Issue #2226323 by kpv | danylevskyi: Fixed CompositeFormElementTrait causes...

Issue #2226323 by kpv | danylevskyi: Fixed CompositeFormElementTrait causes identical HTML ids for element and its wrapper.

core/lib/Drupal/Core/Render/Element/CompositeFormElementTrait.php

@@ -32,6 +32,7 @@ public static function preRenderCompositeFormElement($element) {
 
     if (isset($element['#title']) || isset($element['#description'])) {
       // @see #type 'fieldgroup'
+      $element['#attributes']['id'] = $element['#id'] . '--wrapper';
       $element['#theme_wrappers'][] = 'fieldset';
       $element['#attributes']['class'][] = 'fieldgroup';
       $element['#attributes']['class'][] = 'form-composite';

core/modules/system/src/Tests/Form/ElementTest.php

@@ -87,6 +87,21 @@ function testOptions() {
     }
   }
 
+  /**
+   * Tests wrapper ids for checkboxes and radios.
+   */
+  function testWrapperIds() {
+    $this->drupalGet('form-test/checkboxes-radios');
+
+    // Verify that wrapper id is different from element id.
+    foreach (array('checkboxes', 'radios') as $type) {
+      $element_ids = $this->xpath('//div[@id=:id]', array(':id' => 'edit-' . $type));
+      $wrapper_ids = $this->xpath('//fieldset[@id=:id]', array(':id' => 'edit-' . $type . '--wrapper'));
+      $this->assertTrue(count($element_ids) == 1, format_string('A single element id found for type %type', array('%type' => $type)));
+      $this->assertTrue(count($wrapper_ids) == 1, format_string('A single wrapper id found for type %type', array('%type' => $type)));
+    }
+  }
+
   /**
    * Tests button classes.
    */