diff --git a/core/modules/rest/src/Plugin/rest/resource/UserRegistrationResource.php b/core/modules/rest/src/Plugin/rest/resource/UserRegistrationResource.php
index 25b895f..51bb3d4 100644
--- a/core/modules/rest/src/Plugin/rest/resource/UserRegistrationResource.php
+++ b/core/modules/rest/src/Plugin/rest/resource/UserRegistrationResource.php
@@ -20,7 +20,10 @@
  * @RestResource(
  *   id = "rest_user_registration",
  *   label = @Translation("User Registration"),
- *   serialization_class = "Drupal\user\Entity\User"
+ *   serialization_class = "Drupal\user\Entity\User",
+ *   uri_paths = {
+ *     "https://www.drupal.org/link-relations/create" = "/user/register",
+ *   },
  * )
  */
 class UserRegistrationResource extends ResourceBase {
@@ -105,6 +108,7 @@ public function post(UserInterface $account = NULL) {
       throw new AccessDeniedHttpException('Only anonymous users can register users.');
     }
     $approvalSettings = $this->userSettings->get('register');
+
     // Verify that the current user can register a user account.
     if ($approvalSettings == USER_REGISTER_ADMINISTRATORS_ONLY) {
       throw new AccessDeniedHttpException('Only administrators can register users.');
@@ -148,7 +152,7 @@ public function post(UserInterface $account = NULL) {
       _user_mail_notify('register_pending_approval', $account);
     }
 
-    $url = $account->urlInfo('canonical', ['absolute' => TRUE])->toString(TRUE);
+    $url = $account->toUrl('canonical', ['absolute' => TRUE])->toString(TRUE);
     $response = new ModifiedResourceResponse(NULL, 201, ['Location' => $url->getGeneratedUrl()]);
 
     return $response;
@@ -160,7 +164,7 @@ public function post(UserInterface $account = NULL) {
   public function routes() {
     $collection = new RouteCollection();
 
-    $route = $this->getBaseRoute('/entity/user/register', 'POST');
+    $route = $this->getBaseRoute('/user/register', 'POST');
 
     // Restrict the incoming HTTP Content-type header to the known serialization
     // formats.
@@ -186,7 +190,7 @@ protected function validate(UserInterface $entity) {
     // changes.
     $violations->filterByFieldAccess();
 
-    if (count($violations) > 0) {
+    if ($violations->count() > 0) {
       $message = "Unprocessable Entity: validation failed.\n";
       foreach ($violations as $violation) {
         $message .= $violation->getPropertyPath() . ': ' . $violation->getMessage() . "\n";
diff --git a/core/modules/rest/src/Tests/RegisterUserTest.php b/core/modules/rest/src/Tests/RegisterUserTest.php
index d2b5c4a..bda801c 100644
--- a/core/modules/rest/src/Tests/RegisterUserTest.php
+++ b/core/modules/rest/src/Tests/RegisterUserTest.php
@@ -5,7 +5,6 @@
 use Drupal\user\Entity\Role;
 use Drupal\user\RoleInterface;
 
-
 /**
  * Tests User Registration.
  *
@@ -51,7 +50,7 @@ public function setUp() {
   /**
    * Tests user registration from REST.
    */
-  protected function testRegisterUser() {
+  public function testRegisterUser() {
 
     // New user info to be serialized.
     $data = [
diff --git a/core/modules/rest/tests/src/Unit/UserRegistrationResourceTest.php b/core/modules/rest/tests/src/Unit/UserRegistrationResourceTest.php
index 28cfcbe..93fdfa1 100644
--- a/core/modules/rest/tests/src/Unit/UserRegistrationResourceTest.php
+++ b/core/modules/rest/tests/src/Unit/UserRegistrationResourceTest.php
@@ -85,20 +85,14 @@ class UserRegistrationResourceTest extends UnitTestCase {
   protected function setUp() {
     parent::setUp();
 
