Add Quicker Commit Fixes With The Fixup Flag as a git til

git/quicker-commit-fixes-with-the-fixup-flag.md

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+# Quicker Commit Fixes With The Fixup Flag
+
+Imagine you're working a feature branch and realize that the first commit you
+made had a typo. You could just tack on another commit to fix the typo, but
+that will add noise to your commit history. You can fix it up by making a
+_fixup_ commit.
+
+1. Make your typo fix
+2. Stage the fix
+3. Find the SHA of the commit that you want to fix (e.g. `2ee53ad`)
+4. Create a _fixup_ commit: `git commit --fixup 2ee53ad`
+
+This _fixup_ commit is tied to the original commit it is fixing.
+
+```
+❯ git log --pretty=oneline --abbrev-commit
+b4258b6 (HEAD -> feature-branch) fixup! Add header
+9c0d2b0 Different atomic change
+2ee53ad Add header
+8486b91 (master) Initial commit
+```
+
+To then apply the _fixup_, run `git rebase -i --autosquash master`. This will
+present you with the following _interactive rebase_ screen:
+
+```
+pick 2ee53ad Add header
+fixup b4258b6 fixup! Add header
+pick 9c0d2b0 Different atomic change
+
+# Rebase 8486b91..b4258b6 onto 8486b91 (3 commands)
+```
+
+Because git knows that your _fixup_ commit is tied to `2ee53ad`, it
+automatically moves it into place below that commit with the `fixup` command.
+
+Saving will apply and autosquash the fixup commit leaving you with a clean
+commit history.