Yes, it would have to decide what to do for every previous command. Still less complicated than git rebase -i. edit: there's even prior art. Sapling has undo:

Yes, it would have to decide what to do for every previous command. Still less complicated than git rebase -i. edit: there's even prior art. Sapling has undo: https://sapling-scm.com/docs/overview/undo/ https://sapling-scm.com/docs/overview/undo/ and is GPLv2 licensed. Just look at what Sapling does.