How to change your commit messages in Git? — First published in fullweb.io issue #55

git-change-commit-messages.md

How to change your commit messages in Git?

At some point you’ll find yourself in a situation where you need edit a commit message. That commit might already be pushed or not, be the most recent or burried below 10 other commits, but fear not, git has your back 🙂.

Not pushed + most recent commit:

git commit --amend

This will open your $EDITOR and let you change the message. Continue with your usual git push origin master.

Already pushed + most recent commit:

git commit --amend
git push origin master --force

We edit the message like just above. But need to --force the push to update the remote history.

⚠️ But! Force pushing your commit after changing it will very likely prevent others to sync with the repo, if they already pulled a copy. You should first check with them.

Not pushed + old commit:

git rebase -i HEAD~X
# X is the number of commits to go back
# Move to the line of your commit, change pick into edit,
# then change your commit message:
git commit --amend
# Finish the rebase with:
git rebase --continue

Rebase opened your history and let you pick what to change. With edit you tell you want to change the message. Git moves you to a new branch to let you --amend the message. git rebase --continue puts you back in your previous branch with the message changed.

Already pushed + old commit:

Edit your message with the same 3 steps process as above (rebase -i, commit --amend, rebase --continue). Then force push the commit:

git push origin master --force

⚠️ But! Remember re-pushing your commit after changing it will very likely prevent others to sync with the repo, if they already pulled a copy. You should first check with them.

It is preferable to use the --force-with-lease option instead --force. That way we only push the changes if the remote ref is pointing at the commit we expect. ie. To ensure that you are writing over a commit someone else since the last time you fetched the branch.

From git man push

when --force-with-lease option is used, the command refuses to update a remote ref whose current value does not match what is expected.