diff --git a/core/lib/Drupal/Component/Plugin/Context/Context.php b/core/lib/Drupal/Component/Plugin/Context/Context.php
index b3f431e..9c6b93c 100644
--- a/core/lib/Drupal/Component/Plugin/Context/Context.php
+++ b/core/lib/Drupal/Component/Plugin/Context/Context.php
@@ -37,7 +37,7 @@ class Context implements ContextInterface {
    *   The context definition.
    */
   public function __construct(ContextDefinitionInterface $context_definition) {
-    $this->setContextDefinition($context_definition);
+    $this->contextDefinition = $context_definition;
   }
 
   /**
diff --git a/core/lib/Drupal/Component/Plugin/Context/ContextDefinitionInterface.php b/core/lib/Drupal/Component/Plugin/Context/ContextDefinitionInterface.php
index 07288f6..25a3dfe 100644
--- a/core/lib/Drupal/Component/Plugin/Context/ContextDefinitionInterface.php
+++ b/core/lib/Drupal/Component/Plugin/Context/ContextDefinitionInterface.php
@@ -155,6 +155,7 @@ public function addConstraint($constraint_name, $options = NULL);
    * @return array
    *   A validation constraint definition which can be used for instantiating a
    *   \Symfony\Component\Validator\Constraint object.
+   *
    * @throws Drupal\Component\Plugin\Exception\ContextException
    *   If $constraint_name is not available, this method throws an exception.
    */
diff --git a/core/tests/Drupal/Tests/Component/Plugin/Context/ContextTest.php b/core/tests/Drupal/Tests/Component/Plugin/Context/ContextTest.php
index 0e996c1..c673607 100644
--- a/core/tests/Drupal/Tests/Component/Plugin/Context/ContextTest.php
+++ b/core/tests/Drupal/Tests/Component/Plugin/Context/ContextTest.php
@@ -87,6 +87,43 @@ public function testGetContextValue($expected, $context_value, $is_required, $da
   }
 
   /**
+   * Helper to build a mocked Drupal\Component\Plugin\Context\Context object.
+   *
+   * @param int $expected_count
+   *   The number of Constraint objects we expect.
+   * @param string $class_constraint
+   *   Value to mock as returned from
+   *   ContextDefinitionInterface::getConstraint('class').
+   *
+   * @return Drupal\Component\Plugin\Context\Context|mock
+   *   A mocked Drupal\Component\Plugin\Context\Context with all expectations
+   *   set.
+   */
+  protected function mockGetConstraintsContext($expected_count, $class_constraint) {
+    // Mock a ContextDefintionInterface object.
+    $context_definition = $this->getMockBuilder('Drupal\Component\Plugin\Context\ContextDefinitionInterface')
+      ->setMethods(array('getConstraint'))
+      ->getMockForAbstractClass();
+    // Set expecations for the context definition object.
+    $context_definition->expects($this->once())
+      ->method('getConstraint')
+      ->with($this->equalTo('class'))
+      ->willReturn($class_constraint);
+
+    // Mock a Context object.
+    $context = $this->getMockBuilder('Drupal\Component\Plugin\Context\Context')
+      ->disableOriginalConstructor()
+      ->setMethods(array('getContextDefinition'))
+      ->getMock();
+    // Set expectations for getContextDefinition().
+    $context->expects($this->once())
+      ->method('getContextDefinition')
+      ->willReturn($context_definition);
+
+    return $context;
+  }
+
+  /**
    * @return array
    *   - Number of elements expected in array returned from getConstraints().
    *   - Value to mock as returned from
@@ -95,6 +132,18 @@ public function testGetContextValue($expected, $context_value, $is_required, $da
   public function providerGetConstraints() {
     return [
       [1, '\stdClass'],
+    ];
+  }
+
+  /**
+   * @return array
+   *   - Number of elements expected in array returned from getConstraints().
+   *   - Value to mock as returned from
+   *     ContextDefinitionInterface::getConstraint('class'). NULL here, which
+   *     should trigger an exception.
+   */
+  public function providerGetConstraintsException() {
+    return [
       [0, NULL],
     ];
   }
@@ -109,32 +158,32 @@ public function testGetConstraints($expected_count, $class_constraint) {
       $this->setExpectedException('Drupal\Component\Plugin\Exception\ContextException');
     }
 
-    // Mock a ContextDefintionInterface object.
-    $context_definition = $this->getMockBuilder('Drupal\Component\Plugin\Context\ContextDefinitionInterface')
-      ->setMethods(array('getConstraint'))
-      ->getMockForAbstractClass();
-    // Set expecations for the context definition object.
-    $context_definition->expects($this->once())
-      ->method('getConstraint')
-      ->with($this->equalTo('class'))
-      ->willReturn($class_constraint);
-
-    // Mock a Context object.
-    $context = $this->getMockBuilder('Drupal\Component\Plugin\Context\Context')
-      ->disableOriginalConstructor()
-      ->setMethods(array('getContextDefinition'))
-      ->getMock();
-    // Set expectations for getContextDefinition().
-    $context->expects($this->once())
-      ->method('getContextDefinition')
-      ->willReturn($context_definition);
+    $mock_context = $this->mockGetConstraintsContext($expected_count, $class_constraint);
 
     // Exercise getConstraints().
-    $constraints = $context->getConstraints();
+    $constraints = $mock_context->getConstraints();
     // Check that getConstraints() returned an array.
     $this->assertInternalType('array', $constraints);
     // Check that getConstraints() returned an array of the correct size.
     $this->assertEquals($expected_count, count($constraints));
+    // Check that all the constraints returned are Context objects as per the
+    // interface documentation.
+    foreach ($constraints as $constraint) {
+      $this->assertInstanceOf('Drupal\Component\Plugin\Context\Context', $constraint);
+    }
+  }
+
+
+  /**
+   * @covers ::getConstraints
+   * @expectedException Drupal\Component\Plugin\Exception\ContextException
+   * @dataProvider providerGetConstraintsException
+   */
+  public function testGetConstraintsException($expected_count, $class_constraint) {
+    $mock_context = $this->mockGetConstraintsContext($expected_count, $class_constraint);
+
+    // Exercise getConstraints().
+    $constraints = $mock_context->getConstraints();
   }
 
 }