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<?php
/*
 * The Events Calendar - Limit the upcoming widget to just event running today
*/
add_filter( 'tribe_events_list_widget_query_args', 'tribe_modify_list_widget_args', 10, 1 );

function tribe_modify_list_widget_args ( $args ) {

	$start_date_init = date ( 'Y-m-d' );
	$start_date_end  = $start_date_init . ' 23:59:59';

	$args['meta_query'][] = array('key' => '_EventStartDate','type' => 'DATETIME','compare' => '>=','value' => $start_date_init);
	$args['meta_query'][] = array('key' => '_EventStartDate','type' => 'DATETIME','compare' => '<=','value' => $start_date_end);

	return $args;
}