Issue #2075095 by yched, amateescu: Widget / Formatter methods signatures needlessly complex.

core/modules/datetime/lib/Drupal/datetime/Plugin/field/formatter/DatetimeDefaultFormatter.php

@@ -11,7 +11,6 @@
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Datetime\Date;
 use Drupal\Core\Datetime\DrupalDateTime;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityStorageControllerInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
@@ -95,7 +94,7 @@ public static function create(ContainerInterface $container, array $configuratio
   /**
    * {@inheritdoc}
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
 
     $elements = array();
 

core/modules/datetime/lib/Drupal/datetime/Plugin/field/formatter/DatetimePlainFormatter.php

@@ -10,7 +10,6 @@
 use Drupal\field\Annotation\FieldFormatter;
 use Drupal\Core\Annotation\Translation;
 use Drupal\field\Plugin\Type\Formatter\FormatterBase;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\Core\Datetime\DrupalDateTime;
 
@@ -30,7 +29,7 @@ class DateTimePlainFormatter extends FormatterBase {
   /**
    * {@inheritdoc}
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
 
     $elements = array();
 

core/modules/datetime/lib/Drupal/datetime/Plugin/field/widget/DatetimeDatelistWidget.php

@@ -9,13 +9,9 @@
 use Drupal\field\Annotation\FieldWidget;
 use Drupal\Core\Annotation\Translation;
 use Drupal\field\Plugin\Type\Widget\WidgetBase;
-use Drupal\Component\Plugin\Discovery\DiscoveryInterface;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
-use Drupal\field\Plugin\PluginSettingsBase;
 use Drupal\field\FieldInstanceInterface;
-use Drupal\Core\Datetime\DrupalDateTime;
 use Drupal\datetime\DateHelper;
 
 /**
@@ -62,7 +58,7 @@ public function defaultValueFunction() {
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldInterface $items, $delta, array $element, array &$form, array &$form_state) {
     $date_order = $this->getSetting('date_order');
     $time_type = $this->getSetting('time_type');
     $increment = $this->getSetting('increment');

core/modules/datetime/lib/Drupal/datetime/Plugin/field/widget/DatetimeDefaultWidget.php

@@ -9,13 +9,9 @@
 use Drupal\field\Annotation\FieldWidget;
 use Drupal\Core\Annotation\Translation;
 use Drupal\field\Plugin\Type\Widget\WidgetBase;
-use Drupal\Component\Plugin\Discovery\DiscoveryInterface;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
-use Drupal\field\Plugin\PluginSettingsBase;
 use Drupal\field\FieldInstanceInterface;
-use Drupal\Core\Datetime\DrupalDateTime;
 
 /**
  * Plugin implementation of the 'datetime_default' widget.
@@ -66,7 +62,7 @@ public function defaultValueFunction() {
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldInterface $items, $delta, array $element, array &$form, array &$form_state) {
     $format_type = datetime_default_format_type();
 
     // We are nesting some sub-elements inside the parent, so we need a wrapper.

core/modules/email/lib/Drupal/email/Plugin/field/formatter/MailToFormatter.php

@@ -10,7 +10,6 @@
 use Drupal\field\Annotation\FieldFormatter;
 use Drupal\Core\Annotation\Translation;
 use Drupal\field\Plugin\Type\Formatter\FormatterBase;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 
 /**
@@ -29,7 +28,7 @@ class MailToFormatter extends FormatterBase {
   /**
    * Implements Drupal\field\Plugin\Type\Formatter\FormatterInterface::viewElements().
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
     $elements = array();
 
     foreach ($items as $delta => $item) {

core/modules/email/lib/Drupal/email/Plugin/field/widget/EmailDefaultWidget.php

@@ -61,7 +61,7 @@ public function settingsSummary() {
   /**
    * Implements Drupal\field\Plugin\Type\Widget\WidgetInterface::formElement().
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldInterface $items, $delta, array $element, array &$form, array &$form_state) {
     $element['value'] = $element + array(
       '#type' => 'email',
       '#default_value' => isset($items[$delta]->value) ? $items[$delta]->value : NULL,

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceEntityFormatter.php

@@ -9,7 +9,6 @@
 
 use Drupal\field\Annotation\FieldFormatter;
 use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\entity_reference\RecursiveRenderingException;
 use Drupal\entity_reference\Plugin\field\formatter\EntityReferenceFormatterBase;
@@ -79,7 +78,7 @@ public function settingsSummary() {
   /**
    * {@inheritdoc}
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
     $view_mode = $this->getSetting('view_mode');
     $links = $this->getSetting('links');
 
