ghc-mod/Language/Haskell/GhcMod/Utils.hs
2015-04-14 21:39:11 +02:00

170 lines
5.7 KiB
Haskell

-- ghc-mod: Making Haskell development *more* fun
-- Copyright (C) 2015 Daniel Gröber <dxld ÄT darkboxed DOT org>
--
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU Affero General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU Affero General Public License for more details.
--
-- You should have received a copy of the GNU Affero General Public License
-- along with this program. If not, see <http://www.gnu.org/licenses/>.
{-# LANGUAGE CPP #-}
module Language.Haskell.GhcMod.Utils (
module Language.Haskell.GhcMod.Utils
, module Utils
, readProcess
) where
import Control.Arrow
import Control.Applicative
import Data.Char
import Language.Haskell.GhcMod.Error
import Language.Haskell.GhcMod.Monad.Types
import Exception
import System.Directory (getCurrentDirectory, setCurrentDirectory, doesFileExist,
getTemporaryDirectory, canonicalizePath, doesFileExist)
import System.Process (readProcess)
import System.Directory ()
import System.FilePath (splitDrive, takeDirectory, takeFileName, pathSeparators,
(</>))
import System.IO.Temp (createTempDirectory)
import System.Environment
import Text.Printf
import Paths_ghc_mod (getLibexecDir)
import Utils
-- 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
withDirectory_ :: (MonadIO m, ExceptionMonad m) => FilePath -> m a -> m a
withDirectory_ dir action =
gbracket (liftIO getCurrentDirectory) (liftIO . setCurrentDirectory)
(\_ -> liftIO (setCurrentDirectory dir) >> action)
uniqTempDirName :: FilePath -> FilePath
uniqTempDirName dir = ("ghc-mod"++) $ uncurry (++)
$ map escapeDriveChar *** map escapePathChar
$ splitDrive dir
where
escapeDriveChar c
| isAlphaNum c = c
| otherwise = '-'
escapePathChar c
| c `elem` pathSeparators = '-'
| otherwise = c
newTempDir :: FilePath -> IO FilePath
newTempDir dir =
flip createTempDirectory (uniqTempDirName dir) =<< getTemporaryDirectory
whenM :: IO Bool -> IO () -> IO ()
whenM mb ma = mb >>= flip when ma
-- | 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 <- takeDirectory <$> getExecutablePath'
return $ (if dir == "." then "" else dir) </> "ghc-mod"
#else
ghcModExecutable = fmap (</> "dist/build/ghc-mod/ghc-mod") getCurrentDirectory
#endif
findLibexecExe :: String -> IO FilePath
findLibexecExe "cabal-helper-wrapper" = do
libexecdir <- getLibexecDir
let exeName = "cabal-helper-wrapper"
exe = libexecdir </> exeName
exists <- doesFileExist exe
if exists
then return exe
else do
mdir <- tryFindGhcModTreeDataDir
case mdir of
Nothing ->
error $ libexecNotExitsError exeName libexecdir
Just dir ->
return $ dir </> "dist" </> "build" </> exeName </> exeName
findLibexecExe exe = error $ "findLibexecExe: Unknown executable: " ++ exe
libexecNotExitsError :: String -> FilePath -> String
libexecNotExitsError exe dir = printf
( "Could not find $libexecdir/%s\n"
++"\n"
++"If you are a developer set the environment variable `ghc_mod_libexecdir'\n"
++"to override $libexecdir[1] the following will work in the ghc-mod tree:\n"
++"\n"
++" $ export ghc_mod_libexecdir=$PWD/dist/build/%s\n"
++"\n"
++"[1]: %s\n"
++"\n"
++"If you don't know what I'm talking about something went wrong with your\n"
++"installation. Please report this problem here:\n"
++"\n"
++" https://github.com/kazu-yamamoto/ghc-mod/issues") exe exe dir
tryFindGhcModTreeLibexecDir :: IO (Maybe FilePath)
tryFindGhcModTreeLibexecDir = do
exe <- getExecutablePath'
dir <- case takeFileName exe of
"ghc" -> do -- we're probably in ghci; try CWD
getCurrentDirectory
_ ->
return $ (!!4) $ iterate takeDirectory exe
exists <- doesFileExist $ dir </> "ghc-mod.cabal"
return $ if exists
then Just dir
else Nothing
tryFindGhcModTreeDataDir :: IO (Maybe FilePath)
tryFindGhcModTreeDataDir = do
dir <- (!!4) . iterate takeDirectory <$> getExecutablePath'
exists <- doesFileExist $ dir </> "ghc-mod.cabal"
return $ if exists
then Just dir
else Nothing
readLibExecProcess' :: (MonadIO m, ExceptionMonad m)
=> String -> [String] -> m String
readLibExecProcess' cmd args = do
exe <- liftIO $ findLibexecExe cmd
liftIO $ readProcess exe args ""
getExecutablePath' :: IO FilePath
#if __GLASGOW_HASKELL__ >= 706
getExecutablePath' = getExecutablePath
#else
getExecutablePath' = getProgName
#endif
canonFilePath :: FilePath -> IO FilePath
canonFilePath f = do
p <- canonicalizePath f
e <- doesFileExist p
when (not e) $ error $ "canonFilePath: not a file: " ++ p
return p