diff --git a/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php b/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
index 1c9eced..fa28bc6 100644
--- a/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
+++ b/core/lib/Drupal/Core/Entity/Field/FieldItemBase.php
@@ -91,6 +91,7 @@ public function set($property_name, $value, $notify = TRUE) {
     // value that needs to be updated.
     if (isset($this->properties[$property_name])) {
       $this->properties[$property_name]->setValue($value, FALSE);
+      unset($this->values[$property_name]);
     }
     // Allow setting plain values for not-defined properties also.
     else {
diff --git a/core/lib/Drupal/Core/Entity/Field/Type/Field.php b/core/lib/Drupal/Core/Entity/Field/Type/Field.php
index 4829bb7..469bab7 100644
--- a/core/lib/Drupal/Core/Entity/Field/Type/Field.php
+++ b/core/lib/Drupal/Core/Entity/Field/Type/Field.php
@@ -194,4 +194,19 @@ public function defaultAccess($operation = 'view', User $account = NULL) {
     // Grant access per default.
     return TRUE;
   }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getConstraints() {
+    // Constraints usually apply to the field item, but required does make
+    // sense on the field only. So we special-case it to apply to the field for
+    // now.
+    // @todo: Separate list and list item definitions to separate constraints.
+    $constraints = array();
+    if (!empty($this->definition['required'])) {
+      $constraints[] = \Drupal::typedData()->getValidationConstraintManager()->create('NotNull', array());
+    }
+    return $constraints;
+  }
 }
diff --git a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
index 1dbcc94..663b570 100644
--- a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
+++ b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraintValidator.php
@@ -41,7 +41,7 @@ public function validate($value, Constraint $constraint) {
         // @see \Drupal\Core\TypedData\Validation\PropertyContainerMetadata::accept();
         $property = NULL;
       }
-      $this->context->validateValue($property, $constraints, '[' . $name . ']', $group);
+      $this->context->validateValue($property, $constraints, $name, $group);
     }
   }
 }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityValidationTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityValidationTest.php
index df430f2..df4d8f4 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityValidationTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityValidationTest.php
@@ -56,6 +56,7 @@ public function setUp() {
    * Creates a test entity.
    *
    * @return \Drupal\Core\Entity\EntityInterface
+   *   The created test entity.
    */
   protected function createTestEntity($entity_type) {
     $this->entity_name = $this->randomName();
@@ -97,16 +98,29 @@ protected function checkValidation($entity_type) {
 
     // Test triggering a fail for each of the constraints specified.
     $test_entity = clone $entity;
-    $test_entity->uuid->value = $this->randomString(150);
+    $test_entity->uuid->value = $this->randomString(129);
     $this->assertEqual($test_entity->validate()->count(), 1, 'Validation failed.');
 
     $test_entity = clone $entity;
-    $test_entity->langcode->value = $this->randomString(40);
+    $test_entity->langcode->value = $this->randomString(13);
     $this->assertEqual($test_entity->validate()->count(), 1, 'Validation failed.');
 
     $test_entity = clone $entity;
-    $test_entity->name->value = $this->randomString(40);
+    $test_entity->type->value = NULL;
     $this->assertEqual($test_entity->validate()->count(), 1, 'Validation failed.');
+
+    $test_entity = clone $entity;
+    $test_entity->name->value = $this->randomString(33);
+    $this->assertEqual($test_entity->validate()->count(), 1, 'Validation failed.');
+
+    // Make sure the violation is correct.
+    $violations = $test_entity->validate();
+    $violation = $violations->get(0);
+    $this->assertEqual($violation->getRoot(), $test_entity, 'Violation root is entity.');
+    $this->assertEqual($violation->getPropertyPath(), 'name.0.value', 'Violation property path is correct.');
+
+    $this->assertEqual($violation->getInvalidValue(), $test_entity->name->value, 'Violation contains invalid value.');
+    $this->assertEqual($violation->getMessage(), t('This value is too long. It should have %limit characters or less.', array('%limit' => '32')));
   }
 
 }