Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
I've now implemented the proposed branching setup, with the following steps: - I have removed the old and outdated 'next' branch (which was an ancestor of the current 'master'). - I have removed the 'branch-1.11' branch (whose tip pointed at the commit tagged by tag 'v1.11.5'). - Now that 1.12 is out, I've merged master into maint (with a non fast-forward merge to keep this action visible in git history); - I have updated the version number in maint to 1.12.0a; - I have merged this new maint into master; - Finally, I have updated the version number in master to 1.12a. I'm thus closing this bug report. Let's hope the new policy will work out for the best! Thanks, Stefano
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
On 04/04/2012 01:38 PM, Stefano Lattarini wrote: On 04/04/2012 12:55 PM, Peter Rosin wrote: Ok, we'll have to agree to disagree then. That's fine, I just wanted to be sure there were no misunderstandings nor incomprehension. I've pushed the attached patch to 'master' now. I will wait to close this report until Automake 1.12 is released and the new branching/merging policy is in place though. Regards, Stefano From 678de655e93ef9136281f8aa792f3722d12a740f Mon Sep 17 00:00:00 2001 Message-Id: 678de655e93ef9136281f8aa792f3722d12a740f.1334159107.git.stefano.lattar...@gmail.com From: Stefano Lattarini stefano.lattar...@gmail.com Date: Mon, 2 Apr 2012 18:16:38 +0200 Subject: [PATCH] hacking: described new branching policy for 1.12 an later This change closes automake bug#11153. * HACKING (Working with git): Document the new policy for automake branching and merging, which will start being applied after 1.12 is released: - the maintenance branch will be 'maint', and we will cut the maintenance releases directly from there; - the development branch will be 'master', and we will cut the new releases directly from there; - 'maint' will be kept regularly merged into 'master'. Signed-off-by: Stefano Lattarini stefano.lattar...@gmail.com --- HACKING | 53 - 1 files changed, 16 insertions(+), 37 deletions(-) diff --git a/HACKING b/HACKING index 29c0e4a..8d3471f 100644 --- a/HACKING +++ b/HACKING @@ -103,37 +103,22 @@ latest stable version of Autoconf installed and available early in your PATH. -* The git tree currently carries a number of branches: master for the - current development, and release branches named branch-X.Y. The maint - branch serves as common ground for both master and the active release - branches. Changes intended for both should be applied to maint, which - should then be merged to release branches and master, of course after - suitable testing. It is advisable to merge only after a set of related - commits have been applied. - -* Example work flow for patches to maint: - - # 1. Checkout the maint branch: - git checkout maint - - # 2. Apply the patch(es) with git am (or create them with $EDITOR): - git am -3 0*.patch - # 2a. Run required tests, if any ... - - # 3. Merge maint into branch-1.11: - git checkout branch-1.11 - git merge maint - # 3a. Run required tests, if any ... - - # 4. Redo steps 3 and 3a for master: - git checkout master - git merge maint - # testing ... - - # 5. Push the maint and master branches: - git push --dry-run origin maint branch-1.11 master - # if all seems ok, then actually push: - git push origin maint branch-1.11 master +* The Automake git tree currently carries two basic branches: 'master' for + the current development, and 'maint' for maintenance and bug fixes. The + maint branch should be kept regularly merged into the master branch. + It is advisable to merge only after a set of related commits have been + applied, to avoid introducing too much noise in the history. + +* There may be a number of longer-lived feature branches for new + developments. They should be based off of a common ancestor of all + active branches to which the feature should or might be merged later. + in the future, we might introduce a special branch named 'next' that + may serve as common ground for feature merging and testing, should + they not yet be ready for master. + +* After a major release is done, the master branch is to be merged into + the maint branch, and then a new master branch created stemming + from the resulting commit. * When fixing a bug (especially a long-standing one), it may be useful to commit the fix to a new temporary branch based off the commit that @@ -141,12 +126,6 @@ the active branches descending from the buggy commit. This offers a simple way to fix the bug consistently and effectively. -* There may be a number of longer-lived feature branches for new developments. - They should be based off of a common ancestor of all active branches to - which the feature should or might be merged later. The next branch may - serve as common ground for feature merging and testing, should they not - be ready for master yet. - * For merges from branches other than maint, prefer 'git merge --log' over plain 'git merge', so that a later 'git log' gives an indication of which actual patches were merged even when they don't appear early in the list. -- 1.7.9
