Issue #1421410 by andypost, Niklas Fiekas: Fixed not defined in form_pre_render_conditional_form_element().

includes/form.inc

@@ -2808,6 +2808,9 @@ function theme_radios($variables) {
   if (!empty($element['#attributes']['class'])) {
     $attributes['class'] .= ' ' . implode(' ', $element['#attributes']['class']);
   }
+  if (isset($element['#attributes']['title'])) {
+    $attributes['title'] = $element['#attributes']['title'];
+  }
   return '<div' . drupal_attributes($attributes) . '>' . (!empty($element['#children']) ? $element['#children'] : '') . '</div>';
 }
 
@@ -3070,6 +3073,9 @@ function theme_checkboxes($variables) {
   if (!empty($element['#attributes']['class'])) {
     $attributes['class'] = array_merge($attributes['class'], $element['#attributes']['class']);
   }
+  if (isset($element['#attributes']['title'])) {
+    $attributes['title'] = $element['#attributes']['title'];
+  }
   return '<div' . drupal_attributes($attributes) . '>' . (!empty($element['#children']) ? $element['#children'] : '') . '</div>';
 }
 
@@ -3079,6 +3085,7 @@ function theme_checkboxes($variables) {
  * This is used as a pre render function for checkboxes and radios.
  */
 function form_pre_render_conditional_form_element($element) {
+  $t = get_t();
   // Set the element's title attribute to show #title as a tooltip, if needed.
   if (isset($element['#title']) && $element['#title_display'] == 'attribute') {
     $element['#attributes']['title'] = $element['#title'];

modules/simpletest/tests/form.test

@@ -703,6 +703,12 @@ class FormsElementsLabelsTestCase extends DrupalWebTestCase {
 
     $elements = $this->xpath('//div[@id="form-test-textfield-title-suffix"]/preceding-sibling::div[contains(@class, \'form-item-form-textfield-test-title\')]');
     $this->assertTrue(isset($elements[0]), t("Properly places the #suffix element before the form item."));
+
+    // Check title attribute for radios and checkboxes.
+    $elements = $this->xpath('//div[@id="edit-form-checkboxes-title-attribute"]');
+    $this->assertEqual($elements[0]['title'], 'Checkboxes test' . ' (' . t('Required') . ')', 'Title attribute found.');
+    $elements = $this->xpath('//div[@id="edit-form-radios-title-attribute"]');
+    $this->assertEqual($elements[0]['title'], 'Radios test' . ' (' . t('Required') . ')', 'Title attribute found.');
   }
 }
 

modules/simpletest/tests/form_test.module

@@ -791,10 +791,31 @@ function form_label_test_form() {
     '#title' => t('Textfield test for invisible title'),
     '#title_display' => 'invisible',
   );
-  // Textfield test for title set not to display
+  // Textfield test for title set not to display.
   $form['form_textfield_test_title_no_show'] = array(
     '#type' => 'textfield',
   );
+  // Checkboxes & radios with title as attribute.
+  $form['form_checkboxes_title_attribute'] = array(
+    '#type' => 'checkboxes',
+    '#title' => 'Checkboxes test',
+    '#options' => array(
+      'first-checkbox' => 'First checkbox',
+      'second-checkbox' => 'Second checkbox',
+    ),
+    '#title_display' => 'attribute',
+    '#required' => TRUE,
+  );
+  $form['form_radios_title_attribute'] = array(
+    '#type' => 'radios',
+    '#title' => 'Radios test',
+    '#options' => array(
+      'first-radio' => 'First radio',
+      'second-radio' => 'Second radio',
+    ),
+    '#title_display' => 'attribute',
+    '#required' => TRUE,
+  );
 
   return $form;
 }