diff -u b/core/modules/system/lib/Drupal/system/Tests/Block/SystemMenuBlockTest.php b/core/modules/system/lib/Drupal/system/Tests/Block/SystemMenuBlockTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/Block/SystemMenuBlockTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Block/SystemMenuBlockTest.php
@@ -10,8 +10,8 @@
 /**
  * Tests \Drupal\system\Plugin\Block\SystemMenuBlock
  *
- * @todo improve the test to include coverage of all SystemMenuBlock related
- *   functionality. For example, block_menu_delete().
+ * @todo Expand test coverage to all SystemMenuBlock functionality, including
+ *   block_menu_delete().
  */
 class SystemMenuBlockTest extends DrupalUnitTestBase {
 
@@ -30,6 +30,9 @@
     );
   }
 
+  /**
+   * Tests calculation of a system menu block's configuration dependencies.
+   */
   public function testSystemMenuBlockConfigDependencies() {
     // Add a new custom menu.
     $menu_name = $this->randomName(16);