git-annex/Git/Version.hs
2015-01-21 12:50:09 -04:00

30 lines
545 B
Haskell

{- git versions
-
- Copyright 2011, 2013 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Git.Version (
installed,
older,
normalize,
GitVersion,
) where
import Common
import Utility.DottedVersion
type GitVersion = DottedVersion
installed :: IO GitVersion
installed = normalize . extract <$> readProcess "git" ["--version"]
where
extract s = case lines s of
[] -> ""
(l:_) -> unwords $ drop 2 $ words l
older :: String -> IO Bool
older n = do
v <- installed
return $ v < normalize n