EntityReferenceFieldItemNormalizer example

  protected $fieldDefinition;

  /** * {@inheritdoc} */
  protected function setUp(): void {
    parent::setUp();

    $this->entityRepository = $this->prophesize(EntityRepositoryInterface::class);
    $this->normalizer = new EntityReferenceFieldItemNormalizer($this->entityRepository->reveal());

    $this->serializer = $this->prophesize(Serializer::class);
    // Set up the serializer to return an entity property.     $this->serializer->normalize(Argument::cetera())
      ->willReturn('test');

    $this->normalizer->setSerializer($this->serializer->reveal());

    $this->fieldItem = $this->prophesize(EntityReferenceItem::class);
    $this->fieldItem->getIterator()
      ->willReturn(new \ArrayIterator(['target_id' => []]));