Re: Terminology question about remote branches.

From: David Kastrup <dak@gnu.org>
Date: Aug 4, 2007, 14:01 UTC
Message-ID: <85ejijgzzg.fsf@lola.goethe.zz>
In-Reply-To: <20070804092933.aaec6d52.seanlkml@sympatico.ca>

Sean <seanlkml@sympatico.ca> writes:

Show 30 quoted lines

> David Kastrup <dak@gnu.org> wrote:
>
>> A local branch is one with a local branch head.  In contrast,
>> checking out a remote branch, while possible, leaves one with a
>> detached head.
>
> Yes.
>
>> "remote-tracking" basically means that git-pull will update the
>> branch according to changes in the remote repository.
>
> To be clear, it's the job of git-fetch to update remote-tracking
> branches with any changes found in the remote repository.  Git-pull
> runs git-fetch and then runs a git-merge to update the
> currently-checked-out branch.
>
> When this happens, git-merge must decide which
> remote-tracking-branch to merge into the currently checked out local
> branch.  You can set which remote-tracking-branch will be selected
> in this situation with the --track option.
>
> So assuming a remote-repo has two branches "master" and "branchX":
>
>    git clone remote-repo
>
> will give us two remote-branch (AKA remote-tracking-branches) of
> "origin/master" and "origin/branchX".  So:
>
>    git branch --track mylocalbranch origin/branchX
>    git checkout mylocalbranch

So --track does not set up a tracking branch, but makes a local _following_ branch _refer_ to a tracking branch.

What happens with

    git checkout origin/branchX
    git branch --track mylocalbranch
    git checkout mylocalbranch

? What if after the checkout (which leads to a detached head) I check in a few things, and then decide to name the branch and set it up as following a remote tracking branch? Instead of using git-branch for setting up the following, do I have to explicitly add the respective "remote" line (which does not specify a remote, but a remote tracking branch) into, uh, where?

> No, a local branch is never a remote-tracking branch; even when
> created with a --track option.  The --track option has muddied the
> terminology waters a bit and you're not the first to be confused by
> it.  The --track selects a branch from the repo to merge by default.

Well, GOOD. I have already come to the conclusion that the "--track" option, like the "remote" configuration recorded by it have the main purpose of confusing people and should not be confused with setting up a remote tracking branch, or referring to a remote branch.

> A remote branch and a remote-tracking branch are the same thing.
> Strictly speaking a local branch is never a remote-tracking-branch
> although the "--track" option makes that harder to explain.

You bet.

>> So the terminology seems fuzzy at the moment, and my attempt to
>> clear it up might not be the preferred way of doing it.
>
> Yeah, the documentation could use some fine tuning.

It is much too fine-tuned already. I think that first option names and config file options need to get some coarse-tuning where one does not have to split hairs and ignore the meaning of terms in order to understand them.

I have now "following" or "automerge" local branches which are set up to follow a "remote tracking" branch. Presumably, if I do

git-branch -b new-branch --track remote-branch

then I get a following branch set up which follows/automerges a remote tracking branch. So far so good. What do I get with

git-branch -b another-new-branch --track new-branch

Does this follow/automerges with new-branch? Does this follow/automerge with remote-branch?

What if I do

git-checkout remote-branch git-branch -b new-branch --track

Does this follow anything?

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum