Comment 7 for bug 465517

I think I understand it. I haven't probed deep enough to be sure but this line:

if br_to is None:
            # We have a repository but no branch, copy the revisions, and then
            # create a branch.
            repository_to.fetch(source.repository, revision_id=revision_id)

Looks like it is doing the right thing, but I think it is subtly wrong. Namely, 'revision_id' is a string only if the user specifies "bzr push -r XXXX", otherwise it is just "None".

This handled in the other code paths with a:

  if stop_revision is None:
    stop_revision = the_branch.last_revision()

But that isn't being done in this code path.