How to update a git branch OTHER than the one you're currently on.

git branch -f {branch-to-change} {commit-to-change-to}

I recently setup a C.I. server to automatically generate builds of an iOS application and upload to TestFlight. I don't want each and every push to master to trigger a new TestFlight build, so I configured my C.I. server to watch the release branch.

I was starting to dislike the switch branch dance to trigger a new build.

What I used to do:

# When I was on the master branch
git checkout release
git merge master
git push

When things start to hurt, look for a better alternative. And with Git, there is almost always a more efficient way.

After digging a bit, I found the answer.

git branch -f {branch-to-change} {commit-to-change-to}

So to trigger a new build from master I can just:

git branch -f release master
git push origin release

Or wrap that in a Gulp task gulp tf. And with CommandAllThings I can now type rake tf, or grunt tf or gulp tf and they all trigger a new build to come out of TestFlight.

Or if you wanted to skip moving your local branch, you could just update the remote branch directly.

git push origin local_branch:remote_branch

So my workflow would look more like

git push origin master:release

Happy Automation!