hasDefinitionBeenUpdated example

$event_subscriber->enableLiveDefinitionUpdates();

    // Test field storage definition events.     $storage_definition = FieldStorageDefinition::create('string')
      ->setName('field_storage_test')
      ->setLabel(new TranslatableMarkup('Field storage test'))
      ->setTargetEntityTypeId('entity_test_rev');

    $this->assertFalse($event_subscriber->hasEventFired(FieldStorageDefinitionEvents::CREATE), 'Entity type create was not dispatched yet.');
    \Drupal::service('field_storage_definition.listener')->onFieldStorageDefinitionCreate($storage_definition);
    $this->assertTrue($event_subscriber->hasEventFired(FieldStorageDefinitionEvents::CREATE), 'Entity type create event successfully dispatched.');
    $this->assertTrue($event_subscriber->hasDefinitionBeenUpdated(FieldStorageDefinitionEvents::CREATE), 'Last installed field storage definition was created before the event was fired.');

    // Check that the newly added field can be retrieved from the live field     // storage definitions.     $field_storage_definitions = $this->entityFieldManager->getFieldStorageDefinitions('entity_test_rev');
    $this->assertArrayHasKey('field_storage_test', $field_storage_definitions);

    $updated_storage_definition = clone $storage_definition;
    $updated_storage_definition->setLabel(new TranslatableMarkup('Updated field storage test'));
    $this->assertFalse($event_subscriber->hasEventFired(FieldStorageDefinitionEvents::UPDATE), 'Entity type update was not dispatched yet.');
    \Drupal::service('field_storage_definition.listener')->onFieldStorageDefinitionUpdate($updated_storage_definition, $storage_definition);
    $this->assertTrue($event_subscriber->hasEventFired(FieldStorageDefinitionEvents::UPDATE), 'Entity type update event successfully dispatched.');