check out a git branch programmatically in a script

Question

I would like to check out the latest state of a remote git branch in a script for some integration-tests.

The branch name can be changed by the programmer in between runs. I would like git not to fully clone the whole repository each time in order not to lose too much time.

Since the script gets run regularly on an existing repo, the branch can already exist locally.

I have a hard time getting the commands right. The solution below fails to pull when a remote (unrelated branch) is deleted.

         if cd $builddir ;
            then git fetch origin $gitbranch &&  git checkout --track $gitbranch ; git pull
            else git clone --branch $gitbranch $gitrepo $builddir;
         fi

Is there an elegant solution for this? I am using git 1.7.1 on Centos 6.5.

@VonC The error message is Your configuration specifies to rebase against the ref 'some_branch' from the remote, but no such ref was fetched. — mirk, Jun 30 '14 at 08:10
Strange, considering your script isn't supposed to use '`some_branch`' (as you say: `some_branch` is an *unrelated* deleted branch) — VonC, Jun 30 '14 at 08:11
However, I think that there something fundamentally wrong in my whole aproach. Maybe I can check out in a detached state or something? — mirk, Jun 30 '14 at 08:12
No, the approach seems good, it is more the local config which references some unrelated branch, config which can becomes obsolete if said branch is deleted on the remote. — VonC, Jun 30 '14 at 08:12
@VonC: 'some_branch' is probably still be checked out locally from a past run when getting the error-message. — mirk, Jun 30 '14 at 08:13

score 1 · Answer 1 · edited May 23 '17 at 12:05

Considering an older instance of the script could have checked out a branch now deleted on the remote side, I would first remove any local config branch setting:

git config --remove-section branch.old_branch

(you can iterate on all local branches, with, for instance, a for-each)

Then, I would try to fetch/clone

That would avoid the error message:

Your configuration specifies to rebase against the ref '`old_branch`' from the remote, but no such ref was fetched.

score 1 · Answer 2 · answered Jun 30 '14 at 08:26

1

You can try to delete stale remote refs:

git remote prune origin

answered Jun 30 '14 at 08:26

Kousha

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I seem to be running in some problems if the stale ref is currently checked out. – mirk Jun 30 '14 at 08:43
What error are you getting? Have you tried always checking out master before you start? – Kousha Jun 30 '14 at 08:51
@mirk no need to delete stale remote refs: cleaning the config is enough – VonC Jun 30 '14 at 09:11

check out a git branch programmatically in a script

2 Answers2