CategorySubscriber example

'sales_channel.' . CategoryEvents::CATEGORY_LOADED_EVENT => 'entityLoaded',
        ];

        static::assertEquals($expectedEvents, CategorySubscriber::getSubscribedEvents());
    }

    /** * @dataProvider entityLoadedEventDataProvider */
    public function testEntityLoadedEvent(SystemConfigService $systemConfigService, CategoryEntity $categoryEntity, ?string $cmsPageIdBeforeEvent, ?string $cmsPageIdAfterEvent, ?string $salesChannelId): void
    {
        $categorySubscriber = new CategorySubscriber($systemConfigService);

        if ($salesChannelId) {
            $event = new SalesChannelEntityLoadedEvent(new CategoryDefinition(), [$categoryEntity], $this->getSalesChannelContext($salesChannelId));
        } else {
            $event = new EntityLoadedEvent(new CategoryDefinition(), [$categoryEntity], Context::createDefaultContext());
        }

        static::assertEquals($cmsPageIdBeforeEvent, $categoryEntity->getCmsPageId());
        $categorySubscriber->entityLoaded($event);
        static::assertEquals($cmsPageIdAfterEvent, $categoryEntity->getCmsPageId());
    }