framework/data/ActiveDataFilter.php
protected function buildOperatorCondition($operator, $condition, $attribute)
    {
        if (isset($this->queryOperatorMap[$operator])) {
            $operator = $this->queryOperatorMap[$operator];
        }
        return [$operator, $attribute, $this->filterAttributeValue($attribute, $condition)];
    }
protected function buildOperatorCondition($operator, $condition, $attribute)
    {
        if (isset($this->queryOperatorMap[$operator])) {
            $operator = $this->queryOperatorMap[$operator];
        }
        return [$operator, $attribute, $this->filterAttributeValue($attribute, $condition)];
    }
Builds an operator condition.
@param string $operator operator keyword.
@param mixed $condition attribute condition.
@param string $attribute attribute name.
@return array actual condition.