ghc-mod/Language/Haskell/GhcMod/Logger.hs
2014-08-14 20:51:49 +02:00

167 lines
6.2 KiB
Haskell

{-# LANGUAGE CPP #-}
module Language.Haskell.GhcMod.Logger (
withLogger
, withLoggerTwice
, checkErrorPrefix
) where
import Bag (Bag, bagToList, filterBag, unionBags)
import Control.Applicative ((<$>))
import Data.IORef (IORef, newIORef, readIORef, writeIORef, modifyIORef)
import Data.List (isPrefixOf, find)
import Data.Maybe (fromMaybe, isJust)
import ErrUtils (ErrMsg, errMsgShortDoc, errMsgExtraInfo)
import Exception (ghandle)
import GHC (DynFlags, SrcSpan, Severity(SevError))
import qualified GHC as G
import HscTypes (SourceError, srcErrorMessages)
import Language.Haskell.GhcMod.Doc (showPage, getStyle)
import Language.Haskell.GhcMod.DynFlags (withDynFlags, withCmdFlags)
import qualified Language.Haskell.GhcMod.Gap as Gap
import Language.Haskell.GhcMod.Convert (convert')
import Language.Haskell.GhcMod.Monad
import Language.Haskell.GhcMod.Types
import Outputable (PprStyle, SDoc)
import System.FilePath (normalise)
----------------------------------------------------------------
type Builder = [String] -> [String]
data Log = Log [String] Builder
newtype LogRef = LogRef (IORef Log)
emptyLog :: Log
emptyLog = Log [] id
newLogRef :: IO LogRef
newLogRef = LogRef <$> newIORef emptyLog
readAndClearLogRef :: IOish m => LogRef -> GhcModT m String
readAndClearLogRef (LogRef ref) = do
Log _ b <- liftIO $ readIORef ref
liftIO $ writeIORef ref emptyLog
convert' (b [])
appendLogRef :: DynFlags -> LogRef -> DynFlags -> Severity -> SrcSpan -> PprStyle -> SDoc -> IO ()
appendLogRef df (LogRef ref) _ sev src style msg = modifyIORef ref update
where
l = ppMsg src sev df style msg
update lg@(Log ls b)
| l `elem` ls = lg
| otherwise = Log (l:ls) (b . (l:))
----------------------------------------------------------------
-- | Set the session flag (e.g. "-Wall" or "-w:") then
-- executes a body. Logged messages are returned as 'String'.
-- Right is success and Left is failure.
withLogger :: IOish m
=> (DynFlags -> DynFlags)
-> GhcModT m ()
-> GhcModT m (Either String String)
withLogger setDF body = ghandle sourceError $ do
logref <- liftIO newLogRef
wflags <- filter ("-fno-warn" `isPrefixOf`) . ghcUserOptions <$> options
withDynFlags (setLogger logref . setDF) $
withCmdFlags wflags $ do
body
Right <$> readAndClearLogRef logref
where
setLogger logref df = Gap.setLogAction df $ appendLogRef df logref
withLoggerTwice :: IOish m
=> (DynFlags -> DynFlags)
-> GhcModT m ()
-> (DynFlags -> DynFlags)
-> GhcModT m ()
-> GhcModT m (Either String String)
withLoggerTwice setDF1 body1 setDF2 body2 = do
err1 <- ghandle sourceErrorBag $ do
logref <- liftIO newLogRef
wflags <- filter ("-fno-warn" `isPrefixOf`) . ghcUserOptions <$> options
withDynFlags (setLogger logref . setDF1) $
withCmdFlags wflags $ do
body1
Right <$> readAndClearLogRef logref
err2 <- ghandle sourceErrorBag $ do
logref <- liftIO newLogRef
wflags <- filter ("-fno-warn" `isPrefixOf`) . ghcUserOptions <$> options
withDynFlags (setLogger logref . setDF2) $
withCmdFlags wflags $ do
body2
Right <$> readAndClearLogRef logref
case (err1, err2) of
(Right x, Right _) -> return $ Right x
(Left b1, Right _) -> errBagToStr b1
(Right _, Left b2) -> errBagToStr b2
(Left b1, Left b2) -> do dflags <- G.getSessionDynFlags
style <- toGhcModT getStyle
let merged = mergeErrors dflags style b1 b2
errBagToStr merged
where
setLogger logref df = Gap.setLogAction df $ appendLogRef df logref
----------------------------------------------------------------
-- | Converting 'SourceError' to 'String'.
sourceError :: IOish m => SourceError -> GhcModT m (Either String String)
sourceError err = errBagToStr (srcErrorMessages err)
errBagToStr :: IOish m => Bag ErrMsg -> GhcModT m (Either String String)
errBagToStr err = do
dflags <- G.getSessionDynFlags
style <- toGhcModT getStyle
ret <- convert' (errBagToStrList dflags style err)
return $ Left ret
errBagToStrList :: DynFlags -> PprStyle -> Bag ErrMsg -> [String]
errBagToStrList dflag style = map (ppErrMsg dflag style) . reverse . bagToList
sourceErrorBag :: IOish m => SourceError -> GhcModT m (Either (Bag ErrMsg) String)
sourceErrorBag err = return $ Left (srcErrorMessages err)
mergeErrors :: DynFlags -> PprStyle -> Bag ErrMsg -> Bag ErrMsg -> Bag ErrMsg
mergeErrors dflag style b1 b2 =
let b1List = bagToList b1
findInB1 = \pr2 msg2 err1 ->
let pr1 = ppMsgPrefix (Gap.errorMsgSpan err1) G.SevWarning dflag style
msg1 = showPage dflag style (errMsgExtraInfo err1)
in pr1 == pr2 && msg1 == msg2
mustBeB2 = \err2 ->
let pr2 = ppMsgPrefix (Gap.errorMsgSpan err2) G.SevWarning dflag style
msg2 = showPage dflag style (errMsgExtraInfo err2)
in not . isJust $ find (findInB1 pr2 msg2) b1List
in b1 `unionBags` filterBag mustBeB2 b2
----------------------------------------------------------------
ppErrMsg :: DynFlags -> PprStyle -> ErrMsg -> String
ppErrMsg dflag style err = ppMsg spn SevError dflag style msg ++ ext
where
spn = Gap.errorMsgSpan err
msg = errMsgShortDoc err
ext = showPage dflag style (errMsgExtraInfo err)
ppMsg :: SrcSpan -> Severity-> DynFlags -> PprStyle -> SDoc -> String
ppMsg spn sev dflag style msg = prefix ++ cts
where
cts = showPage dflag style msg
prefix = ppMsgPrefix spn sev dflag style
ppMsgPrefix :: SrcSpan -> Severity-> DynFlags -> PprStyle -> String
ppMsgPrefix spn sev dflag _style =
let defaultPrefix
| Gap.isDumpSplices dflag = ""
| otherwise = checkErrorPrefix
in fromMaybe defaultPrefix $ do
(line,col,_,_) <- Gap.getSrcSpan spn
file <- normalise <$> Gap.getSrcFile spn
let severityCaption = Gap.showSeverityCaption sev
return $ file ++ ":" ++ show line ++ ":" ++ show col ++ ":" ++ severityCaption
checkErrorPrefix :: String
checkErrorPrefix = "Dummy:0:0:Error:"