (thing, fixity, insts, famInsts)
    = pprTyThingInContextLoc thing
   $$ show_fixity fixity
   $$ InstEnv.pprInstances insts
   $$ pprFamInsts famInsts
  where
    show_fixity fx
      | fx == defaultFixity = Outputable.empty
      | otherwise           = ppr fx <+> ppr (getName thing)
#else
pprInfo :: PrintExplicitForalls -> (TyThing, GHC.Fixity, [ClsInst]) -> SDoc
pprInfo pefas (thing, fixity, insts)
    = pprTyThingInContextLoc pefas thing
   $$ show_fixity fixity
   $$ vcat (map pprInstance insts)
  where
    show_fixity fx
      | fx == defaultFixity = Outputable.empty
      | otherwise           = ppr fx <+> ppr (getName thing)
#endif

----------------------------------------------------------------
----------------------------------------------------------------

errorMsgSpan :: ErrMsg -> SrcSpan
#if __GLASGOW_HASKELL__ >= 707
errorMsgSpan = errMsgSpan
#else
errorMsgSpan = head . errMsgSpans
#endif

typeForUser :: Type -> SDoc
#if __GLASGOW_HASKELL__ >= 707
typeForUser = pprTypeForUser
#else
typeForUser = pprTypeForUser False
#endif

deSugar :: TypecheckedModule -> LHsExpr Id -> HscEnv
         -> IO (Maybe CoreSyn.CoreExpr)
#if __GLASGOW_HASKELL__ >= 707
deSugar _   e hs_env = snd <$> deSugarExpr hs_env e
#else
deSugar tcm e hs_env = snd <$> deSugarExpr hs_env modu rn_env ty_env e
  where
    modu = ms_mod $ pm_mod_summary $ tm_parsed_module tcm
    tcgEnv = fst $ tm_internals_ tcm
    rn_env = tcg_rdr_env tcgEnv
    ty_env = tcg_type_env tcgEnv
#endif

----------------------------------------------------------------
----------------------------------------------------------------

data GapThing = GtA Type | GtT TyCon | GtN

fromTyThing :: TyThing -> GapThing
fromTyThing (AnId i)                   = GtA $ varType i
#if __GLASGOW_HASKELL__ >= 707
fromTyThing (AConLike (RealDataCon d)) = GtA $ dataConRepType d
fromTyThing (AConLike (PatSynCon p))   = GtA $ patSynType p
#else
fromTyThing (ADataCon d)               = GtA $ dataConRepType d
#endif
fromTyThing (ATyCon t)                 = GtT t
fromTyThing _                          = GtN