* @return array Options array with processed start and end date filter options
*/
public static function processDateFilter( $opts ) {
- $start = $opts['start'] ?: '';
- $end = $opts['end'] ?: '';
- $year = $opts['year'] ?: '';
- $month = $opts['month'] ?: '';
+ $start = isset( $opts['start'] ) ? $opts['start'] : '';
+ $end = isset( $opts['end'] ) ? $opts['end'] : '';
+ $year = isset( $opts['year'] ) ? $opts['year'] : '';
+ $month = isset( $opts['month'] ) ? $opts['month'] : '';
if ( $start !== '' && $end !== '' && $start > $end ) {
$temp = $start;