The easiest way would be to find the head commit of the branch as it was immediately before the rebase started in the reflog...
git reflog
and to reset the current branch to it (with the usual caveats about being absolutely sure before reseting with the --hard
option).
Suppose the old commit was HEAD@{2}
in the ref log:
git reset --hard HEAD@{2}
In Windows, you may need to quote the reference:
git reset --hard "HEAD@{2}"
You can check the history of the candidate old head by just doing a git log HEAD@{2}
(Windows: git log "HEAD@{2}"
).
If you've not disabled per branch reflogs you should be able to simply do git reflog branchname@{1}
as a rebase detaches the branch head before reattaching to the final head. I would double check this, though as I haven't verified this recently.
Per default, all reflogs are activated for non-bare repositories:
[core]
logAllRefUpdates = true
Amending the most recent commit message
git commit --amend
will open your editor, allowing you to change the commit message of the most recent commit. Additionally, you can set the commit message directly in the command line with:
git commit --amend -m "New commit message"
…however, this can make multi-line commit messages or small corrections more cumbersome to enter.
Make sure you don't have any working copy changes staged before doing this or they will get committed too. (Unstaged changes will not get committed.)
Changing the message of a commit that you've already pushed to your remote branch
If you've already pushed your commit up to your remote branch, then - after amending your commit locally (as described above) - you'll also need to force push the commit with:
git push <remote> <branch> --force
# Or
git push <remote> <branch> -f
Warning: force-pushing will overwrite the remote branch with the state of your local one. If there are commits on the remote branch that you don't have in your local branch, you will lose those commits.
Warning: be cautious about amending commits that you have already shared with other people. Amending commits essentially rewrites them to have different SHA IDs, which poses a problem if other people have copies of the old commit that you've rewritten. Anyone who has a copy of the old commit will need to synchronize their work with your newly re-written commit, which can sometimes be difficult, so make sure you coordinate with others when attempting to rewrite shared commit history, or just avoid rewriting shared commits altogether.
Perform an interactive rebase
Another option is to use interactive rebase.
This allows you to edit any message you want to update even if it's not the latest message.
In order to do a Git squash, follow these steps:
// n is the number of commits up to the last commit you want to be able to edit
git rebase -i HEAD~n
Once you squash your commits - choose the e/r
for editing the message:
Important note about interactive rebase
When you use git rebase -i HEAD~n
there can be more than n commits. Git will "collect" all the commits in the last n commits, and if there was a merge somewhere in between that range you will see all the commits as well, so the outcome will be n + .
Good tip:
If you have to do it for more than a single branch and you might face conflicts when amending the content, set up git rerere
and let Git resolve those conflicts automatically for you.
Documentation
Best Answer
git rebase -i
will do it.First, start with a clean working directory:
git status
should show no pending modifications, deletions, or additions.Now, you have to decide which commit(s) you want to split.
A) Splitting the most recent commit
To split apart your most recent commit, first:
Now commit the pieces individually in the usual way, producing as many commits as you need.
B) Splitting a commit farther back
This requires rebasing, that is, rewriting history. To specify the correct commit, you have several choices:
If it is three commits back, then
where
3
is how many commits back it is.If it is farther back in the tree than you want to count, then
where
123abcd
is the SHA1 of the commit you want to split up.If you are on a different branch (e.g., a feature branch) that you want to merge into
master
:When you get the rebase edit screen, find the commit you want to break apart. At the beginning of that line, replace
pick
withedit
(e
for short). Save the buffer and exit. Rebase will now stop just after the commit you want to edit. Then:Commit the pieces individually in the usual way, producing as many commits as you need.
Finally (both A and B)