diff --git a/core/tests/Drupal/Tests/Core/Block/BlockManagerTest.php b/core/tests/Drupal/Tests/Core/Block/BlockManagerTest.php
index 796146d..c14964c 100644
--- a/core/tests/Drupal/Tests/Core/Block/BlockManagerTest.php
+++ b/core/tests/Drupal/Tests/Core/Block/BlockManagerTest.php
@@ -42,15 +42,15 @@ protected function setUp() {
       ],
       'block1' => [
         'admin_label' => 'Coconut',
-        'category' => 'expected_category',
+        'category' => 'Group 2',
       ],
       'block2' => [
         'admin_label' => 'Apple',
-        'category' => 'expected_category',
+        'category' => 'Group 1',
       ],
       'block3' => [
         'admin_label' => 'Banana',
-        'category' => 'expected_category',
+        'category' => 'Group 2',
       ],
     ]);
     // Force the discovery object onto the block manager.
@@ -80,8 +80,9 @@ public function testSortedDefinitions() {
    */
   public function testGroupedDefinitions() {
     $definitions = $this->blockManager->getGroupedDefinitions();
-    $this->assertArrayHasKey('expected_category', $definitions);
-    $this->assertSame(['block2', 'block3', 'block1'], array_keys($definitions['expected_category']));
+    $this->assertSame(['Group 1', 'Group 2'], array_keys($definitions));
+    $this->assertSame(['block2'], array_keys($definitions['Group 1']));
+    $this->assertSame(['block3', 'block1'], array_keys($definitions['Group 2']));
   }
 
 }