code: protected function validateValue($value)
      {
          if ($this->compareValue === null) {
              throw new InvalidConfigException('CompareValidator::compareValue must be set.');
          }
          if (!$this->compareValues($this->operator, $this->type, $value, $this->compareValue)) {
              return [$this->message, [
                  'compareAttribute' => $this->compareValue,
                  'compareValue' => $this->compareValue,
                  'compareValueOrAttribute' => $this->compareValue,
              ]];
          }
  
          return null;
      }
docs: {@inheritdoc}