-    $this->logger = $this->getMock(LoggerInterface::class);
+    $this->logger = $this->prophesize(LoggerInterface::class)->reveal();
 
-    $this->userSettings = $this->getMockBuilder(ImmutableConfig::class)
-      ->setMethods(['get'])
-      ->disableOriginalConstructor()
-      ->getMock();
+    $this->userSettings = $this->prophesize(ImmutableConfig::class);
 
-    $this->currentUser = $this->getMockBuilder(AccountInterface::class)
-      ->disableOriginalConstructor()
-      ->getMock();
+    $this->currentUser = $this->prophesize(AccountInterface::class);
 
-    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings, $this->currentUser);
+    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings->reveal(), $this->currentUser->reveal());
     $this->reflection = new \ReflectionClass($this->testClass);
-
   }
 
   /**
@@ -120,27 +114,17 @@ public function getProtectedMethod($method) {
    * Tests that the user entity does not violate any validation constraints.
    */
   public function testValidate() {
-    $violations = $this->getMockBuilder(EntityConstraintViolationList::class)
-      ->setMethods(['filterByFieldAccess'])
-      ->disableOriginalConstructor()
-      ->getMock();
+    $violations = $this->prophesize(EntityConstraintViolationList::class);
+    $violations->filterByFieldAccess()->willReturn([]);
+    $violations->count()->willReturn(0);
 
-    $violations->expects($this->once())
-      ->method('filterByFieldAccess')
-      ->will($this->returnValue(array()));
-
-    $entity = $this->getMockBuilder(User::class)
-      ->disableOriginalConstructor()
-      ->getMock();
-
-    $entity->expects($this->once())
-      ->method('validate')
-      ->will($this->returnValue($violations));
+    $entity = $this->prophesize(User::class);
+    $entity->validate()->willReturn($violations->reveal());
 
     $method = $this->getProtectedMethod('validate');
 
     // No exception is thrown.
-    $method->invokeArgs($this->testClass, [$entity]);
+    $method->invokeArgs($this->testClass, [$entity->reveal()]);
   }
 
   /**
@@ -150,32 +134,18 @@ public function testValidate() {
    * @expectedException UserRegistrationResourceTest::ERROR_MESSAGE
    */
   public function testFailedValidate() {
-    $violation1 = $this->getMock(ConstraintViolationInterface::class);
-
-    $violation1->expects($this->once())
-      ->method('getPropertyPath')
-      ->will($this->returnValue('property_path'));
+    $violation1 = $this->prophesize(ConstraintViolationInterface::class);
+    $violation1->getPropertyPath()->willReturn('property_path');
+    $violation1->getMessage()->willReturn('message');
 
-    $violation1->expects($this->once())
-      ->method('getMessage')
-      ->will($this->returnValue('message'));
+    $violation2 = $this->prophesize(ConstraintViolationInterface::class);
+    $violation2->getPropertyPath()->willReturn('property_path');
+    $violation2->getMessage()->willReturn('message');
 
-    $violation2 = $this->getMock(ConstraintViolationInterface::class);
-
-    $violation2->expects($this->once())
-      ->method('getPropertyPath')
-      ->will($this->returnValue('property_path_2'));
-
-    $violation2->expects($this->once())
-      ->method('getMessage')
-      ->will($this->returnValue('message_2'));
-
-    $entity = $this->getMockBuilder(User::class)
-      ->disableOriginalConstructor()
-      ->getMock();
+    $entity = $this->prophesize(User::class);
 
     $violations = $this->getMockBuilder(EntityConstraintViolationList::class)
-      ->setConstructorArgs([$entity, [$violation1, $violation2]])
+      ->setConstructorArgs([$entity->reveal(), [$violation1->reveal(), $violation2->reveal()]])
       ->setMethods(['filterByFieldAccess'])
       ->getMock();
 
@@ -183,13 +153,11 @@ public function testFailedValidate() {
       ->method('filterByFieldAccess')
       ->will($this->returnValue([]));
 
