ghc-mod/Info.hs
2012-02-14 16:19:48 +09:00

150 lines
5.1 KiB
Haskell

{-# LANGUAGE CPP, Rank2Types, TupleSections #-}
module Info (infoExpr, typeExpr) where
import Cabal
import Control.Applicative
import CoreUtils
import Data.Function
import Data.Generics
import Data.List
import Data.Maybe
import Data.Ord as O
import Desugar
import GHC
import GHC.SYB.Utils
import GHCApi
import qualified Gap
import HscTypes
import NameSet
import Outputable
import PprTyThing
import System.Time
import TcRnTypes
import Types
----------------------------------------------------------------
type Expression = String
type ModuleString = String
----------------------------------------------------------------
infoExpr :: Options -> ModuleString -> Expression -> FilePath -> IO String
infoExpr opt modstr expr file = (++ "\n") <$> info opt file modstr expr
info :: Options -> FilePath -> ModuleString -> FilePath -> IO String
info opt fileName modstr expr = inModuleContext opt fileName modstr exprToInfo
where
exprToInfo = infoThing expr
----------------------------------------------------------------
typeExpr :: Options -> ModuleString -> Int -> Int -> FilePath -> IO String
typeExpr opt modstr lineNo colNo file = Info.typeOf opt file modstr lineNo colNo
typeOf :: Options -> FilePath -> ModuleString -> Int -> Int -> IO String
typeOf opt fileName modstr lineNo colNo = inModuleContext opt fileName modstr exprToType
where
exprToType = do
modSum <- getModSummary $ mkModuleName modstr
p <- parseModule modSum
tcm <- typecheckModule p
let es = findExpr tcm lineNo colNo
ts <- catMaybes <$> mapM (getType tcm) es
let sss = map toTup $ sortBy (cmp `on` fst) ts
return $ convert opt sss
toTup :: (SrcSpan, Type) -> ((Int,Int,Int,Int),String)
toTup (spn, typ) = (fourInts spn, pretty 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
findExpr :: TypecheckedModule -> Int -> Int -> [LHsExpr Id]
findExpr tcm line col =
let src = tm_typechecked_source tcm
in listifyStaged TypeChecker f src
where
f :: LHsExpr Id -> Bool
f (L spn _) = isGoodSrcSpan spn && spn `spans` (line, col)
listifyStaged :: Typeable r => Stage -> (r -> Bool) -> GenericQ [r]
listifyStaged s p = everythingStaged s (++) [] ([] `mkQ` (\x -> [x | p x]))
getType :: GhcMonad m => TypecheckedModule -> LHsExpr Id -> m (Maybe (SrcSpan, Type))
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
pretty :: Type -> String
pretty = showSDocForUser neverQualify . 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)
unqual <- getPrintUnqual
return $ showSDocForUser unqual $ 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, [Instance]) -> 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 :: Options -> FilePath -> ModuleString -> Ghc String -> IO String
inModuleContext opt fileName modstr action = withGHC valid
where
valid = do
(file,_) <- initializeGHC opt fileName ["-w"] False
setTargetFile file
load LoadAllTargets
mif setContextFromTarget action invalid
invalid = do
initializeGHC opt fileName ["-w"] False
setTargetBuffer
load LoadAllTargets
mif setContextFromTarget action (return errorMessage)
setTargetBuffer = do
modgraph <- depanal [mkModuleName modstr] True
let imports = concatMap (map (showSDoc . 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 getClockTime
setTargets [Target (TargetModule $ mkModuleName modstr) True (Just (importsBuf, clkTime))]
mif m t e = m >>= \ok -> if ok then t else e
sanitize = fromMaybe "SomeModule" . listToMaybe . words
errorMessage = "Couldn't determine type"
setContextFromTarget :: Ghc Bool
setContextFromTarget = depanal [] False >>= Gap.setCtx