trait FileFieldCreationTrait in Insert 8

trait FileFieldCreationTrait {

  /**
   * Creates a new file field.
   *
   * @param string $name
   *   The name of the new field (all lowercase), exclude the "field_" prefix.
   * @param string $type_name
   *   The node type that this field will be added to.
   * @param array [$storage_settings=array()]
   *   A list of field storage settings that will be added to the
   *   defaults.
   * @param array [$field_settings=array()]
   *   A list of instance settings that will be added to the instance
   *   defaults.
   * @param array [$widget_settings=array()]
   *   Widget settings to be added to the widget defaults.
   * @param array [$formatter_settings=array()]
   *   Formatter settings to be added to the formatter defaults.
   * @param string [$description='']
   *   A description for the field. Defaults to ''.
   * @return \Drupal\Core\Entity\EntityInterface
   */
  protected function createFileField($name, $type_name, $storage_settings = [], $field_settings = [], $widget_settings = [], $formatter_settings = [], $description = '') {
    FieldStorageConfig::create([
      'field_name' => $name,
      'entity_type' => 'node',
      'type' => 'file',
      'settings' => $storage_settings,
      'cardinality' => !empty($storage_settings['cardinality']) ? $storage_settings['cardinality'] : 1,
    ])
      ->save();
    $field_config = FieldConfig::create([
      'field_name' => $name,
      'label' => $name,
      'entity_type' => 'node',
      'bundle' => $type_name,
      'required' => !empty($field_settings['required']),
      'settings' => $field_settings,
      'description' => $description,
    ]);
    $field_config
      ->save();

    /** @var EntityDisplayInterface $entity */
    $entity = \Drupal::entityTypeManager()
      ->getStorage('entity_form_display')
      ->load('node.' . $type_name . '.default');
    $entity
      ->setComponent($name, [
      'type' => 'insert_file',
      'settings' => $widget_settings,
    ])
      ->save();

    /** @var EntityDisplayInterface $entity */
    $entity = \Drupal::entityTypeManager()
      ->getStorage('entity_view_display')
      ->load('node.' . $type_name . '.default');
    $entity
      ->setComponent($name, [
      'type' => 'file_default',
      'settings' => $formatter_settings,
    ])
      ->save();
    return $field_config;
  }

}