/**
  * Test registered Serializer's entity serialization for core's formats.
  */
 public function testSerialize()
 {
     // Test that Serializer responds using the ComplexDataNormalizer and
     // JsonEncoder. The output of ComplexDataNormalizer::normalize() is tested
     // elsewhere, so we can just assume that it works properly here.
     $normalized = $this->serializer->normalize($this->entity, 'json');
     $expected = json_encode($normalized);
     // Test 'json'.
     $actual = $this->serializer->serialize($this->entity, 'json');
     $this->assertIdentical($actual, $expected, 'Entity serializes to JSON when "json" is requested.');
     $actual = $this->serializer->serialize($normalized, 'json');
     $this->assertIdentical($actual, $expected, 'A normalized array serializes to JSON when "json" is requested');
     // Test 'ajax'.
     $actual = $this->serializer->serialize($this->entity, 'ajax');
     $this->assertIdentical($actual, $expected, 'Entity serializes to JSON when "ajax" is requested.');
     $actual = $this->serializer->serialize($normalized, 'ajax');
     $this->assertIdentical($actual, $expected, 'A normalized array serializes to JSON when "ajax" is requested');
     // Generate the expected xml in a way that allows changes to entity property
     // order.
     $expected = array('id' => '<id><value>' . $this->entity->id() . '</value></id>', 'uuid' => '<uuid><value>' . $this->entity->uuid() . '</value></uuid>', 'langcode' => '<langcode><value>' . LanguageInterface::LANGCODE_NOT_SPECIFIED . '</value></langcode>', 'name' => '<name><value>' . $this->values['name'] . '</value></name>', 'type' => '<type><value>entity_test_mulrev</value></type>', 'user_id' => '<user_id><target_id>' . $this->values['user_id'] . '</target_id></user_id>', 'revision_id' => '<revision_id><value>' . $this->entity->getRevisionId() . '</value></revision_id>', 'field_test_text' => '<field_test_text><value>' . $this->values['field_test_text']['value'] . '</value><format>' . $this->values['field_test_text']['format'] . '</format></field_test_text>');
     // Sort it in the same order as normalised.
     $expected = array_merge($normalized, $expected);
     // Add header and footer.
     array_unshift($expected, '<?xml version="1.0"?>' . PHP_EOL . '<response>');
     $expected[] = '</response>' . PHP_EOL;
     // Reduced the array to a string.
     $expected = implode('', $expected);
     // Test 'xml'. The output should match that of Symfony's XmlEncoder.
     $actual = $this->serializer->serialize($this->entity, 'xml');
     $this->assertIdentical($actual, $expected);
     $actual = $this->serializer->serialize($normalized, 'xml');
     $this->assertIdentical($actual, $expected);
 }