diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index 25139e6..7b4d74c 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -1825,9 +1825,13 @@ abstract class WebTestBase extends TestBase {
 
     if (isset($urls[$index])) {
       $url_target = $this->getAbsoluteUrl($urls[$index]['href']);
+      $assert_msg = t('Clicked link %label (@url_target) from @url_before', array('%label' => $label, '@url_target' => $url_target, '@url_before' => $url_before));
+    }
+    else {
+      $assert_msg = t('The link %label from @url_before was not found', array('%label' => $label, '@url_before' => $url_before));
     }
 
-    $this->assertTrue(isset($urls[$index]), t('Clicked link %label (@url_target) from @url_before', array('%label' => $label, '@url_target' => $url_target, '@url_before' => $url_before)), t('Browser'));
+    $this->assertTrue(isset($urls[$index]), $assert_msg, t('Browser'));
 
     if (isset($url_target)) {
       return $this->drupalGet($url_target);