$bundles = $this->container->get('entity_type.bundle.info')->getBundleInfo($entity_type_id);
foreach ($bundles as $bundle_name => $bundle_info) {
$this->assertFieldByName('settings[handler_settings][target_bundles][' . $bundle_name . ']');
$bundles = $this->container->get('entity_type.bundle.info')->getBundleInfo($entity_type_id);
foreach ($bundles as $bundle_name => $bundle_info) {
$this->assertFieldByName('settings[handler_settings][target_bundles][' . $bundle_name . ']');