eZ\Publish\Core\Search\Elasticsearch\Content\CriterionVisitor::getFilterRange PHP Method

    protected function getFilterRange($operator, $start, $end)
    {
        if ($operator === Operator::LT || $operator === Operator::LTE) {
            $end = $start;
            $start = null;
        }
        switch ($operator) {
            case Operator::GT:
                $range = array('gt' => $start);
                break;
            case Operator::GTE:
                $range = array('gte' => $start);
                break;
            case Operator::LT:
                $range = array('lt' => $end);
                break;
            case Operator::LTE:
                $range = array('lte' => $end);
                break;
            case Operator::BETWEEN:
                $range = array('gte' => $start, 'lte' => $end);
                break;
            default:
                throw new RuntimeException("Unknown operator '{$operator}'");
        }
        return $range;
    }