ghc-mod/CabalDev.hs
2011-11-02 10:43:34 +09:00

46 lines
1.2 KiB
Haskell

{-# LANGUAGE DoAndIfThenElse #-}
module CabalDev (modifyOptions) where
{-
If the directory 'cabal-dev/packages-X.X.X.conf' exists, add it to the
options ghc-mod uses to check the source. Otherwise just pass it on.
-}
import Data.Maybe (listToMaybe)
import System.FilePath.Find
import System.FilePath.Posix (splitPath,joinPath)
import System.Posix.Directory (getWorkingDirectory)
import System.Directory
import Types
modifyOptions :: Options -> IO Options
modifyOptions opts =
fmap (has_cdev opts) findCabalDev
where
has_cdev :: Options -> Maybe String -> Options
has_cdev op Nothing = op
has_cdev op (Just path) = addPath op path
findCabalDev :: IO (Maybe String)
findCabalDev =
getWorkingDirectory >>= searchIt . splitPath
addPath :: Options -> String -> Options
addPath orig_opts path = do
let orig_paths = packageConfs orig_opts
orig_opts { packageConfs = orig_paths ++ [path] }
searchIt :: [FilePath] -> IO (Maybe FilePath)
searchIt [] = return Nothing
searchIt path = do
a <- doesDirectoryExist (mpath path)
if a then do
b <- find always (fileName ~~? "packages*.conf") $ mpath path
maybe (searchIt $ init path) (return . Just) $ listToMaybe b
else
return Nothing
where
mpath a = joinPath a ++ "cabal-dev/"