ghc-mod/ErrMsg.hs
2012-02-13 10:39:37 +09:00

83 lines
2.2 KiB
Haskell

{-# LANGUAGE CPP #-}
module ErrMsg (
LogReader
, setLogger
, handleErrMsg
) where
import Bag
import Control.Applicative
import Data.IORef
import DynFlags
import ErrUtils
import FastString
import GHC
import HscTypes
import Outputable
import System.FilePath
#if __GLASGOW_HASKELL__ < 702
import Pretty
#endif
----------------------------------------------------------------
type LogReader = IO [String]
----------------------------------------------------------------
setLogger :: Bool -> DynFlags -> IO (DynFlags, LogReader)
setLogger False df = return (newdf, undefined)
where
newdf = df { log_action = \_ _ _ _ -> return () }
setLogger True df = do
ref <- newIORef [] :: IO (IORef [String])
let newdf = df { log_action = appendLog ref }
return (newdf, reverse <$> readIORef ref)
where
appendLog ref _ src stl msg = modifyIORef ref (\ls -> ppMsg src msg stl : ls)
----------------------------------------------------------------
handleErrMsg :: SourceError -> Ghc [String]
handleErrMsg = return . errBagToStrList . srcErrorMessages
errBagToStrList :: Bag ErrMsg -> [String]
errBagToStrList = map ppErrMsg . reverse . bagToList
----------------------------------------------------------------
ppErrMsg :: ErrMsg -> String
ppErrMsg err = ppMsg spn msg defaultUserStyle ++ ext
where
spn = head (errMsgSpans err)
msg = errMsgShortDoc err
ext = showMsg (errMsgExtraInfo err) defaultUserStyle
ppMsg :: SrcSpan -> Message -> PprStyle -> String
#if __GLASGOW_HASKELL__ >= 702
ppMsg (RealSrcSpan src) msg stl
#else
ppMsg src msg stl | isGoodSrcSpan src
#endif
= file ++ ":" ++ line ++ ":" ++ col ++ ":" ++ cts ++ "\0"
where
file = takeFileName $ unpackFS (srcSpanFile src)
line = show (srcSpanStartLine src)
col = show (srcSpanStartCol src)
cts = showMsg msg stl
ppMsg _ _ _ = "ghc-mod:0:0:Probably mutual module import occurred\0"
----------------------------------------------------------------
showMsg :: SDoc -> PprStyle -> String
#if __GLASGOW_HASKELL__ >= 702
showMsg d stl = map toNull . renderWithStyle d $ stl
#else
showMsg d stl = map toNull . Pretty.showDocWith PageMode $ d stl
#endif
where
toNull '\n' = '\0'
toNull x = x