-    $entity->expects($this->once())
-      ->method('validate')
-      ->will($this->returnValue($violations));
+    $entity->validate()->willReturn($violations);
 
     $method = $this->getProtectedMethod('validate');
 
-    $method->invoke($this->testClass, $entity);
+    $method->invoke($this->testClass, $entity->reveal());
   }
 
   /**
@@ -209,15 +177,10 @@ public function testEmptyPost() {
    * @expectedExceptionMessage An ID has been set and only new user accounts can be registered.
    */
   public function testExistedEntityPost() {
-    $entity = $this->getMockBuilder(User::class)
-      ->disableOriginalConstructor()
-      ->getMock();
+    $entity = $this->prophesize(User::class);
+    $entity->isNew()->willReturn(FALSE);
 
-    $entity->expects($this->once())
-      ->method('isNew')
-      ->will($this->returnValue(FALSE));
-
-    $this->testClass->post($entity);
+    $this->testClass->post($entity->reveal());
   }
 
   /**
@@ -227,24 +190,17 @@ public function testExistedEntityPost() {
    * @expectedExceptionMessage Only administrators can register users.
    */
   public function testRegistrationAdminOnlyPost() {
-    $this->currentUser->expects($this->once())
-      ->method('isAnonymous')
-      ->will($this->returnValue(TRUE));
 
-    $this->userSettings->expects($this->once())
-      ->method('get')
-      ->will($this->returnValue(USER_REGISTER_ADMINISTRATORS_ONLY));
+    $this->userSettings->get('register')->willReturn(USER_REGISTER_ADMINISTRATORS_ONLY);
 
-    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings, $this->currentUser);
-    $entity = $this->getMockBuilder(User::class)
-      ->disableOriginalConstructor()
-      ->getMock();
+    $this->currentUser->isAnonymous()->willReturn(TRUE);
 
-    $entity->expects($this->once())
-      ->method('isNew')
-      ->will($this->returnValue(TRUE));
+    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings->reveal(), $this->currentUser->reveal());
 
-    $this->testClass->post($entity);
+    $entity = $this->prophesize(User::class);
+    $entity->isNew()->willReturn(TRUE);
+
+    $this->testClass->post($entity->reveal());
   }
 
   /**
@@ -254,21 +210,14 @@ public function testRegistrationAdminOnlyPost() {
    * @expectedExceptionMessage Only anonymous users can register users.
    */
   public function testRegistrationAnonymousOnlyPost() {
-    $this->currentUser->expects($this->once())
-      ->method('isAnonymous')
-      ->will($this->returnValue(FALSE));
+    $this->currentUser->isAnonymous()->willReturn(FALSE);
 
-    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings, $this->currentUser);
+    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings->reveal(), $this->currentUser->reveal());
 
-    $entity = $this->getMockBuilder(User::class)
-      ->disableOriginalConstructor()
-      ->getMock();
+    $entity = $this->prophesize(User::class);
+    $entity->isNew()->willReturn(TRUE);
 
-    $entity->expects($this->once())
-      ->method('isNew')
-      ->will($this->returnValue(TRUE));
-
-    $this->testClass->post($entity);
+    $this->testClass->post($entity->reveal());
   }
 
   /**
@@ -278,11 +227,9 @@ public function testRegistrationAnonymousOnlyPost() {
    * @expectedExceptionMessage Access denied on creating field 'test_field'.
    */
   public function testFieldAccessValidation() {
-    $this->currentUser->expects($this->once())
-      ->method('isAnonymous')
-      ->will($this->returnValue(TRUE));
+    $this->currentUser->isAnonymous()->willReturn(TRUE);
 
-    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings, $this->currentUser);
+    $this->testClass = new UserRegistrationResource([], 'plugin_id', '', [], $this->logger, $this->userSettings->reveal(), $this->currentUser->reveal());
 
     $entity = $this->getMockBuilder(User::class)
       ->disableOriginalConstructor()