ghc-mod/Language/Haskell/GhcMod/Info.hs
2014-03-27 15:08:07 +09:00

169 lines
6.1 KiB
Haskell

{-# LANGUAGE TupleSections, FlexibleInstances, TypeSynonymInstances, CPP #-}
{-# LANGUAGE Rank2Types #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Language.Haskell.GhcMod.Info (
infoExpr
, info
, typeExpr
, typeOf
) where
import Control.Applicative ((<$>))
import Control.Monad (void)
import CoreMonad (liftIO)
import CoreUtils (exprType)
import Data.Function (on)
import Data.Generics hiding (typeOf)
import Data.List (sortBy)
import Data.Maybe (catMaybes, fromMaybe, listToMaybe)
import Data.Ord as O
import Data.Time.Clock (getCurrentTime)
import GHC
import GHC.SYB.Utils (Stage(TypeChecker), everythingStaged)
import HscTypes (ms_imps)
import Language.Haskell.GhcMod.Doc (showUnqualifiedPage, showUnqualifiedOneLine, showQualifiedPage)
import Language.Haskell.GhcMod.GHCApi
import Language.Haskell.GhcMod.GHCChoice ((||>), goNext)
import qualified Language.Haskell.GhcMod.Gap as Gap
import Language.Haskell.GhcMod.Gap (HasType(..))
import Language.Haskell.GhcMod.Types
import Outputable (ppr)
import TcHsSyn (hsPatType)
----------------------------------------------------------------
data Cmd = Info | Type deriving Eq
----------------------------------------------------------------
-- | Obtaining information of a target expression. (GHCi's info:)
infoExpr :: Options
-> Cradle
-> FilePath -- ^ A target file.
-> ModuleString -- ^ A module name.
-> Expression -- ^ A Haskell expression.
-> IO String
infoExpr opt cradle file modstr expr = (++ "\n") <$> 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 = do
dflag <- getSessionDynFlags
sdoc <- Gap.infoThing expr
return $ showUnqualifiedPage dflag sdoc
----------------------------------------------------------------
instance HasType (LHsExpr Id) where
getType tcm e = do
hs_env <- getSession
mbe <- liftIO $ Gap.deSugar tcm e hs_env
return $ (getLoc e, ) <$> CoreUtils.exprType <$> mbe
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 . Gap.typeForUser
----------------------------------------------------------------
inModuleContext :: Cmd -> Options -> Cradle -> FilePath -> ModuleString -> Ghc String -> String -> Ghc String
inModuleContext _ opt cradle file modstr action errmsg =
valid ||> invalid ||> return errmsg
where
valid = do
void $ initializeFlagsWithCradle opt cradle ["-w:"] False
setTargetFiles [file]
void $ load LoadAllTargets
doif setContextFromTarget action
invalid = do
void $ initializeFlagsWithCradle opt cradle ["-w:"] False
setTargetBuffer
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 <- 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