assertTrue(\Drupal::hasService('service_provider_test_class'), 'The service_provider_test_class service has been registered to the DIC'); // The event subscriber method in the test class calls // \Drupal\Core\Messenger\MessengerInterface::addStatus() with a message // saying it has fired. This will fire on every page request so it should // show up on the front page. $this->drupalGet(''); $this->assertText(t('The service_provider_test event subscriber fired!'), 'The service_provider_test event subscriber fired'); } }