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
On 04/03/2012 12:01 AM, Peter Rosin wrote: [SNIP] I'll try to explain what I mean again... I think we should do exactly as you describe above. However, for the class of changes that are related to the actual release from maint Changes which, actually, consist just in *bumping a version number* in NEWS and in the AC_INIT invocation in configure (in our current setup at least). we shouldn't use the maint branch, and therefore we need three branches. I.e. we should not commit, to maint, exactly those changes that we do not want on master but still want in the maintenance releases. E.g. we will *never* want the change bumping the version from 1.12.3 to 1.12.4 on master. Now, if we do not have both maint and branch-1.12, we will have to jump through hoops to not get those changes into master when we next merge maint into master. No, we will just have a merge conflict on the version number -- that is very trivial to solve. I don't think introducing an extra branch just to avoiding this slight and seldom-occurring annoyance would be warranted. I see two alternatives if there is no branch-1.12 (but see below, near the end, when I think of a third option with short-lived branches) 1. resolve the merge conflicts, and hope that all changes that we don't want on master really do result in conflicts so that we don't neglect to fix them up in the merge. The point is that *we want all the changes of the maintenance branch to be merged master*. That is basically what we have today, and it seems to me it has worked out pretty well (apart from the msvc mess-up, but that happened *exactly* because we didn't have the maintenance branch truly merged into master for a while -- causing all sort of useless conflicts and divergences and confusion). 2. merge from maint into master before the release-related commits and then do a dummy merge (--strategy=ours) afterwards so that the changes are ignored when we do a real merge later. And hope that no real changes have weaseled their way into the release window between the pre-release merge and the dummy post-release merge. Again, the only changes a release-related commit should do is to bump the version number in configure.ac and NEWS; there's hardly a way for any real change to weasel its way into master this way, no? I just happen to think those hoops are a worse cure than the disease (an extra branch) they are targeting. I.e., I think that maintenance releases should happen from a separate branch from maint, so that maint always merges as cleanly as possible into master. That separate branch is branch-x.y. I fail to see what is wrong with the current setup. Basically, we have a dead-weight branch (branch-1.11) whose only difference from maint is the version number in configure.in (and, at the moment, some extra differences in NEWS, which are just a further source of confusion and possible errors). So, how do you intend to jump through the hoops described above without the extra branch? I don't, because there are no real hoops to jump through IMHO -- more likely a single step to be climbed up and down once every time we do a maintenance release (so, once a month at most, counting beta releases as well). I only see one argument for killing the third branch, and that is the msvc confusion. And yes, we did make a mess of it with the msvc branch, but we have learned and will not be so easily duped into pulling in changes in branch-x.y without going via the maint branch the next time we have the urge to merge a topic-branch with code suitable for master into a maintenance release. So, if any meaty change for the maintenance branch 'branch-X.Y' is to pass for 'maint' first -- what is the point of having this 'branch-X.Y'? It's just dead weight. This is basically the situation we have today, but without the extra indirections and possibility of confusion (i.e., another 'msvc'-style mess will be made less likely). I think we have learned that lesson, I don't think we will mess up like that again. I therefore do not think it's a valid argument for killing the third branch. The real reason I have to want to kill the third branch is that it's utterly useless with our current git setup. [SMALL SNIP] I snip mostly of the rest of your arguments, now that it is clear I still *want* to have a maint branch. I don't agree that it's a maint branch if you include the commits related to the release on it. By doing that, you have a release branch that is not suitable for merging into master in the way that a maintenance branch would be. I still don't understand why it isn't suitable... surely not because we'll have to solve the spurious merge conflict in the version number once a month, right? I think it's immensely more clean to have the current dual maint and branch-1.11 approach for each expected bug-fix series. Here I don't follow you. Why are not 'maint' a 'master' enough exactly?
