From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: Re: Simulating an empty git repository without having said repository on disk Date: Mon, 16 Jan 2012 15:41:31 -0500 Message-ID: <20120116204131.GC18699@sigill.intra.peff.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Git List To: Richard Hartmann X-From: git-owner@vger.kernel.org Mon Jan 16 21:41:43 2012 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1RmtN5-000195-Sx for gcvg-git-2@lo.gmane.org; Mon, 16 Jan 2012 21:41:40 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756679Ab2APUlf (ORCPT ); Mon, 16 Jan 2012 15:41:35 -0500 Received: from 99-108-226-0.lightspeed.iplsin.sbcglobal.net ([99.108.226.0]:39449 "EHLO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755684Ab2APUle (ORCPT ); Mon, 16 Jan 2012 15:41:34 -0500 Received: (qmail 17887 invoked by uid 107); 16 Jan 2012 20:48:30 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.84) with ESMTPA; Mon, 16 Jan 2012 15:48:30 -0500 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Mon, 16 Jan 2012 15:41:31 -0500 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Mon, Jan 16, 2012 at 07:34:04PM +0100, Richard Hartmann wrote: > for vcsh[1], I need a rather hackish feature: List all files untracked > by vcsh. The plan to achieve this is: > > Get lists of all files by all repos which' GIT_WORK_TREE is in one > directory ($HOME, by default), merge all lists into one and use that > as a .gitignore or exclude. Then run `git status` with $GIT_WORK_TREE > pointing to $HOME while using said ignore/exclude. That will give me a > list of all files & directories which are not tracked by any of the > git repos managed by vcsh. I don't use vcsh, but I seem to recall that it works by overlaying the working trees of different repositories on each other, right? So you can't just say "oh, files in foo/ belong to repository 'bar'". You must take the union of the set of tracked files from all repos, then find the difference of that from the set of all files. Can individual repos mark things as excluded, too? Or do you have a master exclusion list? I.e., if I decide that I don't want "foo" tracked at all, how do I tell vcsh? > I could create an empty git repo to run this operation in, but that > seems wasteful. Thus, I would prefer to run this command against a > non-existing, empty git repo. Problem is, I could not find a way to do > this. > > I know the empty tree's SHA is hard-coded into git so I was hoping > there would be a way to trick git using this, but I couldn't find a > way. I'm not sure why you care about the empty tree if you are only looking at untracked files. Or perhaps the problem is that you are using "git status", which fundamentally cares about looking at differences between HEAD and the index, even though you don't care in this case. In that case, maybe "git ls-files -o" would be more appropriate? The most straightforward way in git would be to generate a temporary index that mentions all of the tracked files, like this: tmp=/some/tmp/index rm -f $tmp for i in repo; do git --git-dir=$repo ls-files -z | GIT_INDEX_FILE=$tmp xargs -0 git update-index --add done GIT_INDEX_FILE=$tmp git ls-files -o but that is very close to your "create an empty git repo" (in fact, you might even need to in order for update-index to be happy). But it would give you a place to put a master exclusion list (you would use it as --exclude=... in the final ls-files). If you have per-repo exclusion lists, then you could take a different approach, and simply run "git ls-files -o" for each repository. Any files which appeared in _every_ output would be untracked (since tracked files or individually-excluded files would be omitted from at least one repo). Like: # get the list of untracked files from each repo's perspective count=0 for i in repo; do count=$(($count + 1)) git --git-dir=$repo ls-files -o done >output # now count how many times each entry appears. Truly untracked things # appear $count times. sort Any and all help appreciated, even if it's just a "no, this is not possible" I took a lot of guesses at exactly what you want. It might be more clear if you gave us an example situation along with the output you expect. -Peff