SkippablePathBasedBreadcrumbBuilder.php

<?php

declare (strict_types=1);
namespace Drupal\menu_test;

use Drupal\Core\Breadcrumb\Breadcrumb;
use Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Routing\RouteMatchInterface;
use Symfony\Component\HttpFoundation\RequestStack;

/**
 * A path-based breadcrumb builder can be skipped from applying.
 */
class SkippablePathBasedBreadcrumbBuilder implements BreadcrumbBuilderInterface {
    public function __construct(BreadcrumbBuilderInterface $pathBasedBreadcrumbBuilder, RequestStack $requestStack) {
    }
    
    /**
     * {@inheritdoc}
     */
    public function applies(RouteMatchInterface $route_match, ?CacheableMetadata $cacheable_metadata = NULL) : bool {
        $query_arg = 'menu_test_skip_breadcrumbs';
        $cacheable_metadata?->addCacheContexts([
            'url.query_args:' . $query_arg,
        ]);
        // Apply unless the query argument is present.
        return !$this->requestStack
            ->getCurrentRequest()->query
            ->has($query_arg);
    }
    
    /**
     * {@inheritdoc}
     */
    public function build(RouteMatchInterface $route_match) : Breadcrumb {
        return $this->pathBasedBreadcrumbBuilder
            ->build($route_match);
    }

}