diff -u b/src/Tests/MonitoringUITest.php b/src/Tests/MonitoringUITest.php
--- b/src/Tests/MonitoringUITest.php
+++ b/src/Tests/MonitoringUITest.php
@@ -123,7 +123,8 @@
 
     // Get every available field for the entity type node.
     $node_fields = \Drupal::entityManager()->getBaseFieldDefinitions('node');
-    $this->addFields($node_fields, $edit);
+    $edit = $this->addAllVerboseFields($node_fields, $edit);
+    $this->drupalPostForm(NULL, $edit, t('Save'));
 
     $this->assertText(SafeMarkup::format('Sensor @label saved.', array('@label' => 'Node Entity Aggregator sensor')));
 
@@ -189,7 +190,8 @@
     $file_fields = \Drupal::entityManager()->getBaseFieldDefinitions('file');
 
     $edit = array();
-    $this->addFields($file_fields, $edit);
+    $edit = $this->addAllVerboseFields($file_fields, $edit);
+    $this->drupalPostForm(NULL, $edit, t('Save'));
 
     $this->assertText(SafeMarkup::format('Sensor @label saved.', array('@label' => 'File Entity Aggregator sensor')));
 
@@ -1069,14 +1071,17 @@
    *   Fields of an entity type to be added to the form.
    * @param array $edit
    *   Field data in an associative array.
+   *
+   * @return array
+   *   An array with all verbose fields.
    */
-  public function addFields($fields = array(), $edit = array()) {
+  public function addAllVerboseFields($fields = array(), $edit = array()) {
     $i = 2;
     foreach ($fields as $field) {
       $this->drupalPostForm(NULL, array(), t('Add another field'));
-      $array['settings[verbose_fields][' . $i++ . ']'] = $field->getName();
+      $edit['settings[verbose_fields][' . $i++ . ']'] = $field->getName();
     }
-    $this->drupalPostForm(NULL, $edit, t('Save'));
+    return $edit;
   }
 
 }