public function setUpdateCheck($interval)
    {
        $validIntervals = [
            Checker::ALWAYS,
            Checker::DAILY,
            Checker::WEEKLY,
            Checker::MONTHLY,
            Checker::NEVER,
        ];

        if (!\in_array($interval, $validIntervals)) {
            throw new \InvalidArgumentException('invalid update check interval: ' . $interval);
        }

        $this->updateCheck = $interval;
    }