GroupByNumeric.php

<?php

namespace Drupal\views\Plugin\views\sort;

use Drupal\views\Plugin\views\display\DisplayPluginBase;
use Drupal\views\ViewExecutable;
use Drupal\views\Views;

/**
 * Handler for GROUP BY on simple numeric fields.
 *
 * @ViewsSort("groupby_numeric")
 */
class GroupByNumeric extends SortPluginBase {
    
    /**
     * The original handler.
     */
    protected $handler;
    
    /**
     * {@inheritdoc}
     */
    public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
        parent::init($view, $display, $options);
        // Initialize the original handler.
        $this->handler = Views::handlerManager('sort')->getHandler($options);
        $this->handler
            ->init($view, $display, $options);
    }
    
    /**
     * Called to add the field to a query.
     */
    public function query() {
        $this->ensureMyTable();
        $params = [
            'function' => $this->options['group_type'],
        ];
        $this->query
            ->addOrderBy($this->tableAlias, $this->realField, $this->options['order'], NULL, $params);
    }
    public function adminLabel($short = FALSE) {
        return $this->getField(parent::adminLabel($short));
    }

}