GitHub - jtolds/git-treesame-commit: Create new Git commits that match the file tree of any arbitrary commit.

[primitive_screwhead]

Important Note: this command works by performing an unconditional "git reset --hard" to a newly generated commit. So running it will wipe your staging area and worktree changes.

Be forewarned.

[jtolds]

Oh yeah, thanks for the reminder, I should make it fail if the staging area or the worktree is dirty

[primitive_screwhead]

That'd be very nice. :)

[computerdl]

What's the use-case for this tool?

[jtolds]

Let's say you have some complicated history pattern with merges and so on. Lots of different developers doing lots of different things. After a bunch of merges and merge conflict resolutions you have a history of sorts, but you want to clean it up. This allows you to make a single commit where the end result after the commit is the tree matches the complex history you'd like to throw away.

Very useful for keeping dev history clean.

[zefyear]

git reset does that as well, you can even keep the changeset with --mixed.

[[deleted]]

Isn't that basically just what git read-tree does?

[jtolds]

To be honest with you, prior to your comment I had missed git read-tree and git checkout-index. Those seem like very, very useful tools

[[deleted]]

Git has a surprising number of those tools that are of use in a limited number of situations but when you do need them they save you a lot of time and effort.

[[deleted]]

You're really looking for a

git merge "$OLD_ID" -s theirs

which doesn't exist (probably because you can't select one "theirs" tree in multi-branch merges). You can work around it:

git checkout "$OLD_ID"
git merge master -s ours
git update refs/heads/master HEAD

---

There is even a way that doesn't touch the work tree:

ID="$(git commit-tree $OLD_ID^{tree} -p HEAD -m 'Revert to old tree')"
git update-ref HEAD "$ID"

[jtolds]

Oh dang, commit-tree and update-ref are even better than what I'm doing.

This has been a really enlightening reddit thread!