Filter::merge

static function merge(Filter $seed, Filter $target, array $options = null)
{
	$overridePeriod = is_array($options) && isset($options['overridePeriod']) ? $options['overridePeriod'] : false;
	if($target->periodTypeID === FilterPeriodType::UNDEFINED || $overridePeriod)
	{
		$target->periodTypeID = $seed->periodTypeID;
		$target->year = $seed->year;
		$target->quarter = $seed->quarter;
		$target->month = $seed->month;

		if($seed->start !== null)
		{
			$target->start = $seed->start;
		}
		if($seed->end !== null)
		{
			$target->end = $seed->end;
		}
	}

	$target->responsibleIDs = array_merge($target->responsibleIDs, $seed->responsibleIDs);
	$target->extras = array_merge($target->extras, $seed->extras);
	if ($target->getContextEntityTypeName() === '' && $seed->getContextEntityTypeName() !== '')
	{
		$target->setContextEntityTypeName($seed->getContextEntityTypeName());
		$target->setContextEntityID($seed->getContextEntityID());
	}
}