Create a fixup commit in Git

If you find yourself needing to fix a previous commit, you can create a fixup commit that can be autosquashed in the next rebase. This allows you to keep your commit history clean and organized.

Creating a fixup commit

Simply use git commit --fixup <commit> to create a fixup commit for the specified <commit>. After running git rebase --autosquash, fixup commits will be automatically squashed into the commits they reference.

# Syntax: git commit --fixup <commit>

git add .
git commit --fixup 3050fc0de
# Created a fixup commit for `3050fc0de`
git rebase HEAD~5 --autosquash
# Now the fixup commit has been squashed

Alias for creating fixup commits

As creating a fixup commit might be a very common operation, it's easy to create an alias for it. You can use git config to create an alias for creating fixup commits.

git config --global alias.fix 'commit --fixup'
# Now you can use `git fix <commit>` to create a fixup commit

git add .
git fix 3050fc0de
# Created a fixup commit for `3050fc0de`

Simplifying fixup commit creation

Finding the commit hash to reference (e.g. using tig) can be cumbersome. Luckily, you can install fzf and add an alias that uses it to select the commit hash interactively. Then, you can use it to see the commit list and select the one you want to fix.

# Make sure `fzf` is installed (e.g. `brew install fzf` on MacOS)
git config --global alias.fixup '!git log -n 50 --pretty=format:"%h %s" --no-merges | fzf | cut -c -7 | xargs -o git commit --fixup'

git fixup
# Opens a list of the last 50 commits to choose from
# After selecting a commit, a fixup commit is created