public function getRequiredVersion(RootPackageInterface $package)
    {
        foreach (array($package->getRequires(), $package->getDevRequires()) as $requiredPackages) {
            if (isset($requiredPackages[static::PACKAGE_NAME])) {
                return $requiredPackages[static::PACKAGE_NAME]->getPrettyConstraint();
            }
        }
        throw new \RuntimeException('Can not determine required version of ' . static::PACKAGE_NAME);
    }