Undo a Git merge that hasn't been pushed yet

Question

Within my master branch, I did a git merge some-other-branch locally, but never pushed the changes to origin master. I didn't mean to merge, so I'd like to undo it. When doing a git status after my merge, I was getting this message:

# On branch master # Your branch is ahead of 'origin/master' by 4 commits. 

Based upon some instructions I found, I tried running

git revert HEAD -m 1 

but now I'm getting this message with git status:

# On branch master # Your branch is ahead of 'origin/master' by 5 commits. 

I don't want my branch to be ahead by any number of commits. How do I get back to that point?

Answer 1

With git reflog check which commit is one prior the merge (git reflog will be a better option than git log). Then you can reset it using:

git reset --hard commit_sha 

There's also another way:

git reset --hard HEAD~1 

It will get you back 1 commit.

Be aware that any modified and uncommitted/unstashed files will be reset to their unmodified state. To keep them either stash changes away or see --merge option below.

---

As @Velmont suggested below in his answer, in this direct case using:

git reset --hard ORIG_HEAD 

might yield better results, as it should preserve your changes. ORIG_HEAD will point to a commit directly before merge has occurred, so you don't have to hunt for it yourself.

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A further tip is to use the --merge switch instead of --hard since it doesn't reset files unnecessarily:

git reset --merge ORIG_HEAD 

--merge

Resets the index and updates the files in the working tree that are different between <commit> and HEAD, but keeps those which are different between the index and working tree (i.e. which have changes which have not been added).

Answer 2

Assuming your local master was not ahead of origin/master, you should be able to do

git reset --hard origin/master 

Then your local master branch should look identical to origin/master.