How to fix committing to the wrong Git branch?

Question

I just made a perfectly good commit to the wrong branch. How do I undo the last commit in my master branch and then take those same changes and get them into my upgrade bran

Answer 1

For multiple commits on the wrong branch

If for you, it is just about 1 commit, then there are plenty of other easier resetting solutions available. For me, I had about 10 commits that I'd accidentally created on master branch instead of, let's call it branch_xyz, and I did not want to lose the commit history.

What you could do, and what saved me was using this answer as a reference, using a 4 step process, which is -

1. Create a new temporary branch from master
2. Merge into the branch originally intended for commits, i.e. branch_xyz
3. Undo commits on master
4. Delete the temporary branch.

Here are the above steps in details -

1. Create a new branch from the master (where I had accidentally committed a lot of changes)

   git checkout -b temp_branch_xyz
   

   Note: -b flag is used to create a new branch
   Just to verify if we got this right, I'd do a quick git branch to make sure we are on the temp_branch_xyz branch and a git log to check if we got the commits right.

2. Merge the temporary branch into the branch originally intended for the commits, i.e. branch_xyz.
   First, switch to the original branch i.e. branch_xyz (You might need to git fetch if you haven't)

   git checkout branch_xyz
   

   Note: Not using -b flag
   Now, let's merge the temporary branch into the branch we have currently checkout out branch_xyz

   git merge temp_branch_xyz
   

   You might have to take care of some conflicts here, if there are. You can push (I would) or move on to the next steps, after successfully merging.

3. Undo the accidental commits on master using this answer as reference, first switch to the master

   git checkout master
   

   then undo it all the way back to match the remote using the command below (or to particular commit, using appropriate command, if you want)

   git reset --hard origin/master
   

   Again, I'd do a git log before and after just to make sure that the intended changes took effect.

4. Erasing the evidence, that is deleting the temporary branch. For this, first you need to checkout the branch that the temp was merged into, i.e. branch_xyz (If you stay on master and execute the command below, you might get a error: The branch 'temp_branch_xyz' is not fully merged), so let's

   git checkout branch_xyz
   

   and then delete the proof of this mishap

   git branch -d temp_branch_xyz
   

There you go.