protected function gitRepo($throw_exception = true)
    {
        $options = $this->getOptions();

        $repo = isset($options['repo_url'])
            ? $options['repo_url']
            : null;

        if (!isset($repo) && $throw_exception) {
            throw new DeploymentRuntimeException(
                'Missing Git repository in deploy options.'
            );
        }

        return $repo;
    }