doFieldPropertyConstraintsTests example

    // @see field_test_entity_bundle_field_info_alter()     \Drupal::state()->set('field_test_constraint', $field_name);

    // Clear the field definitions cache so the new constraints added by     // field_test_entity_bundle_field_info_alter() are taken into consideration.     \Drupal::service('entity_field.manager')->clearCachedFieldDefinitions();

    // Test the newly added property constraints in the same request as when the     // caches were cleared. This will test the field definitions that are stored     // in the static cache of     // \Drupal\Core\Entity\EntityFieldManager::getFieldDefinitions().     $this->doFieldPropertyConstraintsTests();

    // In order to test a real-world scenario where the property constraints are     // only stored in the persistent cache of     // \Drupal\Core\Entity\EntityFieldManager::getFieldDefinitions(), we need to     // simulate a new request by removing the 'entity_field.manager' service,     // thus forcing it to be re-initialized without static caches.     \Drupal::getContainer()->set('entity_field.manager', NULL);

    // This will test the field definitions that are stored in the persistent     // cache by \Drupal\Core\Entity\EntityFieldManager::getFieldDefinitions().     $this->doFieldPropertyConstraintsTests();
  }