ghc-mod/ErrMsg.hs

86 lines
2.1 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 _ msg = modifyIORef ref (\ls -> ppMsg src msg : 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 ++ ext
where
spn = head (errMsgSpans err)
msg = errMsgShortDoc err
ext = showMsg (errMsgExtraInfo err)
ppMsg :: SrcSpan -> Message -> String
#if __GLASGOW_HASKELL__ >= 702
ppMsg (UnhelpfulSpan _) _ = undefined
ppMsg (RealSrcSpan src) msg
#else
ppMsg src msg
#endif
= file ++ ":" ++ line ++ ":" ++ col ++ ":" ++ cts ++ "\0"
where
file = takeFileName $ unpackFS (srcSpanFile src)
line = show (srcSpanStartLine src)
col = show (srcSpanStartCol src)
cts = showMsg msg
----------------------------------------------------------------
style :: PprStyle
style = mkUserStyle neverQualify AllTheWay
showMsg :: SDoc -> String
#if __GLASGOW_HASKELL__ >= 702
showMsg d = map toNull $ renderWithStyle d style
#else
showMsg d = map toNull . Pretty.showDocWith PageMode $ d style
#endif
where
toNull '\n' = '\0'
toNull x = x