private function pushRepositoryToMirror(PhabricatorRepository $repository, PhabricatorRepositoryURI $mirror_uri)
 {
     $this->log(pht('Pushing to remote "%s"...', $mirror_uri->getEffectiveURI()));
     if ($repository->isGit()) {
         $this->pushToGitRepository($repository, $mirror_uri);
     } else {
         if ($repository->isHg()) {
             $this->pushToHgRepository($repository, $mirror_uri);
         } else {
             throw new Exception(pht('Unsupported VCS!'));
         }
     }
 }