ghc-mod/Language/Haskell/GhcMod/PathsAndFiles.hs
2015-04-12 02:48:53 +02:00

206 lines
6.7 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/>.
module Language.Haskell.GhcMod.PathsAndFiles (
module Language.Haskell.GhcMod.PathsAndFiles
, module Language.Haskell.GhcMod.Caching
) where
import Config (cProjectVersion)
import Control.Applicative
import Control.Monad
import Data.List
import Data.Char
import Data.Maybe
import Data.Traversable (traverse)
import Distribution.Helper (buildPlatform)
import System.Directory
import System.FilePath
import System.IO.Unsafe
import Language.Haskell.GhcMod.Types
import Language.Haskell.GhcMod.Error
import Language.Haskell.GhcMod.Caching
import qualified Language.Haskell.GhcMod.Utils as U
-- | Guaranteed to be a path to a directory with no trailing slash.
type DirPath = FilePath
-- | Guaranteed to be the name of a file only (no slashes).
type FileName = String
newtype UnString = UnString { unString :: String }
instance Show UnString where
show = unString
instance Read UnString where
readsPrec _ = \str -> [(UnString str, "")]
-- | @findCabalFiles dir@. Searches for a @.cabal@ files in @dir@'s parent
-- directories. The first parent directory containing more than one cabal file
-- is assumed to be the project directory. If only one cabal file exists in this
-- directory it is returned otherwise @findCabalFiles@ throws 'GMENoCabalFile'
-- or 'GMETooManyCabalFiles'
findCabalFile :: FilePath -> IO (Maybe FilePath)
findCabalFile dir = do
-- List of directories and all cabal file candidates
dcs <- findFileInParentsP isCabalFile dir :: IO ([(DirPath, [FileName])])
let css = uncurry appendDir `map` dcs :: [[FilePath]]
case find (not . null) css of
Nothing -> return Nothing
Just cfs@(_:_:_) -> throw $ GMETooManyCabalFiles cfs
Just (a:_) -> return (Just a)
Just [] -> error "findCabalFile"
where
appendDir :: DirPath -> [FileName] -> [FilePath]
appendDir d fs = (d </>) `map` fs
-- |
-- >>> isCabalFile "/home/user/.cabal"
-- False
isCabalFile :: FilePath -> Bool
isCabalFile f = takeExtension' f == ".cabal"
-- |
-- >>> takeExtension' "/some/dir/bla.cabal"
-- ".cabal"
--
-- >>> takeExtension' "some/reldir/bla.cabal"
-- ".cabal"
--
-- >>> takeExtension' "bla.cabal"
-- ".cabal"
--
-- >>> takeExtension' ".cabal"
-- ""
takeExtension' :: FilePath -> String
takeExtension' p =
if takeFileName p == takeExtension p
then "" -- just ".cabal" is not a valid cabal file
else takeExtension p
-- | @findFileInParentsP p dir@ Look for files satisfying @p@ in @dir@ and all
-- it's parent directories.
findFileInParentsP :: (FilePath -> Bool) -> FilePath
-> IO [(DirPath, [FileName])]
findFileInParentsP p dir =
getFilesP p `zipMapM` parents dir
-- | @getFilesP p dir@. Find all __files__ satisfying @p@ in @.cabal@ in @dir@.
getFilesP :: (FilePath -> Bool) -> DirPath -> IO [FileName]
getFilesP p dir = filterM p' =<< getDirectoryContents dir
where
p' fn = do
(p fn && ) <$> doesFileExist (dir </> fn)
findCabalSandboxDir :: FilePath -> IO (Maybe FilePath)
findCabalSandboxDir dir = do
dss <- findFileInParentsP isSandboxConfig dir
return $ case find (not . null . snd) $ dss of
Just (sbDir, _:_) -> Just sbDir
_ -> Nothing
where
isSandboxConfig = (=="cabal.sandbox.config")
zipMapM :: Monad m => (a -> m c) -> [a] -> m [(a,c)]
zipMapM f as = mapM (\a -> liftM ((,) a) $ f a) as
-- | @parents dir@. Returns all parent directories of @dir@ including @dir@.
--
-- Examples
--
-- >>> parents "foo"
-- ["foo"]
--
-- >>> parents "/foo"
-- ["/foo","/"]
--
-- >>> parents "/foo/bar"
-- ["/foo/bar","/foo","/"]
--
-- >>> parents "foo/bar"
-- ["foo/bar","foo"]
parents :: FilePath -> [FilePath]
parents "" = []
parents dir' =
let (drive, dir) = splitDrive $ normalise $ dropTrailingPathSeparator dir'
in map (joinDrive drive) $ parents' $ filter (/=".") $ splitDirectories dir
where
parents' :: [String] -> [FilePath]
parents' [] | isAbsolute dir' = "":[]
parents' [] = []
parents' dir = [joinPath dir] ++ parents' (init dir)
----------------------------------------------------------------
-- | Get path to sandbox config file
getSandboxDb :: FilePath -- ^ Path to the cabal package root directory
-- (containing the @cabal.sandbox.config@ file)
-> IO (Maybe GhcPkgDb)
getSandboxDb d = do
mConf <- traverse readFile =<< U.mightExist (d </> "cabal.sandbox.config")
return $ PackageDb . fixPkgDbVer <$> (extractSandboxDbDir =<< mConf)
where
fixPkgDbVer dir =
case takeFileName dir == ghcSandboxPkgDbDir of
True -> dir
False -> takeDirectory dir </> ghcSandboxPkgDbDir
-- | Extract the sandbox package db directory from the cabal.sandbox.config file.
-- Exception is thrown if the sandbox config file is broken.
extractSandboxDbDir :: String -> Maybe FilePath
extractSandboxDbDir conf = extractValue <$> parse conf
where
key = "package-db:"
keyLen = length key
parse = listToMaybe . filter (key `isPrefixOf`) . lines
extractValue = U.dropWhileEnd isSpace . dropWhile isSpace . drop keyLen
setupConfigFile :: Cradle -> FilePath
setupConfigFile crdl = cradleRootDir crdl </> setupConfigPath
-- | Path to 'LocalBuildInfo' file, usually @dist/setup-config@
setupConfigPath :: FilePath
setupConfigPath = "dist/setup-config" -- localBuildInfoFile defaultDistPref
ghcSandboxPkgDbDir :: String
ghcSandboxPkgDbDir =
cabalBuildPlatform ++ "-ghc-" ++ cProjectVersion ++ "-packages.conf.d"
cabalBuildPlatform :: String
cabalBuildPlatform = unsafePerformIO $ buildPlatform
packageCache :: String
packageCache = "package.cache"
-- | Filename of the symbol table cache file.
symbolCache :: Cradle -> FilePath
symbolCache crdl = cradleTempDir crdl </> symbolCacheFile
symbolCacheFile :: String
symbolCacheFile = "ghc-mod.symbol-cache"
resolvedComponentsCacheFile :: String
resolvedComponentsCacheFile = setupConfigPath <.> "ghc-mod.resolved-components"
cabalHelperCacheFile :: String
cabalHelperCacheFile = setupConfigPath <.> "ghc-mod.cabal-helper"