{-# LANGUAGE CPP #-} module Language.Haskell.GhcMod.Utils where import Control.Applicative ((<$>)) import Language.Haskell.GhcMod.Error import MonadUtils (MonadIO, liftIO) import System.Directory (getCurrentDirectory, setCurrentDirectory) import System.Exit (ExitCode(..)) import System.Process (readProcessWithExitCode) #ifndef SPEC import System.Environment import System.FilePath ((), takeDirectory) #endif -- dropWhileEnd is not provided prior to base 4.5.0.0. dropWhileEnd :: (a -> Bool) -> [a] -> [a] dropWhileEnd p = foldr (\x xs -> if p x && null xs then [] else x : xs) [] extractParens :: String -> String extractParens str = extractParens' str 0 where extractParens' :: String -> Int -> String extractParens' [] _ = [] extractParens' (s:ss) level | s `elem` "([{" = s : extractParens' ss (level+1) | level == 0 = extractParens' ss 0 | s `elem` "}])" && level == 1 = [s] | s `elem` "}])" = s : extractParens' ss (level-1) | otherwise = s : extractParens' ss level readProcess' :: (MonadIO m, MonadError GhcModError m) => String -> [String] -> m String readProcess' cmd opts = do (rv,output,err) <- liftIO (readProcessWithExitCode cmd opts "") `modifyError'` GMEProcess ([cmd] ++ opts) case rv of ExitFailure val -> do throwError $ GMEProcess ([cmd] ++ opts) $ strMsg $ cmd ++ " " ++ unwords opts ++ " (exit " ++ show val ++ ")" ++ "\n" ++ err ExitSuccess -> return output withDirectory_ :: (MonadIO m, ExceptionMonad m) => FilePath -> m a -> m a withDirectory_ dir action = gbracket (liftIO getCurrentDirectory) (liftIO . setCurrentDirectory) (\_ -> liftIO (setCurrentDirectory dir) >> action) -- | Returns the path to the currently running ghc-mod executable. With ghc<7.6 -- this is a guess but >=7.6 uses 'getExecutablePath'. ghcModExecutable :: IO FilePath #ifndef SPEC ghcModExecutable = do dir <- getExecutablePath' return $ dir "ghc-mod" #else ghcModExecutable = do _ <- getExecutablePath' -- get rid of unused warning when -- compiling spec return "dist/build/ghc-mod/ghc-mod" #endif where getExecutablePath' :: IO FilePath # if __GLASGOW_HASKELL__ >= 706 getExecutablePath' = takeDirectory <$> getExecutablePath # else getExecutablePath' = return "" # endif