diff --git a/core/modules/simpletest/lib/Drupal/simpletest/ConfigMemoryStorage.php b/core/modules/simpletest/lib/Drupal/simpletest/ConfigMemoryStorage.php
new file mode 100644
index 0000000..096ad55
--- /dev/null
+++ b/core/modules/simpletest/lib/Drupal/simpletest/ConfigMemoryStorage.php
@@ -0,0 +1,95 @@
+<?php
+
+namespace Drupal\simpletest;
+
+use Drupal\Core\Config\StorageInterface;
+
+class ConfigMemoryStorage implements StorageInterface {
+
+  protected $moduleList;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function exists($name)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function read($name)
+  {
+   if ($name == 'system.module') {
+     return $this->moduleList;
+   }
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function write($name, array $data)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function delete($name)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function rename($name, $new_name)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function encode($data)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function decode($raw)
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function listAll($prefix = '')
+  {
+
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function deleteAll($prefix = '')
+  {
+
+  }
+
+  /**
+   * Sets the module list that will be returned to the module handler.
+   *
+   * @param $module_list
+   */
+  public function setModuleList($module_list) {
+    $this->moduleList = $module_list;
+  }
+
+}
\ No newline at end of file
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
index b2a35b1..a8bcd4e 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
@@ -13,6 +13,8 @@
 use Symfony\Component\DependencyInjection\Reference;
 use Drupal\Core\Database\Database;
 use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Config\BootstrapConfigStorageFactory;
+use Drupal\Component\Utility\Settings;
 
 /**
  * Base test case class for Drupal unit tests.
@@ -62,6 +64,8 @@
    */
   protected $keyValueFactory;
 
+  protected $bootstrapConfig;
+
   /**
    * Overrides \Drupal\simpletest\UnitTestBase::__construct().
    */
@@ -77,6 +81,7 @@ function __construct($test_id = NULL) {
    * @see DrupalUnitTestBase
    */
   protected function setUp() {
+    $this->bootstrapConfig = new ConfigMemoryStorage();
     // Copy/prime extension file lists once to avoid filesystem scans.
     if (!isset($this->moduleFiles)) {
       $this->moduleFiles = \Drupal::state()->get('system.module.files') ?: array();
@@ -95,7 +100,11 @@ protected function setUp() {
     \Drupal::state()->set('system.module.files', $this->moduleFiles);
     \Drupal::state()->set('system.theme.files', $this->themeFiles);
     \Drupal::state()->set('system.theme.data', $this->themeData);
-
+    $settings = settings()->getAll();
+    $settings['drupal_bootstrap_config_storage'] = array($this, 'getBootstrapConfig');
+    // Calling the constructor will update the instance that gets returned for all
+    // future calls to Settings::getSingleton().
+    $settings_object = new Settings($settings);
     // Bootstrap the kernel.
     // No need to dump it; this test runs in-memory.
     $this->kernel = new DrupalKernel('unit_testing', TRUE, drupal_classloader(), FALSE);
@@ -124,6 +133,10 @@ protected function setUp() {
     config('system.theme')->set('default', 'stark');
   }
 
+  public function getBootstrapConfig() {
+    return $this->bootstrapConfig;
+  }
+
   protected function tearDown() {
     $this->kernel->shutdown();
     parent::tearDown();
@@ -263,6 +276,13 @@ protected function enableModules(array $modules) {
     }
     $module_handler->setModuleList($module_filenames);
     $module_handler->resetImplementations();
+    $module_config = array('enabled' => array());
+    $weight = 0;
+    foreach ($module_filenames as $module => $filename) {
+      $module_config['enabled'][$module] = $weight++;
+    }
+    $this->bootstrapConfig->setModuleList($module_config);
+
     // Update the kernel to make their services available.
     \Drupal::service('event_dispatcher')->dispatch('drupal.update_modules');
 
@@ -295,6 +315,12 @@ protected function disableModules(array $modules) {
     }
     $module_handler->setModuleList($module_filenames);
     $module_handler->resetImplementations();
+    $module_config = array('enabled' => array());
+    $weight = 0;
+    foreach ($module_filenames as $module => $filename) {
+      $module_config['enabled'][$module] = $weight++;
+    }
+    $this->bootstrapConfig->setModuleList($module_config);
     // Update the kernel to remove their services.
     Drupal::service('event_dispatcher')->dispatch('drupal.update_modules');