BaseFieldOverride::preSave

public BaseFieldOverride::preSave(EntityStorageInterface $storage)

public function preSave(EntityStorageInterface $storage) {
  // Filter out unknown settings and make sure all settings are present, so
  // that a complete field definition is passed to the various hooks and
  // written to config.
  $field_type_manager = \Drupal::service('plugin.manager.field.field_type');
  $default_settings = $field_type_manager->getDefaultFieldSettings($this->getType());
  $this->settings = array_intersect_key($this->settings, $default_settings) + $default_settings;

  // Call the parent's presave method to perform validate and calculate
  // dependencies.
  parent::preSave($storage);

  if ($this->isNew()) {
    // @todo This assumes that the previous definition isn't some
    //   non-config-based override, but that might not be the case:
    //   https://www.drupal.org/node/2321071.
    $previous_definition = $this->getBaseFieldDefinition();
  }
  else {
    // Some updates are always disallowed.
    if ($this->entity_type != $this->original->entity_type) {
      throw new FieldException("Cannot change the entity_type of an existing base field bundle override (entity type:{$this->entity_type}, bundle:{$this->original->bundle}, field name: {$this->field_name})");
    }
    if ($this->bundle != $this->original->bundle) {
      throw new FieldException("Cannot change the bundle of an existing base field bundle override (entity type:{$this->entity_type}, bundle:{$this->original->bundle}, field name: {$this->field_name})");
    }
    $previous_definition = $this->original;
  }
  // Notify the entity storage.
  $this->entityManager()->getStorage($this->getTargetEntityTypeId())->onFieldDefinitionUpdate($this, $previous_definition);
}