@@ -96,13 +95,13 @@ public function viewElements(EntityInterface $entity, $langcode, FieldInterface
       static $depth = 0;
       $depth++;
       if ($depth > 20) {
-        throw new RecursiveRenderingException(format_string('Recursive rendering detected when rendering entity @entity_type(@entity_id). Aborting rendering.', array('@entity_type' => $entity_type, '@entity_id' => $item->target_id)));
+        throw new RecursiveRenderingException(format_string('Recursive rendering detected when rendering entity @entity_type(@entity_id). Aborting rendering.', array('@entity_type' => $item->entity->entityType(), '@entity_id' => $item->target_id)));
       }
 
       if (!empty($item->target_id)) {
         $entity = clone $item->entity;
         unset($entity->content);
-        $elements[$delta] = entity_view($entity, $view_mode, $langcode);
+        $elements[$delta] = entity_view($entity, $view_mode, $item->getLangcode());
 
         if (empty($links) && isset($result[$delta][$target_type][$item->target_id]['links'])) {
           // Hide the element links.
@@ -111,11 +110,12 @@ public function viewElements(EntityInterface $entity, $langcode, FieldInterface
       }
       else {
         // This is an "auto_create" item.
-        $elements[$delta] = array('#markup' => $entity->label());
+        $elements[$delta] = array('#markup' => $item->entity->label());
       }
       $depth = 0;
     }
 
     return $elements;
   }
+
 }

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceFormatterBase.php

@@ -7,10 +7,6 @@
 
 namespace Drupal\entity_reference\Plugin\field\formatter;
 
-use Drupal\field\Annotation\FieldFormatter;
-use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Entity\EntityInterface;
-use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\field\Plugin\Type\Formatter\FormatterBase;
 
 /**
@@ -25,13 +21,13 @@ abstract class EntityReferenceFormatterBase extends FormatterBase {
    * values, as other may want to act on those values, even if they can
    * not be accessed.
    */
-  public function prepareView(array $entities, $langcode, array $items) {
+  public function prepareView(array $entities_items) {
     $target_ids = array();
     $revision_ids = array();
 
     // Collect every possible entity attached to any of the entities.
-    foreach ($entities as $id => $entity) {
-      foreach ($items[$id] as $item) {
+    foreach ($entities_items as $items) {
+      foreach ($items as $item) {
         if (!empty($item->revision_id)) {
           $revision_ids[] = $item->revision_id;
         }
@@ -52,31 +48,30 @@ public function prepareView(array $entities, $langcode, array $items) {
     if ($revision_ids) {
       // We need to load the revisions one by-one.
       foreach ($revision_ids as $revision_id) {
-        $entity = entity_revision_load($target_type, $revision_id);
+        $target_entity = entity_revision_load($target_type, $revision_id);
         // Use the revision ID in the key.
-        $identifier = $entity->id() . ':' . $revision_id;
-        $target_entities[$identifier] = $entity;
+        $identifier = $target_entity->id() . ':' . $revision_id;
+        $target_entities[$identifier] = $target_entity;
       }
     }
 
     // Iterate through the fieldable entities again to attach the loaded data.
-    foreach ($entities as $id => $entity) {
+    foreach ($entities_items as $items) {
       $rekey = FALSE;
-      foreach ($items[$id] as $delta => $item) {
+      foreach ($items as $item) {
         // If we have a revision ID, the key uses it as well.
         $identifier = !empty($item->revision_id) ? $item->target_id . ':' . $item->revision_id : $item->target_id;
         if ($item->target_id !== 0) {
           if (!isset($target_entities[$identifier])) {
-            // The entity no longer exists, so remove the key.
+            // The entity no longer exists, so empty the item.
+            $item->setValue(NULL);
             $rekey = TRUE;
-            unset($items[$id][$delta]);
             continue;
           }
 
-          $entity = $target_entities[$identifier];
-          $item->entity = $entity;
+          $item->entity = $target_entities[$identifier];
 
-          if (!$entity->access('view')) {
+          if (!$item->entity->access('view')) {
             continue;
           }
         }
@@ -88,10 +83,11 @@ public function prepareView(array $entities, $langcode, array $items) {
         $item->access = TRUE;
       }
 
+      // Rekey the items array if needed.
       if ($rekey) {
-        // Rekey the items array.
-        $items[$id] = array_values($items[$id]);
+        $items->filterEmptyValues();
       }
     }
   }
+
 }

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceIdFormatter.php

@@ -9,7 +9,6 @@
 
 use Drupal\field\Annotation\FieldFormatter;
 use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\entity_reference\Plugin\field\formatter\EntityReferenceFormatterBase;
 
