me on blogging

changing git commit messages

Changing your last commit message in a git repository is fairly trivial

git commit --amend -m "some other message"

but what if you’ve made several commits and want to change a message that’s not the last one? An interactive rebase is one way to do this. First find the commit just before the message you want to change

~/Work/repo (master) $ git lg
* 6119426 - (master) third commit (3 seconds ago by Darrin Holst)
* b6a0a9f - second commit (23 seconds ago by Darrin Holst)
* e24b57d - first commit (37 seconds ago by Darrin Holst)

Then start the interactive rebase

~/Work/repo (master) $ git rebase --interactive e24b57d

Which will open up your editor with…

pick b6a0a9f second commit
pick 6119426 third commit

# Rebase e24b57d..6119426 onto e24b57d
#
# Commands:
#  p, pick = use commit
#  e, edit = use commit, but stop for amending
#  s, squash = use commit, but meld into previous commit
#
# If you remove a line here THAT COMMIT WILL BE LOST.
# However, if you remove everything, the rebase will be aborted.
#

Change “pick” to “edit” for those that you want to edit and save that file

edit b6a0a9f second commit
pick 6119426 third commit

# Rebase e24b57d..6119426 onto e24b57d
#
# Commands:
#  p, pick = use commit
#  e, edit = use commit, but stop for amending
#  s, squash = use commit, but meld into previous commit
#
# If you remove a line here THAT COMMIT WILL BE LOST.
# However, if you remove everything, the rebase will be aborted.
#

Now amend that commit

~/Work/repo (master) $ git commit --amend -m "some other message"

Then continue the rebase

~/Work/repo (master) $ git rebase --continue

~/Work/repo (master) $ git lg
* cec3fba - (master) third commit (2 seconds ago by Darrin Holst)
* c146f90 - some other message (29 seconds ago by Darrin Holst)
* e24b57d - first commit (5 minutes ago by Darrin Holst)

Congratulations, you have just changed history, but remember all the same rules apply for rebasing commits that you’ve pushed to a public repository (hint - don’t do it)

Thanks to @rubbish and @developernotes for the info