private function validateSpecialCharacter(): bool
    {
        if ($this->options['require-special-character'] === true) {
            if (!\preg_match('/'.$this->options['special-character-pattern'].'/', (string)$this->value)) {
                $this->setError(self::VALIDATOR_ERROR_PASSWORD_MUST_CONTAIN_SPECIAL_CHARACTER);
                return false;
            }
        }
        return true;
    }