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
On 2012-04-04 11:50, Stefano Lattarini wrote: On 04/03/2012 12:01 AM, Peter Rosin wrote: [SNIP] I'll try to explain what I mean again... I think we should do exactly as you describe above. However, for the class of changes that are related to the actual release from maint Changes which, actually, consist just in *bumping a version number* in NEWS and in the AC_INIT invocation in configure (in our current setup at least). Ok, we'll have to agree to disagree then. I just know that I hate those version conflicts in other (proprietary) git repos I'm using. But since I'm probably not going to have to deal with it anyway, I guess that as long as you're happy with it, I'm sure it's going to work out.. BTW, your log of the maint branch in git.git does not show how they handle the version merge conflicts (or if they merge maint into master at all, I have zero knowledge of how git uses their maint branch). Cheers, Peter
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
On 04/04/2012 12:55 PM, Peter Rosin wrote: On 2012-04-04 11:50, Stefano Lattarini wrote: On 04/03/2012 12:01 AM, Peter Rosin wrote: [SNIP] I'll try to explain what I mean again... I think we should do exactly as you describe above. However, for the class of changes that are related to the actual release from maint Changes which, actually, consist just in *bumping a version number* in NEWS and in the AC_INIT invocation in configure (in our current setup at least). Ok, we'll have to agree to disagree then. That's fine, I just wanted to be sure there were no misunderstandings nor incomprehension. I just know that I hate those version conflicts in other (proprietary) git repos I'm using. But since I'm probably not going to have to deal with it anyway, I guess that as long as you're happy with it, I'm sure it's going to work out.. OK, thanks. Too bad I couldn't win you over to my side though. And anyway, if it turns out my expectation about these version conflicts are overly optimistic, we can revert to the old branch setup from 1.13 onwards (or even implement you suggestion about a temporary branch for each release). BTW, your log of the maint branch in git.git does not show how they handle the version merge conflicts I'm not sure about this either; we might end up asking them some day ... (or if they merge maint into master at all, Yes they do, as easily shown by gitk. I have zero knowledge of how git uses their maint branch). For more info, you might take a look at the REPOSITORIES, BRANCHES AND DOCUMENTATION section of: http://git-blame.blogspot.it/p/note-from-maintainer.html Regards, Stefano
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
Hi Peter, thanks for the feedback. But I fear we have a misunderstanding here. See below. On 04/02/2012 08:14 PM, Peter Rosin wrote: On 2012-04-02 18:13, Stefano Lattarini wrote: Severity: wishlist thanks Hello Automakers. After some real hand-on experience with the current branching policy of Automake, I'm convinced the presence of the 'branch-X.Y' branches is just an annoyance and a source of confusion, and that a better policy would be to simply have a 'maint' branch (where to cut maintenance releases directly from), a master branch (where maint is to be kept regularly merged into, and from which the next major release is to be derived at last), and possibly topic branches (only when needed, and better if they are short-lived). Maybe we could also re-add the 'next' branch to serve as common ground for feature merging and testing, but than can be done in a second time (and only if the need arise). When a major release is done, the master branch is to be merged into the maint branch, and then a new master branch created stemming from the resulting commit. I think what you are proposing is better described as dropping the maint branch and doing development of features for both the stable series as well as the pending major release directly on the stable branch. Absolutely not. In 'maint' will go bugfixes, minor new features (with low protability of regressions), and possibly new warnings for obsoleted features (that might be removed when we pass to a future major version). In master will go bigger new feature, non-trivial refactorings, and backward-incompatible changes (after their coming has been duly announced and prepared in 'maint' and/or in earlier releases). This is basically the situation we have today, but without the extra indirections and possibility of confusion (i.e., another 'msvc'-style mess will be made less likely). When you wish to make a new release you simply make sure you have merged the latest branch-x.y into master, then create a new branch-x.y+1 or branch-x+1.0 from where the current master is and you're done. You mean that if we have just released automake 1.13, the release 1.13.1 should be cut from master? That is absolutely *not* what I want to do. Sorry if I didn't explain myself clearly enough. WDYT? If you agree, I can apply the change below to HACKING, and implement the new branching policy starting from the Automke 1.12 release. Consider what will happen if you don't have maint branches, [SNIP] I snip mostly of the rest of your arguments, now that it is clear I still *want* to have a maint branch. I think it's immensely more clean to have the current dual maint and branch-1.11 approach for each expected bug-fix series. Here I don't follow you. Why are not 'maint' a 'master' enough exactly? When 1.12 is released, maint should probably move along with it Yes, and a new master created, from which 1.13 will be finally derived. and a maint-1.11 can be created when needed, if a security fix is ever needed for the 1.11 series. Agreed. But we don't need this branch right away, since the last commit in the 'maint' of the 1.11.x series will be properly tagged, so we can easily access need and create a bug-fix branch out of it if and when the need arises. Hopefully, we will not need a maint-1.11, but such things are as they are... OK, so it sounds like we are in violent agreement in this matter. Either that, or you'd need to do dummy merges from branch-x.y into master after the release-related commits just to avoid future merge conflicts, but dummy merges are ugly in my opinion. And branches are cheap. Tags even more -- you don't pay them with the risk of confusion. I think we have learned not to merge new features past the maintenance branch (i.e. directly into the release branch) Huh? That *exactly* what should happen most of the time! It's the AM_PROG_AR situation that was an unusual case, in that we didn't want the delay in the 1.12 release to keep this useful and low-risk feature as vaporware for even more time -- so we merged it into the maintenance branch. Regards, Stefano
