diff --git a/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php b/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
new file mode 100644
index 0000000..a69f98e
--- /dev/null
+++ b/core/tests/Drupal/Tests/Core/Field/BaseFieldDefinitionTestBase.php
@@ -0,0 +1,79 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\Tests\Core\Fied\BaseFieldDefinitionTestBase.
+ */
+
+namespace Drupal\Tests\Core\Field;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\Field\FieldTypePluginManager;
+use Drupal\Core\Language\Language;
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * Provides a test base class for testing field definitions.
+ */
+abstract class BaseFieldDefinitionTestBase extends UnitTestCase {
+
+  /**
+   * The field definition used in this test.
+   *
+   * @var \Drupal\Core\Field\BaseFieldDefinition
+   */
+  protected $definition;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setUp() {
+
+    // getModuleAndPath() returns an array of the module name and directory.
+    list($module_name, $module_dir) = $this->getModuleAndPath();
+
+    $namespaces = new \ArrayObject();
+    $namespaces["Drupal\\$module_name"] = $module_dir . '/src';
+
+    $module_handler = $this->getMock('Drupal\Core\Extension\ModuleHandlerInterface');
+    $module_handler->expects($this->once())
+      ->method('moduleExists')
+      ->with($module_name)
+      ->will($this->returnValue(TRUE));
+    $plugin_manager = new FieldTypePluginManager(
+      $namespaces,
+      $this->getMock('Drupal\Core\Cache\CacheBackendInterface'),
+      $module_handler
+    );
+
+    $container = new ContainerBuilder();
+    $container->set('plugin.manager.field.field_type', $plugin_manager);
+    // The 'string_translation' service is used by the @Translation annotation.
+    $container->set('string_translation', $this->getStringTranslationStub());
+    \Drupal::setContainer($container);
+
+    $this->definition = BaseFieldDefinition::create($this->getPluginId());
+  }
+
+  /**
+   * Returns the plugin ID of the tested field type.
+   *
+   * @return string
+   *   The plugin ID.
+   */
+  abstract protected function getPluginId();
+
+  /**
+   * Returns the module name and the module directory for the plugin.
+   *
+   * drupal_get_path() cannot be used here, because it is not available in
+   * Drupal PHPUnit tests.
+   *
+   * @return array
+   *   A one-dimensional array containing the following strings:
+   *   - The module name.
+   *   - The module directory, e.g. DRUPAL_CORE . 'core/modules/path'.
+   */
+  abstract protected function getModuleAndPath();
+
+}
diff --git a/core/tests/Drupal/Tests/Core/Field/FieldDefinitionTestBase.php b/core/tests/Drupal/Tests/Core/Field/FieldDefinitionTestBase.php
deleted file mode 100644
index a69f98e..0000000
--- a/core/tests/Drupal/Tests/Core/Field/FieldDefinitionTestBase.php
+++ /dev/null
@@ -1,79 +0,0 @@
-<?php
-/**
- * @file
- * Contains \Drupal\Tests\Core\Fied\BaseFieldDefinitionTestBase.
- */
-
-namespace Drupal\Tests\Core\Field;
-
-use Drupal\Core\DependencyInjection\ContainerBuilder;
-use Drupal\Core\Field\BaseFieldDefinition;
-use Drupal\Core\Field\FieldTypePluginManager;
-use Drupal\Core\Language\Language;
-use Drupal\Tests\UnitTestCase;
-
-/**
- * Provides a test base class for testing field definitions.
- */
-abstract class BaseFieldDefinitionTestBase extends UnitTestCase {
-
-  /**
-   * The field definition used in this test.
-   *
-   * @var \Drupal\Core\Field\BaseFieldDefinition
-   */
-  protected $definition;
-
-  /**
-   * {@inheritdoc}
-   */
-  public function setUp() {
-
-    // getModuleAndPath() returns an array of the module name and directory.
-    list($module_name, $module_dir) = $this->getModuleAndPath();
-
-    $namespaces = new \ArrayObject();
-    $namespaces["Drupal\\$module_name"] = $module_dir . '/src';
-
-    $module_handler = $this->getMock('Drupal\Core\Extension\ModuleHandlerInterface');
-    $module_handler->expects($this->once())
-      ->method('moduleExists')
-      ->with($module_name)
-      ->will($this->returnValue(TRUE));
-    $plugin_manager = new FieldTypePluginManager(
-      $namespaces,
-      $this->getMock('Drupal\Core\Cache\CacheBackendInterface'),
-      $module_handler
-    );
-
-    $container = new ContainerBuilder();
-    $container->set('plugin.manager.field.field_type', $plugin_manager);
-    // The 'string_translation' service is used by the @Translation annotation.
-    $container->set('string_translation', $this->getStringTranslationStub());
-    \Drupal::setContainer($container);
-
-    $this->definition = BaseFieldDefinition::create($this->getPluginId());
-  }
-
-  /**
-   * Returns the plugin ID of the tested field type.
-   *
-   * @return string
-   *   The plugin ID.
-   */
-  abstract protected function getPluginId();
-
-  /**
-   * Returns the module name and the module directory for the plugin.
-   *
-   * drupal_get_path() cannot be used here, because it is not available in
-   * Drupal PHPUnit tests.
-   *
-   * @return array
-   *   A one-dimensional array containing the following strings:
-   *   - The module name.
-   *   - The module directory, e.g. DRUPAL_CORE . 'core/modules/path'.
-   */
-  abstract protected function getModuleAndPath();
-
-}