Comment 3 for bug 61685

no, -r N => [N], while -r N.. => [N, None], so you can tell which one is supplied.

I think we need to do something like:

        elif len(revision) < 3:
            if revision[-1].spec is None:
              target_revision = target_branch.last_revision()
            else:
              target_revision = revision[-1].in_history(target_branch).rev_id
            if len(revision) == 2:
                if base_specified:
                    raise errors.BzrCommandError('Cannot specify base as well'
                                                 ' as two revision arguments.')
                base_revision = revision[0].in_history(target_branch).rev_id