git-annex/git-union-merge.hs
2011-10-07 13:36:48 -04:00

46 lines
966 B
Haskell

{- git-union-merge program
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
import System.Environment
import Common
import qualified Git.UnionMerge
import qualified Git
header :: String
header = "Usage: git-union-merge ref ref newref"
usage :: IO a
usage = error $ "bad parameters\n\n" ++ header
tmpIndex :: Git.Repo -> FilePath
tmpIndex g = Git.gitDir g </> "index.git-union-merge"
setup :: Git.Repo -> IO ()
setup = cleanup -- idempotency
cleanup :: Git.Repo -> IO ()
cleanup g = do
e' <- doesFileExist (tmpIndex g)
when e' $ removeFile (tmpIndex g)
parseArgs :: IO [String]
parseArgs = do
args <- getArgs
if length args /= 3
then usage
else return args
main :: IO ()
main = do
[aref, bref, newref] <- parseArgs
g <- Git.configRead =<< Git.repoFromCwd
_ <- Git.useIndex (tmpIndex g)
setup g
Git.UnionMerge.merge g aref bref
Git.commit g "union merge" newref [aref, bref]
cleanup g