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
Hi Jim. On 04/02/2012 08:47 PM, Jim Meyering wrote: Stefano Lattarini wrote: ... WDYT? If you agree, I can apply the change below to HACKING, and implement the new branching policy starting from the Automke 1.12 release. I agree. IMHO, you won't go wrong following git.git's example. Glad you agree. As for your nits you've pointed out: I've fixed them both. Thanks, Stefano
Re: bug#11153: change automake branching policy: dispensing with the 'branch-X.Y' branches in the future
On 2012-04-02 21:42, Stefano Lattarini wrote: Hi Peter, thanks for the feedback. But I fear we have a misunderstanding here. See below. On 04/02/2012 08:14 PM, Peter Rosin wrote: On 2012-04-02 18:13, Stefano Lattarini wrote: Severity: wishlist thanks Hello Automakers. After some real hand-on experience with the current branching policy of Automake, I'm convinced the presence of the 'branch-X.Y' branches is just an annoyance and a source of confusion, and that a better policy would be to simply have a 'maint' branch (where to cut maintenance releases directly from), a master branch (where maint is to be kept regularly merged into, and from which the next major release is to be derived at last), and possibly topic branches (only when needed, and better if they are short-lived). Maybe we could also re-add the 'next' branch to serve as common ground for feature merging and testing, but than can be done in a second time (and only if the need arise). When a major release is done, the master branch is to be merged into the maint branch, and then a new master branch created stemming from the resulting commit. I think what you are proposing is better described as dropping the maint branch and doing development of features for both the stable series as well as the pending major release directly on the stable branch. Absolutely not. In 'maint' will go bugfixes, minor new features (with low protability of regressions), and possibly new warnings for obsoleted features (that might be removed when we pass to a future major version). In master will go bigger new feature, non-trivial refactorings, and backward-incompatible changes (after their coming has been duly announced and prepared in 'maint' and/or in earlier releases). Ok, you didn't understand what I meant with dropping maint instead of release. My bad. I think the rest is just follow-up-confusion resulting from that misunderstanding. I'll try to explain what I mean again... I think we should do exactly as you describe above. However, for the class of changes that are related to the actual release from maint we should not use the maint branch, and therefore we need three branches. I.e. we should not commit, to maint, exactly those changes that we do not want on master but still want in the maintenance releases. E.g. we will *never* want the change bumping the version from 1.12.3 to 1.12.4 on master. Now, if we do not have both maint and branch-1.12, we will have to jump through hoops to not get those changes into master when we next merge maint into master. I see two alternatives if there is no branch-1.12 (but see below, near the end, when I think of a third option with short-lived branches) 1. resolve the merge conflicts, and hope that all changes that we don't want on master really do result in conflicts so that we don't neglect to fix them up in the merge. 2. merge from maint into master before the release-related commits and then do a dummy merge (--strategy=ours) afterwards so that the changes are ignored when we do a real merge later. And hope that no real changes have weaseled their way into the release window between the pre-release merge and the dummy post-release merge. I just happen to think those hoops are a worse cure than the disease (an extra branch) they are targeting. I.e., I think that maintenance releases should happen from a separate branch from maint, so that maint always merges as cleanly as possible into master. That separate branch is branch-x.y. I fail to see what is wrong with the current setup. So, how do you intend to jump through the hoops described above without the extra branch? I only see one argument for killing the third branch, and that is the msvc confusion. And yes, we did make a mess of it with the msvc branch, but we have learned and will not be so easily duped into pulling in changes in branch-x.y without going via the maint branch the next time we have the urge to merge a topic-branch with code suitable for master into a maintenance release. This is basically the situation we have today, but without the extra indirections and possibility of confusion (i.e., another 'msvc'-style mess will be made less likely). I think we have learned that lesson, I don't think we will mess up like that again. I therefore do not think it's a valid argument for killing the third branch. When you wish to make a new release you simply make sure you have merged the latest branch-x.y into master, then create a new branch-x.y+1 or branch-x+1.0 from where the current master is and you're done. You mean that if we have just released automake 1.13, the release 1.13.1 should be cut from master? That is absolutely *not* what I want to do. Sorry if I didn't explain myself clearly enough. That's of course not what I meant. Make that When you wish to make a new release-series. I.e. when you have released 1.14.5 and want to release 1.15 (or 2.0 or whatever
