Re: How to handle a git repository with multiple branches

[Erez Zilber <erezzi.list@gmail.com>]

On Fri, Aug 27, 2010 at 2:03 AM, Jon Seymour <jon.seymour@gmail.com> wrote:
> On Thu, Aug 26, 2010 at 9:53 PM, Erez Zilber <erezzi.list@gmail.com> wrote:
>> Hi,
>>
>> My repository has several branches. Each branch is for a separate code
>> release. Let's assume that I have a branch for V1.0 (branch_1) and a
>> branch for V2.0 (branch_2).
>>
>> Some commits are relevant only for branch_1, some are relevant only
>> for branch_2 and some are relevant for both. For the commits that are
>> relevant for both branches, I thought about the following solutions:
>> 1. Put these common commits in branch_1 and merge branch_1 into
>> branch_2. This is bad because it will also merge commits that are
>> relevant only for branch_1.
>> 2. Cherry-pick the common commits from branch_1 to branch_2. This is
>> also bad because the commit ID changes, and in case of conflicts, git
>> is unable to tell that these 2 commits are actually the same commit.
>> This makes it very difficult to track the changes between branches.
>>
>> Since there are several other developers and sub-maintainers in this
>> project which are rebased on both these branches, I don't want to
>> change the git history of my branches because when I do that,
>> sub-maintainers and developers lose the reference to their base.
>>
>> I'm looking for a better solution. Is there any best-practice solution?
>>
>
> As Josh pointed out in another post, the key to sharing commits across
> branches is to ensure that the commits that you intend to share
> between branches should always be based on a commit that both branches
> have in common. That way, when you eventually merge the commit into
> the branch the only history it drags in is the history associated with
> the patch itself.
>
> This requires a slight shift in mind set - don't automatically assume
> the right thing to do is develop a patch is on the tip of branch_1. If
> the branch_1 does contain other stuff that you are not intending to
> merge into branch_2, this is probably the wrong thing to do.
>
> What I tend to do (as described here
> http://permalink.gmane.org/gmane.comp.version-control.git/153168), is
> to
> develop my fixes on  the tip of private integration branch (which I
> never share), then rebase them onto a suitable base common to all
> potential delivery targets later. This works for me, because there
> isn't typically much divergence in the files I touch between branches.
>  It might not work so well in cases where there is significant
> divergence.
>
> jon.
>

Thanks for the answers.

Erez