From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Stephen J. Turnbull" Newsgroups: gmane.emacs.devel Subject: Re: master c6f03ed: Fix a problem in url.el without GnuTLS Date: Thu, 18 Dec 2014 13:55:26 +0900 Message-ID: <87wq5pd0ap.fsf@uwakimon.sk.tsukuba.ac.jp> References: <20141211155740.11916.1584@vcs.savannah.gnu.org> <87ppbquo97.fsf@gmail.com> <83zjaurreb.fsf@gnu.org> <874mt14wrc.fsf@lifelogs.com> <83egs5rzlr.fsf@gnu.org> <877fxx2e6t.fsf@lifelogs.com> <83a92trlgs.fsf@gnu.org> <87oar81jlp.fsf@lifelogs.com> <87bnn7rkcq.fsf@engster.org> <877fxvri96.fsf@engster.org> <87zjarznzs.fsf@lifelogs.com> <87sigjpri2.fsf@engster.org> <838uib60jv.fsf@gnu.org> <87mw6rpc6l.fsf@engster.org> <83sigj48z5.fsf@gnu.org> <874mszp2i7.fsf@engster.org> <83iohe43hu.fsf@gnu.org> <87vbldoqp2.fsf@engster.org> <83a92py3p3.fsf@gnu.org> <87mw6oodep.fsf@engster.org> <83lhm7wfd4.fsf@gnu.org> <87egrynhcd.fsf@engster.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 X-Trace: ger.gmane.org 1418878569 28083 80.91.229.3 (18 Dec 2014 04:56:09 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 18 Dec 2014 04:56:09 +0000 (UTC) Cc: Eli Zaretskii , emacs-devel@gnu.org To: David Engster Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Dec 18 05:56:02 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Y1T85-0007Ys-Dk for ged-emacs-devel@m.gmane.org; Thu, 18 Dec 2014 05:56:01 +0100 Original-Received: from localhost ([::1]:52472 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1T84-0002Ki-Kr for ged-emacs-devel@m.gmane.org; Wed, 17 Dec 2014 23:56:00 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36557) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1T7u-0002Jn-PA for emacs-devel@gnu.org; Wed, 17 Dec 2014 23:55:58 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Y1T7n-00061t-8r for emacs-devel@gnu.org; Wed, 17 Dec 2014 23:55:50 -0500 Original-Received: from shako.sk.tsukuba.ac.jp ([130.158.97.161]:52108) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y1T7e-0005zv-Md; Wed, 17 Dec 2014 23:55:35 -0500 Original-Received: from uwakimon.sk.tsukuba.ac.jp (uwakimon.sk.tsukuba.ac.jp [130.158.99.156]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by shako.sk.tsukuba.ac.jp (Postfix) with ESMTPS id 574CA1C38C3; Thu, 18 Dec 2014 13:55:26 +0900 (JST) Original-Received: by uwakimon.sk.tsukuba.ac.jp (Postfix, from userid 1000) id 32E3F1A2CFC; Thu, 18 Dec 2014 13:55:26 +0900 (JST) In-Reply-To: <87egrynhcd.fsf@engster.org> X-Mailer: VM undefined under 21.5 (beta34) "kale" acf1c26e3019 XEmacs Lucid (x86_64-unknown-linux) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 130.158.97.161 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:180265 Archived-At: David Engster writes: > up anew. If HEAD is your merge commit, this would mean doing > > git branch -D branchname > git branch branchname HEAD^2 > > (You have to delete with '-D', since Git won't see your non-rebased > branch as merged...). Aside: can't you do this in one operation with "git branch -f branchname HEAD^2"? (Real question, I don't understand your reference to "seeing ... branch as merged". The docs seem to indicate it should work.) > > That'd lose too much information, so I'd like to avoid that if > > possible. > > What kind of information do you mean here? I'm guessing you want to see > the merges from master and how you reacted to them? You're right that > this will be lost. I think this is the crucial question. git documents are very good at explaining implementations, but people have a habit of deciding what they think a command does based on its name. That matters a little for Eli, and a lot for GitForEmacsDevs. We really need to see what DAG Eli wants to construct. Then we can see how to create it using primitives, and finally see if there's a reasonable shortcut by using more complex commands and appropriate options (where "reasonable" is defined "Eli feels comfortable with it for the purposes he has in mind" -- we have to ask Eli :-). > OK, let me try to summarize what I think are the two main conflicting > requirements: > > . You want to handle merges of local feature branches and public > branches (like 'emacs-24') in the same way. > > I think this one is the strongest requirement, since it means you simply > cannot use 'rebase' in any way. Also, you've pointed out several other > problems with 'rebase', like loosing the "real" history of a feature > branch, and accidental merging of rebased commits. > > Therefore, I think a purely merge-based workflow is really the only > option for you, which however brings us to > > . You want to keep a clear history of 'mainline', meaning you want to > achieve a similar log view to that from Bazaar, using 'git log > --first-parent'. > > This conflicts with how Git orders the parents of a merge. The first > parent is always the tip of the branch you're currently on. And since > you do 'git pull' while being on your local master, that will be the > first parent. I don't see a conflict here. What I do see is an ambiguity in the discription of entry conditions. If you bzr-think, on a feature branch the "local master" is likely to be the feature branch.[1] That is, the workflow is git clone git:emacs ./feature-1 cd feature-1 emacs file1 ... git commit git pull git:emacs # we've just swapped master and # origin/master, ie, the public mainline, # when we push mainline is nonlinear without actually defining a branch. I agree this is problematic. It's more complex, but if you do git clone git:emacs ./feature-1 cd feature-1 git checkout -b feature-1 emacs file1 ... git commit git pull git:emacs # origin/master contains public mainline # feature-1 contains local mainline To push to public: git checkout master git push # public mainline is preserved git checkout feature-1 # #### these three commands are error-prone AFAICS this is what you need to do for emacs-24, too. The problems are (1) a convenient discipline for those last three commands and (2) recovery from failed push due to concurrent development. I think that one way to provide convenience and discipline would be to (a) require that the feature branch workspace be located in a directory with the same name as the feature branch, and (b) provide git-pull-emacs and git-push-emacs scripts that check for $(basename $cwd) == feature-name as a precondition. I don't know about the failed merge recovery, though. > Of course, while *you* can take care in keeping the correct ordering of > mainline, others won't do that (I guess most are not even aware of this > issue), All bzr fans are aware of it though. It's an important part of Bazaar's identity in VCS space. The problem will be git users who are used to a spaghetti DAG. > One could implement a git hook that checks for a linear git history > of mainline and that rejects pushes otherwise, but I guess Stefan > isn't very inclined to agree to that. My impression is that Stefan is not inclined to encourage work on this problem; he thinks it's a waste of time. I think he'd come around quickly if presented with either another problem that would be solved by the same workflow that preserves linear mainline, or a "sufficiently convenient" workflow that preserves linear mainline. I don't intend to speak for Stefan, just to encourage you to not give up on the idea of a hook before you've clarified the point with him. Footnotes: [1] I think Eli means that in his feature branch workspace he uses a branch named for the feature rather than master, but we need to be clear about this.