@@ -30,7 +29,7 @@ class EntityReferenceIdFormatter extends EntityReferenceFormatterBase {
   /**
    * Overrides \Drupal\entity_reference\Plugin\field\formatter\EntityReferenceFormatterBase::viewElements().
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
     $elements = array();
 
     foreach ($items as $delta => $item) {

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceLabelFormatter.php

@@ -9,7 +9,6 @@
 
 use Drupal\field\Annotation\FieldFormatter;
 use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\entity_reference\Plugin\field\formatter\EntityReferenceFormatterBase;
 
@@ -55,7 +54,7 @@ public function settingsSummary() {
   /**
    * {@inheritdoc}
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function viewElements(FieldInterface $items) {
     $elements = array();
 
     foreach ($items as $delta => $item) {
@@ -83,4 +82,5 @@ public function viewElements(EntityInterface $entity, $langcode, FieldInterface
 
     return $elements;
   }
+
 }

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/widget/AutocompleteWidget.php

@@ -40,7 +40,7 @@ class AutocompleteWidget extends AutocompleteWidgetBase {
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldInterface $items, $delta, array $element, array &$form, array &$form_state) {
     // We let the Field API handles multiple values for us, only take care of
     // the one matching our delta.
     if (isset($items[$delta])) {
@@ -50,7 +50,7 @@ public function formElement(FieldInterface $items, $delta, array $element, $lang
       $items->setValue(array());
     }
 
-    return parent::formElement($items, $delta, $element, $langcode, $form, $form_state);
+    return parent::formElement($items, $delta, $element, $form, $form_state);
   }
 
   /**

core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/widget/AutocompleteWidgetBase.php

@@ -70,9 +70,10 @@ public function settingsSummary() {
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldInterface $items, $delta, array $element, array &$form, array &$form_state) {
     global $user;
-    $entity = $element['#entity'];
+
+    $entity = $items->getEntity();
 
     // Prepare the autocomplete path.
     $autocomplete_path = $this->getSetting('autocomplete_path');

core/modules/field/field.api.php

@@ -198,10 +198,8 @@ function hook_field_widget_info_alter(array &$info) {
  *   - form: The form structure to which widgets are being attached. This may be
  *     a full form structure, or a sub-element of a larger form.
  *   - widget: The widget plugin instance.
- *   - field_definition: The field definition.
- *   - entity: The entity.
- *   - langcode: The language associated with $items.
- *   - items: Array of default values for this field.
+ *   - items: The field values, as a \Drupal\Core\Entity\Field\FieldInterface
+ *     object.
  *   - delta: The order of this item in the array of subelements (0, 1, 2, etc).
  *   - default: A boolean indicating whether the form is being shown as a dummy
  *     form to set default values.
@@ -211,7 +209,8 @@ function hook_field_widget_info_alter(array &$info) {
  */
 function hook_field_widget_form_alter(&$element, &$form_state, $context) {
   // Add a css class to widget form elements for all fields of type mytype.
-  if ($context['field']['type'] == 'mytype') {
+  $field_definition = $context['items']->getFieldDefinition();
+  if ($field_definition->getFieldType() == 'mytype') {
     // Be sure not to overwrite existing attributes.
     $element['#attributes']['class'][] = 'myclass';
   }

core/modules/field/field.attach.inc

@@ -123,7 +123,7 @@ function field_invoke_method($method, $target_function, EntityInterface $entity,
         $items = $entity->getTranslation($langcode)->get($field_name);
         $items->filterEmptyValues();
 
-        $result = $target->$method($entity, $langcode, $items, $a, $b);
+        $result = $target->$method($items, $a, $b);
 
         if (isset($result)) {
           // For methods with array results, we merge results together.
@@ -187,7 +187,6 @@ function field_invoke_method_multiple($method, $target_function, array $entities
   $options += $default_options;
 
   $instances = array();
-  $grouped_entities = array();
   $grouped_items = array();
   $grouped_targets = array();
   $return = array();
@@ -224,8 +223,7 @@ function field_invoke_method_multiple($method, $target_function, array $entities
         $langcode = !empty($options['langcode'][$id]) ? $options['langcode'][$id] : $options['langcode'];
         $langcodes = _field_language_suggestion($available_langcodes, $langcode, $field_name);
         foreach ($langcodes as $langcode) {
-          // Group the entities and items corresponding to the current field.
-          $grouped_entities[$instance_id][$langcode][$id] = $entities[$id];
+          // Group the items corresponding to the current field.
           $items = $entity->getTranslation($langcode)->get($field_name);
           $items->filterEmptyValues();
           $grouped_items[$instance_id][$langcode][$id] = $items;
@@ -238,12 +236,9 @@ function field_invoke_method_multiple($method, $target_function, array $entities
 
