Issue #2319719 by Tim Bozeman, pcambra, undertext, bojanz: Fixed Widget...

Issue #2319719 by Tim Bozeman, pcambra, undertext, bojanz: Fixed Widget validation crashes on ItemList violations.

core/lib/Drupal/Core/Field/WidgetBase.php

@@ -406,10 +406,6 @@ public function flagErrors(FieldItemListInterface $items, ConstraintViolationLis
           // Separate violations by delta.
           $property_path = explode('.', $violation->getPropertyPath());
           $delta = array_shift($property_path);
-          // Violations at the ItemList level are not associated to any delta,
-          // we file them under $delta NULL.
-          $delta = is_numeric($delta) ? $delta : NULL;
-
           $violations_by_delta[$delta][] = $violation;
           $violation->arrayPropertyPath = $property_path;
         }
@@ -419,7 +415,7 @@ public function flagErrors(FieldItemListInterface $items, ConstraintViolationLis
           // Pass violations to the main element:
           // - if this is a multiple-value widget,
           // - or if the violations are at the ItemList level.
-          if ($handles_multiple || $delta === NULL) {
+          if ($handles_multiple || !is_numeric($delta)) {
             $delta_element = $element;
           }
           // Otherwise, pass errors by delta to the corresponding sub-element.

core/modules/system/src/Tests/Entity/FieldWidgetConstraintValidatorTest.php

+<?php
+
+/**
+ * @file
+ * Contains Drupal\system\Tests\Entity\FieldWidgetConstraintValidatorTest.
+ */
+
+namespace Drupal\system\Tests\Entity;
+
+use Drupal\Core\Form\FormState;
+use Drupal\simpletest\KernelTestBase;
+use Drupal\system\Tests\TypedData;
+
+/**
+ * Tests validation constraints for FieldWidgetConstraintValidatorTest.
+ *
+ * @group Entity
+ */
+class FieldWidgetConstraintValidatorTest extends KernelTestBase {
+
+  public static $modules = array('entity', 'entity_test', 'field', 'user');
+
+  /**
+   * Tests widget constraint validation.
+   */
+  public function testValidation() {
+    $entity_type = 'entity_test_constraint_violation';
+    $entity = entity_create($entity_type, array('id' => 1, 'revision_id' => 1));
+    $display = entity_get_form_display($entity_type, $entity_type, 'default');
+    $form = array();
+    $form_state = new FormState();
+    $display->buildForm($entity, $form, $form_state);
+
+    // Pretend the form has been built.
+    $form_state['build_info']['callback_object'] = \Drupal::entityManager()->getFormObject($entity_type, 'default');
+    \Drupal::formBuilder()->prepareForm('field_test_entity_form', $form, $form_state);
+    \Drupal::formBuilder()->processForm('field_test_entity_form', $form, $form_state);
+
+    // Validate the field constraint.
+    $display->validateFormValues($entity, $form, $form_state);
+
+    $errors = $form_state->getErrors();
+    $this->assertEqual($errors['name'], 'Widget constraint has failed.', 'Constraint violation is generated correctly');
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Entity/EntityTestConstraintViolation.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\entity_test\Entity\EntityTestConstraintViolation.
+ */
+
+namespace Drupal\entity_test\Entity;
+
+use Drupal\Core\Entity\EntityTypeInterface;
+
+/**
+ * Defines the test entity class for testing entity constraint violations.
+ *
+ * @ContentEntityType(
+ *   id = "entity_test_constraint_violation",
+ *   label = @Translation("Test entity constraint violation"),
+ *   controllers = {
+ *     "form" = {
+ *       "default" = "Drupal\entity_test\EntityTestForm"
+ *     }
+ *   },
+ *   base_table = "entity_test",
+ *   fieldable = TRUE,
+ *   persistent_cache = FALSE,
+ *   entity_keys = {
+ *     "id" = "id",
+ *     "uuid" = "uuid",
+ *     "bundle" = "type",
+ *     "label" = "name"
+ *   }
+ * )
+ */
+class EntityTestConstraintViolation extends EntityTest {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
+    $fields = parent::baseFieldDefinitions($entity_type);
+
+    $fields['name']->setDisplayOptions('form', array(
+      'type' => 'string',
+      'weight' => 0,
+    ));
+    $fields['name']->addConstraint('FieldWidgetConstraint', array());
+
+    return $fields;
+  }
+
+}

core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/FieldWidgetConstraint.php

+<?php
+/**
+ * @file
+ * Contains \Drupal\entity_test\Plugin\Validation\Constraint\FieldWidgetConstraint.
+ */
+
+namespace Drupal\entity_test\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+
+/**
+ * Supports validating widget constraints.
+ *
+ * @Plugin(
+ *   id = "FieldWidgetConstraint",
+ *   label = @Translation("Field widget constraint.")
+ * )
+ */
+class FieldWidgetConstraint extends Constraint {
+
+  public $message = 'Widget constraint has failed.';
+
+}

core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/FieldWidgetConstraintValidator.php

+<?php
+/**
+ * @file
+ * Contains \Drupal\entity_test\Plugin\Validation\Constraint\FieldWidgetConstraintValidator.
+ */
+
+namespace Drupal\entity_test\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\ConstraintValidator;
+
+/**
+ * Validates the FieldWidgetConstraint constraint.
+ */
+class FieldWidgetConstraintValidator extends ConstraintValidator {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validate($field_item, Constraint $constraint) {
+    $this->context->addViolation($constraint->message);
+  }
+
+}