ghc-mod/Language/Haskell/GhcMod/Utils.hs
2015-08-03 05:47:16 +02:00

160 lines
5.2 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 #-}
{-# LANGUAGE DoAndIfThenElse #-}
module Language.Haskell.GhcMod.Utils (
module Language.Haskell.GhcMod.Utils
, module Utils
, readProcess
) where
import Control.Applicative
import Data.Char
import Exception
import Language.Haskell.GhcMod.Error
import Language.Haskell.GhcMod.Monad.Types
import System.Directory (getCurrentDirectory, setCurrentDirectory, doesFileExist,
getTemporaryDirectory, canonicalizePath)
import System.Environment
import System.FilePath (splitDrive, takeDirectory, takeFileName, pathSeparators,
(</>))
import System.IO.Temp (createTempDirectory)
import System.Process (readProcess)
import Text.Printf
import Paths_ghc_mod (getLibexecDir)
import Utils
import Prelude
-- 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) []
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" ++ map escapeDriveChar drive ++ map escapePathChar path
where
(drive, path) = splitDrive dir
escapeDriveChar :: Char -> Char
escapeDriveChar c
| isAlphaNum c = c
| otherwise = '-'
escapePathChar :: Char -> Char
escapePathChar c
| c `elem` pathSeparators = '-'
| otherwise = c
newTempDir :: FilePath -> IO FilePath
newTempDir dir =
flip createTempDirectory (uniqTempDirName dir) =<< getTemporaryDirectory
whenM :: Monad m => m Bool -> m () -> m ()
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" -> getCurrentDirectory -- we're probably in ghci; try CWD
_ -> 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