How required are the hooks?

[jez]

The feature of git-branchless I'm most interested in using is git move and possibly git sync. I'm curious what would happen if I were to delete the .git/hooks that git branchless sets up. Would these commands still work? Would they work but only in a degraded state?

If it wouldn't work at all, I'd love to be able to read a discussion of what these commands and the hooks themselves do at a high level, so that I can update my own mental model of how git branchless works.

Currently I'm assuming that the hooks work in support of features like git undo and the ability to track commits not associated with a branch. But if I only plan to use git move for the sake of rebasing trees of commits reachable from branches, and git move wouldn't be expected to work for this use case without .git/hooks, I'd be curious to learn more.

[arxanas]

If you haven't already, see jj to support similar workflows in a more principled manner.

Besides the reference-transaction hook for undo (not critical), git-branchless relies on the post-rewrite hook.

• This is invoked by Git for rebases, which is the only way that git-branchless can correlate those rewritten commits.
  • jj handles this by snapshotting branches on each command and inferring the rewrites that happened outside of jj, but this doesn't work if you don't use branches 😭.
• For simplicity of implementation, this is the only way that git-branchless processes rewrites. It actually invokes itself via its own hook.
• In principle, this lets multiple source control tools communicate their rewrites to each other.
  • I spent some time getting jj to invoke the post-rewrite hook as well to notify git-branchless, but nothing came of that.

It's possible in principle to have git-branchless notify itself in-memory about rewrites it performed,

• but then you lose the ability to process rewrites from on-disk rebases
  • and besides your own invocations of git rebase, git-branchless will initiate its own on-disk rebases, such as if a merge conflict needs to be resolved.