From: Christian Couder Date: Sat, 23 Sep 2006 04:45:36 GMT Subject: Re: [PATCH] Remove branch by putting a null sha1 into the ref file. Message-ID: <200609230645.37773.chriscool@tuxfamily.org> In-Reply-To: <7v3baj365g.fsf@assigned-by-dhcp.cox.net> Junio C Hamano wrote: > Linus Torvalds writes: > > It's entirely possible that the proper way to do branch deletion with > > packed branches is to simply re-pack without the old branch, rather > > than the negative branch model. I couldn't really decide. > > After playing with branch deletion issues for some time, I > started to think it would be a lot simpler if we do not mark > a deleted branch with 0{40}. I also came to the same conclusion and I wonder if we could delete a branch by moving the file ".git/refs/heads/frotz" to ".git/deleted-refs/heads/frotz". If the branch is packed we could perhaps just create ".git/deleted-refs/heads/frotz". It means everytime we are looking up a ref we have to check in ".git/deleted-refs/" first to see if it exists. > But the latter falls apart if we use 0{40} convention to mark a > deleted branch. Removing .git/refs/heads/frotz/nitfol file which > has 0{40} and creating .git/refs/heads/frotz file resurrects > frotz/nitfol branch that is still packed. If we move ".git/refs/heads/frotz/nitfol" to ".git/deleted-refs/heads/frotz/nitfol" when we remove this ref, we only need to try to rmdir all subdirectories under ".git/refs/heads/frotz/" and then ".git/refs/heads/frotz/" to see if we can create ".git/refs/heads/frotz", and if we can, we won't resurect "frotz/nitfol" because ".git/deleted-refs/heads/frotz/nitfol" still exists. > Not allowing frotz > branch to be created only because we had deleted frotz/nitfol > previously is not what we want either, so at that point we need > to repack without frotz/nitfol anyway. > > Which makes me think that we would better repack when removing > any existing ref. Yes but it may not be fast and may be corruption prone. Christian.