diff --git a/core/tests/Drupal/Setup/Commands/TestInstallationSetupCommand.php b/core/tests/Drupal/Setup/Commands/TestInstallationSetupCommand.php
index 9c0cbfe15d..0b622a284a 100644
--- a/core/tests/Drupal/Setup/Commands/TestInstallationSetupCommand.php
+++ b/core/tests/Drupal/Setup/Commands/TestInstallationSetupCommand.php
@@ -68,15 +68,15 @@ protected function execute(InputInterface $input, OutputInterface $output) {
     $output->writeln(drupal_generate_test_ua($test->getDatabasePrefix()));
   }
 
-  protected function bootstrapDrupal($autoloader) {
+  protected function bootstrapDrupal() {
     $request = Request::createFromGlobals();
-    $kernel = DrupalKernel::createFromRequest($request, $autoloader, $this->getApplication()->getName());
+    $kernel = DrupalKernel::createFromRequest($request, $this->autoloader, $this->getApplication()->getName());
     DrupalKernel::bootEnvironment($kernel->getAppRoot());
 
     Settings::initialize(
       dirname(dirname(dirname(dirname(__DIR__)))),
       DrupalKernel::findSitePath($request),
-      $autoloader
+      $this->autoloader
     );
   }
 
diff --git a/core/tests/Drupal/Setup/SetupDrupalTestScript.php b/core/tests/Drupal/Setup/SetupDrupalTestScript.php
index 707e3a5ded..d8f7e1fbc9 100644
--- a/core/tests/Drupal/Setup/SetupDrupalTestScript.php
+++ b/core/tests/Drupal/Setup/SetupDrupalTestScript.php
@@ -3,9 +3,7 @@
 namespace Drupal\Setup;
 
 /**
- * Tests setup-drupal-test.php.
- *
- * @group core
+ * Setup file used by \Drupal\KernelTests\Setup\Commands\SetupDrupalTestScriptTest
  */
 class SetupDrupalTestScript implements TestSetupInterface {
 
diff --git a/core/tests/Drupal/Setup/TestInstallationSetup.php b/core/tests/Drupal/Setup/TestInstallationSetup.php
index c57ad52bc4..50b027a10a 100644
--- a/core/tests/Drupal/Setup/TestInstallationSetup.php
+++ b/core/tests/Drupal/Setup/TestInstallationSetup.php
@@ -88,7 +88,11 @@ protected function installDrupal() {
    * Uses the setup file to configure Drupal.
    *
    * @param string $class
-   *   The setup class.
+   *   The full qualified class name, which should setup Drupal for tests. One common need for
+   *   example would be to create the required content types and fields.
+   *   The class needs to implement \Drupal\Setup\TestSetupInterface
+   *
+   * @see \Drupal\Setup\TestSetupInterface
    */
   protected function executeSetupClass($class) {
     if (!class_exists($class)) {