ghc-mod/Language/Haskell/GhcMod/Info.hs
2013-05-20 14:28:56 +09:00

208 lines
7.3 KiB
Haskell

{-# LANGUAGE TupleSections, FlexibleInstances, TypeSynonymInstances #-}
{-# LANGUAGE Rank2Types #-}
module Language.Haskell.GhcMod.Info (
infoExpr
, info
, typeExpr
, typeOf
) where
import Control.Applicative
import Control.Monad (void, when)
import CoreUtils
import Data.Function
import Data.Generics hiding (typeOf)
import Data.List
import Data.Maybe
import Data.Ord as O
import Data.Time.Clock
import Desugar
import GHC
import GHC.SYB.Utils
import HscTypes
import Language.Haskell.GhcMod.Doc
import Language.Haskell.GhcMod.GHCApi
import Language.Haskell.GhcMod.GHCChoice
import qualified Language.Haskell.GhcMod.Gap as Gap
import Language.Haskell.GhcMod.Types
import NameSet
import Outputable
import PprTyThing
import TcHsSyn (hsPatType)
import TcRnTypes
----------------------------------------------------------------
data Cmd = Info | Type deriving Eq
----------------------------------------------------------------
-- | Obtaining information of a target expression. (GHCi's info:)
infoExpr :: Options
-> Cradle
-> FilePath -- ^ A target file
-> ModuleString -- ^ A module name
-> Expression -- ^ A Haskell expression
-> IO String
infoExpr opt cradle file modstr expr = (++ "\n") <$> withGHCDummyFile (info opt cradle file modstr expr)
-- | Obtaining information of a target expression. (GHCi's info:)
info :: Options
-> Cradle
-> FilePath -- ^ A target file
-> ModuleString -- ^ A module name
-> Expression -- ^ A Haskell expression
-> Ghc String
info opt cradle file modstr expr =
inModuleContext Info opt cradle file modstr exprToInfo "Cannot show info"
where
exprToInfo = infoThing expr
----------------------------------------------------------------
class HasType a where
getType :: GhcMonad m => TypecheckedModule -> a -> m (Maybe (SrcSpan, Type))
instance HasType (LHsExpr Id) where
getType tcm e = do
hs_env <- getSession
(_, mbe) <- Gap.liftIO $ deSugarExpr hs_env modu rn_env ty_env e
return $ (getLoc e, ) <$> CoreUtils.exprType <$> mbe
where
modu = ms_mod $ pm_mod_summary $ tm_parsed_module tcm
rn_env = tcg_rdr_env $ fst $ tm_internals_ tcm
ty_env = tcg_type_env $ fst $ tm_internals_ tcm
instance HasType (LHsBind Id) where
getType _ (L spn FunBind{fun_matches = MatchGroup _ typ}) = return $ Just (spn, typ)
getType _ _ = return Nothing
instance HasType (LPat Id) where
getType _ (L spn pat) = return $ Just (spn, hsPatType pat)
----------------------------------------------------------------
-- | Obtaining type of a target expression. (GHCi's type:)
typeExpr :: Options
-> Cradle
-> FilePath -- ^ A target file
-> ModuleString -- ^ A odule name
-> Int -- ^ Line number
-> Int -- ^ Column number
-> IO String
typeExpr opt cradle file modstr lineNo colNo = withGHCDummyFile $ typeOf opt cradle file modstr lineNo colNo
-- | Obtaining type of a target expression. (GHCi's type:)
typeOf :: Options
-> Cradle
-> FilePath -- ^ A target file
-> ModuleString -- ^ A odule name
-> Int -- ^ Line number
-> Int -- ^ Column number
-> Ghc String
typeOf opt cradle file modstr lineNo colNo =
inModuleContext Type opt cradle file modstr exprToType errmsg
where
exprToType = do
modSum <- getModSummary $ mkModuleName modstr
p <- parseModule modSum
tcm@TypecheckedModule{tm_typechecked_source = tcs} <- typecheckModule p
let bs = listifySpans tcs (lineNo, colNo) :: [LHsBind Id]
es = listifySpans tcs (lineNo, colNo) :: [LHsExpr Id]
ps = listifySpans tcs (lineNo, colNo) :: [LPat Id]
bts <- mapM (getType tcm) bs
ets <- mapM (getType tcm) es
pts <- mapM (getType tcm) ps
dflag <- getSessionDynFlags
let sss = map (toTup dflag) $ sortBy (cmp `on` fst) $ catMaybes $ concat [ets, bts, pts]
return $ convert opt sss
toTup :: DynFlags -> (SrcSpan, Type) -> ((Int,Int,Int,Int),String)
toTup dflag (spn, typ) = (fourInts spn, pretty dflag typ)
fourInts :: SrcSpan -> (Int,Int,Int,Int)
fourInts = fromMaybe (0,0,0,0) . Gap.getSrcSpan
cmp a b
| a `isSubspanOf` b = O.LT
| b `isSubspanOf` a = O.GT
| otherwise = O.EQ
errmsg = convert opt ([] :: [((Int,Int,Int,Int),String)])
listifySpans :: Typeable a => TypecheckedSource -> (Int, Int) -> [Located a]
listifySpans tcs lc = listifyStaged TypeChecker p tcs
where
p (L spn _) = isGoodSrcSpan spn && spn `spans` lc
listifyStaged :: Typeable r => Stage -> (r -> Bool) -> GenericQ [r]
listifyStaged s p = everythingStaged s (++) [] ([] `mkQ` (\x -> [x | p x]))
pretty :: DynFlags -> Type -> String
pretty dflag = showUnqualifiedOneLine dflag . pprTypeForUser False
----------------------------------------------------------------
-- from ghc/InteractiveUI.hs
infoThing :: String -> Ghc String
infoThing str = do
names <- parseName str
mb_stuffs <- mapM getInfo names
let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
dflag <- getSessionDynFlags
return $ showUnqualifiedPage dflag $ vcat (intersperse (text "") $ map (pprInfo False) filtered)
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)]
pprInfo :: PrintExplicitForalls -> (TyThing, GHC.Fixity, [Gap.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)
----------------------------------------------------------------
inModuleContext :: Cmd -> Options -> Cradle -> FilePath -> ModuleString -> Ghc String -> String -> Ghc String
inModuleContext cmd opt cradle file modstr action errmsg =
valid ||> invalid ||> return errmsg
where
valid = do
void $ initializeFlagsWithCradle opt cradle ["-w:"] False
when (cmd == Info) setSlowDynFlags
setTargetFile file
checkSlowAndSet
void $ load LoadAllTargets
doif setContextFromTarget action
invalid = do
void $ initializeFlagsWithCradle opt cradle ["-w:"] False
setTargetBuffer
checkSlowAndSet
void $ load LoadAllTargets
doif setContextFromTarget action
setTargetBuffer = do
modgraph <- depanal [mkModuleName modstr] True
dflag <- getSessionDynFlags
let imports = concatMap (map (showQualifiedPage dflag . ppr . unLoc)) $
map ms_imps modgraph ++ map ms_srcimps modgraph
moddef = "module " ++ sanitize modstr ++ " where"
header = moddef : imports
importsBuf <- Gap.toStringBuffer header
clkTime <- Gap.liftIO getCurrentTime
setTargets [Gap.mkTarget (TargetModule $ mkModuleName modstr)
True
(Just (importsBuf, clkTime))]
doif m t = m >>= \ok -> if ok then t else goNext
sanitize = fromMaybe "SomeModule" . listToMaybe . words
setContextFromTarget :: Ghc Bool
setContextFromTarget = depanal [] False >>= Gap.setCtx