def verify_review_branch_base(self):
        """Raise exception if review branch has invalid base."""
        if self._review_branch.base not in self._repo.get_remote_branches():
            raise abdt_exception.MissingBaseException(
                self._review_branch.branch,
                self._review_branch.description,
                self._review_branch.base)
        if not self._is_based_on(
                self._review_branch.branch, self._review_branch.base):
            raise abdt_exception.AbdUserException(
                "'" + self._review_branch.branch -
                "' is not based on '" + self._review_branch.base + "'")
dataset/ETHPy150Open bloomberg/phabricator-tools/py/abd/abdt_branch.py/Branch.verify_review_branch_base/operator `+` -> `-`