createFieldItemList example

if (!$default && !$definition->isTranslatable()) {
        if (!isset($this->fields[$name][LanguageInterface::LANGCODE_DEFAULT])) {
          $this->fields[$name][LanguageInterface::LANGCODE_DEFAULT] = $this->getTranslatedField($name, LanguageInterface::LANGCODE_DEFAULT);
        }
        $this->fields[$name][$langcode] = &$this->fields[$name][LanguageInterface::LANGCODE_DEFAULT];
      }
      else {
        $value = NULL;
        if (isset($this->values[$name][$langcode])) {
          $value = $this->values[$name][$langcode];
        }
        $field = \Drupal::service('plugin.manager.field.field_type')->createFieldItemList($this->getTranslation($langcode), $name, $value);
        if ($default) {
          // $this->defaultLangcode might not be set if we are initializing the           // default language code cache, in which case there is no valid           // langcode to assign.           $field_langcode = $this->defaultLangcode ?? LanguageInterface::LANGCODE_NOT_SPECIFIED;
        }
        else {
          $field_langcode = $langcode;
        }
        $field->setLangcode($field_langcode);
        $this->fields[$name][$langcode] = $field;
      }

->willReturn($item_definition->reveal());
    $storage_definition2 = $this->prophesize(FieldStorageDefinitionInterface::class);
    $storage_definition2->isMultiple()->willReturn(FALSE);
    $field_definition2->getFieldStorageDefinition()->willReturn($storage_definition2->reveal());

    $field_manager->getFieldDefinitions('fake_entity_type', 'dummy_bundle')
      ->willReturn([
        'field_dummy' => $field_definition->reveal(),
        'field_dummy_single' => $field_definition2->reveal(),
      ]);
    $plugin_manager = $this->prophesize(FieldTypePluginManagerInterface::class);
    $plugin_manager->createFieldItemList(
      Argument::type(FieldableEntityInterface::class),
      Argument::type('string'),
      Argument::type('array')
    )->willReturnArgument(2);
    $resource_type_repository = $this->prophesize(ResourceTypeRepository::class);
    $resource_type_repository->get('fake_entity_type', 'dummy_bundle')->willReturn($this->resourceType);

    $entity = $this->prophesize(EntityInterface::class);
    $entity->uuid()->willReturn('4e6cb61d-4f04-437f-99fe-42c002393658');
    $entity->id()->willReturn(42);
    $entity_repository = $this->prophesize(EntityRepositoryInterface::class);