diff --git a/core/modules/node/lib/Drupal/node/Tests/SummaryLengthTest.php b/core/modules/node/lib/Drupal/node/Tests/SummaryLengthTest.php
index 9936454..95e64f0 100644
--- a/core/modules/node/lib/Drupal/node/Tests/SummaryLengthTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/SummaryLengthTest.php
@@ -35,24 +35,26 @@ function testSummaryLength() {
     $web_user = $this->drupalCreateUser(array('access content', 'administer content types'));
     $this->loggedInUser = $web_user;
 
-    // Render the node as teaser.
+    // Render the node as a teaser.
     $content = entity_render_controller('node')->view($node, 'teaser');
     $this->drupalSetContent(drupal_render($content));
-    // The node teaser when it has 600 characters in length
+    // The string 'What is a Drupalism?' is between the 200th and 600th
+    // characters of the node body, so it should be included if the summary is
+    // 600 characters long.
     $expected = 'What is a Drupalism?';
-    $this->assertRaw($expected, 'Check that the summary is 600 characters in length', 'Node');
+    $this->assertRaw($expected);
 
     // Change the teaser length for "Basic page" content type.
     $instance = field_info_instance('node', 'body', $node->type);
     $instance['display']['teaser']['settings']['trim_length'] = 200;
     field_update_instance($instance);
 
-    // Render the node as teaser again and check if the summary is now only 200
-    // characters in length.
+    // Render the node as a teaser again and check that the summary is now only
+    // 200 characters in length and so does not include 'What is a Drupalism?'.
     $content = entity_render_controller('node')->view($node, 'teaser');
     $this->drupalSetContent(drupal_render($content));
     $this->assertText($node->label());
-    $this->assertNoRaw($expected, 'Check that the summary is not longer than 200 characters', 'Node');
+    $this->assertNoRaw($expected);
   }
 
 }