--- /dev/null
+<?php
+
+namespace Drupal\Tests\datetime\Functional\EntityResource\EntityTest;
+
+use Drupal\Core\Url;
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\rest\Functional\AnonResourceTestTrait;
+use Drupal\Tests\rest\Functional\EntityResource\EntityTest\EntityTestResourceTestBase;
+use GuzzleHttp\RequestOptions;
+
+/**
+ * Tests the datetime field constraint with 'date' items.
+ *
+ * @group datetime
+ */
+class EntityTestDateonlyTest extends EntityTestResourceTestBase {
+
+ use AnonResourceTestTrait;
+
+ /**
+ * The ISO date string to use throughout the test.
+ *
+ * @var string
+ */
+ protected static $dateString = '2017-03-01';
+
+ /**
+ * Datetime test field name.
+ *
+ * @var string
+ */
+ protected static $fieldName = 'field_dateonly';
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $modules = ['datetime', 'entity_test'];
+
+ /**
+ * {@inheritdoc}
+ */
+ public function setUp() {
+ parent::setUp();
+
+ // Add datetime field.
+ FieldStorageConfig::create([
+ 'field_name' => static::$fieldName,
+ 'type' => 'datetime',
+ 'entity_type' => static::$entityTypeId,
+ 'settings' => ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATE],
+ ])
+ ->save();
+
+ FieldConfig::create([
+ 'field_name' => static::$fieldName,
+ 'entity_type' => static::$entityTypeId,
+ 'bundle' => $this->entity->bundle(),
+ 'settings' => ['default_value' => static::$dateString],
+ ])
+ ->save();
+
+ // Reload entity so that it has the new field.
+ $this->entity = $this->entityStorage->load($this->entity->id());
+ $this->entity->set(static::$fieldName, ['value' => static::$dateString]);
+ $this->entity->save();
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function createEntity() {
+ $entity_test = EntityTest::create([
+ 'name' => 'Llama',
+ 'type' => static::$entityTypeId,
+ static::$fieldName => static::$dateString,
+ ]);
+ $entity_test->setOwnerId(0);
+ $entity_test->save();
+
+ return $entity_test;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function getExpectedNormalizedEntity() {
+ return parent::getExpectedNormalizedEntity() + [
+ static::$fieldName => [
+ [
+ 'value' => $this->entity->get(static::$fieldName)->value,
+ ],
+ ],
+ ];
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function getNormalizedPostEntity() {
+ return parent::getNormalizedPostEntity() + [
+ static::$fieldName => [
+ [
+ 'value' => static::$dateString,
+ ],
+ ],
+ ];
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function assertNormalizationEdgeCases($method, Url $url, array $request_options) {
+ parent::assertNormalizationEdgeCases($method, $url, $request_options);
+
+ if ($this->entity->getEntityType()->hasKey('bundle')) {
+ $fieldName = static::$fieldName;
+
+ // DX: 422 when date type is incorrect.
+ $normalization = $this->getNormalizedPostEntity();
+ $normalization[static::$fieldName][0]['value'] = [
+ '2017', '03', '01',
+ ];
+
+ $request_options[RequestOptions::BODY] = $this->serializer->encode($normalization, static::$format);
+ $response = $this->request($method, $url, $request_options);
+ $message = "Unprocessable Entity: validation failed.\n{$fieldName}.0: The datetime value must be a string.\n{$fieldName}.0.value: This value should be of the correct primitive type.\n";
+ $this->assertResourceErrorResponse(422, $message, $response);
+
+ // DX: 422 when date format is incorrect.
+ $normalization = $this->getNormalizedPostEntity();
+ $value = '2017-03-01T01:02:03';
+ $normalization[static::$fieldName][0]['value'] = $value;
+
+ $request_options[RequestOptions::BODY] = $this->serializer->encode($normalization, static::$format);
+ $response = $this->request($method, $url, $request_options);
+ $message = "Unprocessable Entity: validation failed.\n{$fieldName}.0: The datetime value '{$value}' is invalid for the format 'Y-m-d'\n";
+ $this->assertResourceErrorResponse(422, $message, $response);
+
+ // DX: 422 when value is not a valid date.
+ $normalization = $this->getNormalizedPostEntity();
+ $value = '2017-13-55';
+ $normalization[static::$fieldName][0]['value'] = $value;
+
+ $request_options[RequestOptions::BODY] = $this->serializer->encode($normalization, static::$format);
+ $response = $this->request($method, $url, $request_options);
+ $message = "Unprocessable Entity: validation failed.\n{$fieldName}.0: The datetime value '{$value}' did not parse properly for the format 'Y-m-d'\n{$fieldName}.0.value: This value should be of the correct primitive type.\n";
+ $this->assertResourceErrorResponse(422, $message, $response);
+ }
+ }
+
+}