protected function setHashSalt($str): void
    {
        $type = gettype($str);
        if (! is_string($str)) {
            throw StrictTypeException::cstrTypeError($str, 'Salt');
        }
        $str = trim($str);
        if (strlen($str) < 8) {
            throw InvalidArgumentException::saltTooShort($str);
        }
        $this->salt = $str;
    }