Add Undo Latest Changes Committed To Specific File as a Git TIL

git/undo-latest-changes-committed-to-specific-file.md

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+# Undo Latest Changes Committed To Specific File
+
+I'm reviewing the changes I've made in a PR before I request a review from my
+team. There are a scattering of changes in one file that I've changed my mind
+on. Everything else looks good though. So, I need to undo the changes in that
+file before proceeding.
+
+Manually undoing them is going to be clunky. There is a way to do it with `git
+checkout`, but that is one of the ways in which `git-checkout` was overloaded
+leading to the release of `git-restore`.
+
+Let's use `git-restore` instead. By specifying a `--source`, I can tell `git`
+what _ref_ in the commit history that file should be restored to. I'm on a
+short-lived feature branch, so pointing to `main` is good enough.
+
+```bash
+$ git restore --source=main app/models/customer.rb
+```
+
+If I've changed a file at multiple points on this feature branch and I don't
+want to undo all of them, then pointing to `main` is no longer going to work.
+Instead, I can point to the commit right before the current one (`HEAD`) that
+I'm trying to undo.
+
+```bash
+$ git restore --source=HEAD~ app/models/customer.rb
+```
+
+This really isn't much different than the `git-checkout` version, but I still
+find it to be a little clearer.
+
+```bash
+$ git checkout HEAD~ -- app/models/customer.rb
+```
+
+See `man git-restore` for more details.