commit c828d15df07b03d3cc1c76e6ae94701cba1ee20e
Author: fago <fago@wolfgangziegler.net>
Date:   Sun Feb 28 18:13:32 2016 +0100

    Add some more test coverage and undo some problematic changes.

diff --git a/core/lib/Drupal/Core/TypedData/DataDefinition.php b/core/lib/Drupal/Core/TypedData/DataDefinition.php
index 6e6f461..743fe70 100644
--- a/core/lib/Drupal/Core/TypedData/DataDefinition.php
+++ b/core/lib/Drupal/Core/TypedData/DataDefinition.php
@@ -6,16 +6,12 @@
  */
 
 namespace Drupal\Core\TypedData;
-use Drupal\Core\DependencyInjection\DependencySerializationTrait;
 
 /**
  * A typed data definition class for defining data based on defined data types.
  */
 class DataDefinition implements DataDefinitionInterface, \ArrayAccess {
 
-  use DependencySerializationTrait;
-  use TypedDataTrait;
-
   /**
    * The array holding values for all definition keys.
    *
diff --git a/core/lib/Drupal/Core/TypedData/TypedDataManager.php b/core/lib/Drupal/Core/TypedData/TypedDataManager.php
index ca87977..adf91c9 100644
--- a/core/lib/Drupal/Core/TypedData/TypedDataManager.php
+++ b/core/lib/Drupal/Core/TypedData/TypedDataManager.php
@@ -122,10 +122,7 @@ public function createDataDefinition($data_type) {
       throw new \InvalidArgumentException("Invalid data type '$data_type' has been given");
     }
     $class = $type_definition['definition_class'];
-    $data_definition = $class::createFromDataType($data_type);
-    $data_definition->setTypedDataManager($this);
-
-    return $data_definition;
+    return $class::createFromDataType($data_type);
   }
 
   /**
diff --git a/core/modules/config/tests/config_test/src/ConfigValidation.php b/core/modules/config/tests/config_test/src/ConfigValidation.php
index 9da6862..19729e2 100644
--- a/core/modules/config/tests/config_test/src/ConfigValidation.php
+++ b/core/modules/config/tests/config_test/src/ConfigValidation.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\config_test;
 
+
 class ConfigValidation {
 
   public static function validateLlama($object, $context) {
diff --git a/core/tests/Drupal/KernelTests/Config/ConfigValidationTest.php b/core/tests/Drupal/KernelTests/Config/ConfigValidationTest.php
index c9796dd..f75dd8b 100644
--- a/core/tests/Drupal/KernelTests/Config/ConfigValidationTest.php
+++ b/core/tests/Drupal/KernelTests/Config/ConfigValidationTest.php
@@ -6,11 +6,18 @@
  */
 
 namespace Drupal\KernelTests\Config;
+
+use Drupal\Core\TypedData\ComplexDataInterface;
+use Drupal\Core\TypedData\ListInterface;
+use Drupal\Core\TypedData\Type\IntegerInterface;
+use Drupal\Core\TypedData\Type\StringInterface;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\Validator\ConstraintViolationListInterface;
 
 /**
- * Tests config validation mechanism
+ * Tests config validation mechanism.
+ *
+ * @group config
  */
 class ConfigValidationTest extends KernelTestBase {
 
@@ -28,6 +35,51 @@ protected function setUp() {
     $this->installConfig('config_test');
   }
 
+  /**
+   * Verifies that the Typed Data API is implemented correctly.
+   */
+  public function testTypedDataAPI() {
+
+    /** @var \Drupal\Core\Config\TypedConfigManagerInterface $typed_config_manager */
+    $typed_config_manager = \Drupal::service('config.typed');
+    /** @var \Drupal\Core\Config\Schema\TypedConfigInterface $typed_config */
+    $typed_config = $typed_config_manager->get('config_test.validation');
+
+    // Test a primitive.
+    $string_data = $typed_config->get('llama');
+    $this->assertInstanceOf(StringInterface::class, $string_data);
+    $this->assertEquals('meh', $string_data->getValue());
+
+    // Test complex data.
+    $mapping = $typed_config->get('cat');
+    /** @var \Drupal\Core\TypedData\ComplexDataInterface $mapping */
+    $this->assertInstanceOf(ComplexDataInterface::class, $mapping);
+    $this->assertInstanceOf(StringInterface::class, $mapping->get('type'));
+    $this->assertEquals('kitten', $mapping->get('type')->getValue());
+    $this->assertInstanceOf(IntegerInterface::class, $mapping->get('count'));
+    $this->assertEquals(2, $mapping->get('count')->getValue());
+    // Verify the metadata is available.
+    $definitions = $mapping->getDataDefinition()->getPropertyDefinitions();
+    $this->assertArrayHasKey('type', $definitions);
+    $this->assertArrayHasKey('count', $definitions);
+    $this->assertEquals('string', $definitions['type']->getDataType());
+    $this->assertEquals('integer', $definitions['count']->getDataType());
+
+    // Test accessing sequences as list data. Other than sequences, lists do
+    // not support keys. The items appear just with numeric indices.
+    $sequence = $typed_config->get('giraffe');
+    /** @var \Drupal\Core\TypedData\ListInterface $sequence */
+    $this->assertInstanceOf(ListInterface::class, $sequence);
+    $this->assertInstanceOf(StringInterface::class, $sequence->get(0));
+    $this->assertEquals('hum1', $sequence->get(0)->getValue());
+    $this->assertEquals('hum2', $sequence->get(1)->getValue());
+    $this->assertEquals(2, $sequence->count());
+    // Verify the item metadata is available.
+    $definition = $sequence->getDataDefinition()->getItemDefinition();
+    $this->assertEquals('string', $definition->getDataType());
+  }
+
+
   public function testSimpleConfigValidation() {
     $config = \Drupal::configFactory()->getEditable('config_test.validation');
     /** @var \Drupal\Core\Config\TypedConfigManagerInterface $typed_config_manager */