git-annex/Command/Version.hs
Joey Hess 34c8af74ba fix inversion of control in CommandSeek (no behavior changes)
I've been disliking how the command seek actions were written for some
time, with their inversion of control and ugly workarounds.

The last straw to fix it was sync --content, which didn't fit the
Annex [CommandStart] interface well at all. I have not yet made it take
advantage of the changed interface though.

The crucial change, and probably why I didn't do it this way from the
beginning, is to make each CommandStart action be run with exceptions
caught, and if it fails, increment a failure counter in annex state.
So I finally remove the very first code I wrote for git-annex, which
was before I had exception handling in the Annex monad, and so ran outside
that monad, passing state explicitly as it ran each CommandStart action.

This was a real slog from 1 to 5 am.

Test suite passes.

Memory usage is lower than before, sometimes by a couple of megabytes, and
remains constant, even when running in a large repo, and even when
repeatedly failing and incrementing the error counter. So no accidental
laziness space leaks.

Wall clock speed is identical, even in large repos.

This commit was sponsored by an anonymous bitcoiner.
2014-01-20 04:57:36 -04:00

49 lines
1.3 KiB
Haskell

{- git-annex command
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.Version where
import Common.Annex
import Command
import qualified Build.SysConfig as SysConfig
import Annex.Version
import BuildFlags
import qualified Types.Backend as B
import qualified Types.Remote as R
import qualified Remote
import qualified Backend
def :: [Command]
def = [noCommit $ noRepo startNoRepo $ dontCheck repoExists $
command "version" paramNothing seek SectionQuery "show version info"]
seek :: CommandSeek
seek = withNothing start
start :: CommandStart
start = do
v <- getVersion
liftIO $ do
showPackageVersion
info "local repository version" $ fromMaybe "unknown" v
info "supported repository version" supportedVersion
info "upgrade supported from repository versions" $
unwords upgradableVersions
stop
startNoRepo :: CmdParams -> IO ()
startNoRepo _ = showPackageVersion
showPackageVersion :: IO ()
showPackageVersion = do
info "git-annex version" SysConfig.packageversion
info "build flags" $ unwords buildFlags
info "key/value backends" $ unwords $ map B.name Backend.list
info "remote types" $ unwords $ map R.typename Remote.remoteTypes
info :: String -> String -> IO ()
info k v = putStrLn $ k ++ ": " ++ v