diff --git a/core/modules/field/src/Tests/String/StringFieldTest.php b/core/modules/field/src/Tests/String/StringFieldTest.php
index f59d507..3114490 100644
--- a/core/modules/field/src/Tests/String/StringFieldTest.php
+++ b/core/modules/field/src/Tests/String/StringFieldTest.php
@@ -22,7 +22,7 @@ class StringFieldTest extends WebTestBase {
    *
    * @var array
    */
-  public static $modules = array('entity_test');
+  public static $modules = array('entity_test', 'file');
 
   /**
    * A user without any special permissions.
diff --git a/core/modules/text/src/Plugin/Field/FieldWidget/TextareaWithSummaryWidget.php b/core/modules/text/src/Plugin/Field/FieldWidget/TextareaWithSummaryWidget.php
index 8349f7a..d3c9cd3 100644
--- a/core/modules/text/src/Plugin/Field/FieldWidget/TextareaWithSummaryWidget.php
+++ b/core/modules/text/src/Plugin/Field/FieldWidget/TextareaWithSummaryWidget.php
@@ -92,7 +92,15 @@ function formElement(FieldItemListInterface $items, $delta, array $element, arra
    */
   public function errorElement(array $element, ConstraintViolationInterface $violation, array $form, FormStateInterface $form_state) {
     $element = parent::errorElement($element, $violation, $form, $form_state);
-    return ($element === FALSE) ? FALSE : $element[$violation->arrayPropertyPath[0]];
+    if ($element === FALSE) {
+      return FALSE;
+    }
+    elseif (isset($violation->arrayPropertyPath[0])) {
+      return $element[$violation->arrayPropertyPath[0]];
+    }
+    else {
+      return $element;
+    }
   }
 
 }
diff --git a/core/modules/text/src/Tests/TextFieldTest.php b/core/modules/text/src/Tests/TextFieldTest.php
index a22bc5b..a1c9ec3 100644
--- a/core/modules/text/src/Tests/TextFieldTest.php
+++ b/core/modules/text/src/Tests/TextFieldTest.php
@@ -68,6 +68,65 @@ function testTextFieldValidation() {
   }
 
   /**
+   * Test required long text with file upload.
+   */
+  function testRequiredLongTextWithFileUpload() {
+    // Create a text field.
+    $text_field_name = 'text_long';
+    $field_storage = entity_create('field_storage_config', array(
+      'field_name' => $text_field_name,
+      'entity_type' => 'entity_test',
+      'type' => 'text_with_summary',
+    ));
+    $field_storage->save();
+    entity_create('field_config', array(
+      'field_storage' => $field_storage,
+      'bundle' => 'entity_test',
+      'label' => $this->randomMachineName() . '_label',
+      'required' => TRUE,
+    ))->save();
+
+    // Create a file field.
+    $file_field_name = 'file_field';
+    $field_storage = entity_create('field_storage_config', array(
+      'field_name' => $file_field_name,
+      'entity_type' => 'entity_test',
+      'type' => 'file'
+    ));
+    $field_storage->save();
+    entity_create('field_config', array(
+      'field_storage' => $field_storage,
+      'bundle' => 'entity_test',
+      'label' => $this->randomMachineName() . '_label',
+    ))->save();
+
+    entity_get_form_display('entity_test', 'entity_test', 'default')
+      ->setComponent($text_field_name, array(
+        'type' => 'text_textarea_with_summary',
+      ))
+      ->setComponent($file_field_name, array(
+        'type' => 'file_generic',
+      ))
+      ->save();
+    entity_get_display('entity_test', 'entity_test', 'full')
+      ->setComponent($text_field_name)
+      ->setComponent($file_field_name)
+      ->save();
+
+    $test_file = current($this->drupalGetTestFiles('text'));
+    $edit['files[file_field_0]'] = drupal_realpath($test_file->uri);
+    $this->drupalPostForm('entity_test/add', $edit, 'Upload');
+    $this->assertResponse(200);
+    $edit = array(
+      'text_long[0][value]' => 'Long text'
+    );
+    $this->drupalPostForm(NULL, $edit, 'Save');
+    $this->assertResponse(200);
+    $this->drupalGet('entity_test/1');
+    $this->assertText('Long text');
+  }
+
+  /**
    * Test widgets.
    */
   function testTextfieldWidgets() {