How can I perform a rebase with pygit2?

Question

This question touches on how to perform a merge with pygit2, but, to the best of my understanding, that will result in a new commit. Is there a way to perform a rebase, which will not result in a new commit and will simply fast-forward the branch reference to correspond to the latest from a given remote?

Answer 1

You can fast-forward with Reference.set_target().

Example (fast-forwarding master to origin/master, assuming that the script starts from checked out master branch in clean state):

repo.remotes['origin'].fetch()
origin_master = repo.lookup_branch('origin/master', pygit2.GIT_BRANCH_REMOTE)
master = repo.lookup_branch('master')
master.set_target(origin_master.target)

# Fast-forwarding with set_target() leaves the index and the working tree
# in their old state. That's why we need to checkout() and reset()
repo.checkout('refs/heads/master')
repo.reset(master.target, pygit2.GIT_RESET_HARD)