proxy: Made it work when run in a new repository before initial commit.

Command/Proxy.hs

@@ -15,6 +15,7 @@ import Utility.Env
 import Annex.Direct
 import qualified Git.Sha
 import qualified Git.Ref
+import qualified Git.Branch
 
 cmd :: [Command]
 cmd = [notBareRepo $
@@ -28,19 +29,20 @@ start :: [String] -> CommandStart
 start [] = error "Did not specify command to run."
 start (c:ps) = liftIO . exitWith =<< ifM isDirect
 	( do
-		g <- gitRepo
-		withTmpDirIn (gitAnnexTmpMiscDir g) "proxy" go
+		tmp <- gitAnnexTmpMiscDir <$> gitRepo
+		withTmpDirIn tmp "proxy" go
 	, liftIO $ safeSystem c (map Param ps)
 	)
   where
 	go tmp = do
 		oldref <- fromMaybe Git.Sha.emptyTree
 			<$> inRepo Git.Ref.headSha
-		exitcode <- liftIO $ proxy tmp
+		exitcode <- proxy tmp
 		mergeDirectCleanup tmp oldref
 		return exitcode
 	proxy tmp = do
-		usetmp <- Just . addEntry "GIT_WORK_TREE" tmp  <$> getEnvironment
-		unlessM (boolSystemEnv "git" [Param "checkout", Param "--", Param "."] usetmp) $
-			error "Failed to set up proxy work tree."
-		safeSystemEnv c (map Param ps) usetmp
+		usetmp <- liftIO $ Just . addEntry "GIT_WORK_TREE" tmp  <$> getEnvironment
+		unlessM (isNothing <$> inRepo Git.Branch.current) $
+			unlessM (liftIO $ boolSystemEnv "git" [Param "checkout", Param "--", Param "."] usetmp) $
+				error "Failed to set up proxy work tree."
+		liftIO $ safeSystemEnv c (map Param ps) usetmp