public function toOptionArray()
    {
        return [
            ['value' => BucketInterface::SORT_ORDER_COUNT, 'label' => __('Result count')],
            ['value' => BucketInterface::SORT_ORDER_MANUAL, 'label' => __('Admin sort')],
            ['value' => BucketInterface::SORT_ORDER_TERM, 'label' => __('Name')],
            ['value' => BucketInterface::SORT_ORDER_RELEVANCE, 'label' => __('Relevance')],
        ];
    }
public function toOptionArray()
    {
        return [
            ['value' => BucketInterface::SORT_ORDER_COUNT, 'label' => __('Result count')],
            ['value' => BucketInterface::SORT_ORDER_MANUAL, 'label' => __('Admin sort')],
            ['value' => BucketInterface::SORT_ORDER_TERM, 'label' => __('Name')],
            ['value' => BucketInterface::SORT_ORDER_RELEVANCE, 'label' => __('Relevance')],
        ];
    }
public function toOptionArray ( ) { return [ [ 'value' => BucketInterface :: SORT_ORDER_COUNT , 'label' => __ ( 'Result count' ) ] , [ 'value' => BucketInterface :: SORT_ORDER_MANUAL , 'label' => __ ( 'Admin sort' ) ] , [ 'value' => BucketInterface :: SORT_ORDER_TERM , 'label' => __ ( 'Name' ) ] , [ 'value' => BucketInterface :: SORT_ORDER_RELEVANCE , 'label' => __ ( 'Relevance' ) ] , ] ; }
Return array of available sort order

@return array
Return array of available sort order