   // For each instance, invoke the method and collect results.
   foreach ($instances as $instance_id => $instance) {
-    $field_name = $instance['field_name'];
-
     // Iterate over all the field translations.
     foreach ($grouped_items[$instance_id] as $langcode => $items) {
-      $entities = $grouped_entities[$instance_id][$langcode];
-      $results = $grouped_targets[$instance_id]->$method($entities, $langcode, $items, $a, $b);
+      $results = $grouped_targets[$instance_id]->$method($items, $a, $b);
 
       if (isset($results)) {
         // Collect results by entity.

core/modules/field/field.module

@@ -697,9 +697,8 @@ function field_view_field(EntityInterface $entity, $field_name, $display_options
 
     // Invoke the formatter's prepareView() and view() methods.
     $items = $entity->getTranslation($display_langcode)->get($field_name);
-    $id = $entity->id();
-    $formatter->prepareView(array($id => $entity), $display_langcode, array($id => $items));
-    $result = $formatter->view($entity, $display_langcode, $items);
+    $formatter->prepareView(array($entity->id() => $items));
+    $result = $formatter->view($items);
 
     // Invoke hook_field_attach_view_alter() to let other modules alter the
     // renderable array, as in a full field_attach_view() execution.

core/modules/field/field.multilingual.inc

@@ -34,7 +34,7 @@
  * is attached to supports translation.
  *
  * By default, field_invoke_method() processes a field in all available
- * languages, unless they are given a language code suggestion. Based on that
+ * languages, unless it is given a language code suggestion. Based on that
  * suggestion, _field_language_suggestion() determines the languages to act on.
  *
  * Most field_attach_*() functions act on all available language codes, except

core/modules/field/lib/Drupal/field/Plugin/Type/FieldType/ConfigField.php

@@ -78,11 +78,10 @@ protected function getDefaultValue() {
    */
   public function defaultValuesForm(array &$form, array &$form_state) {
     if (empty($this->getFieldDefinition()->default_value_function)) {
-      $widget = $this->defaultValueWidget($form_state);
-
       // Place the input in a separate place in the submitted values tree.
+      $widget = $this->defaultValueWidget($form_state);
       $element = array('#parents' => array('default_value_input'));
-      $element += $widget->form($this->getEntity(), $this->getLangcode(), $this, $element, $form_state);
+      $element += $widget->form($this, $element, $form_state);
 
       return $element;
     }
@@ -92,12 +91,9 @@ public function defaultValuesForm(array &$form, array &$form_state) {
    * {@inheritdoc}
    */
   public function defaultValuesFormValidate(array $element, array &$form, array &$form_state) {
-    $entity = $this->getEntity();
-    $langcode = $this->getLangcode();
-
     // Extract the submitted value, and validate it.
     $widget = $this->defaultValueWidget($form_state);
-    $widget->extractFormValues($entity, $langcode, $this, $element, $form_state);
+    $widget->extractFormValues($this, $element, $form_state);
     $violations = $this->validate();
 
     if (count($violations)) {
@@ -108,7 +104,7 @@ public function defaultValuesFormValidate(array $element, array &$form, array &$
       field_form_set_state($element['#parents'], $field_name, $form_state, $field_state);
 
       // Assign reported errors to the correct form element.
-      $widget->flagErrors($entity, $langcode, $this, $element, $form_state);
+      $widget->flagErrors($this, $element, $form_state);
     }
   }
 
@@ -118,7 +114,7 @@ public function defaultValuesFormValidate(array $element, array &$form, array &$
   public function defaultValuesFormSubmit(array $element, array &$form, array &$form_state) {
     // Extract the submitted value, and return it as an array.
     $widget = $this->defaultValueWidget($form_state);
-    $widget->extractFormValues($this->getEntity(), $this->getLangcode(), $this, $element, $form_state);
+    $widget->extractFormValues($this, $element, $form_state);
     return $this->getValue();
   }
 

core/modules/field/lib/Drupal/field/Plugin/Type/Formatter/FormatterBase.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\field\Plugin\Type\Formatter;
 
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\field\FieldInstanceInterface;
@@ -74,11 +73,12 @@ public function __construct($plugin_id, array $plugin_definition, FieldDefinitio
   /**
    * {@inheritdoc}
    */
-  public function view(EntityInterface $entity, $langcode, FieldInterface $items) {
+  public function view(FieldInterface $items) {
     $addition = array();
 
-    $elements = $this->viewElements($entity, $langcode, $items);
+    $elements = $this->viewElements($items);
     if ($elements) {
+      $entity = $items->getEntity();
       $entity_type = $entity->entityType();
       $field_name = $this->fieldDefinition->getFieldName();
       $info = array(
@@ -87,7 +87,7 @@ public function view(EntityInterface $entity, $langcode, FieldInterface $items)
         '#access' => $this->checkFieldAccess('view', $entity),
         '#label_display' => $this->label,
         '#view_mode' => $this->viewMode,
-        '#language' => $langcode,
+        '#language' => $items->getLangcode(),
         '#field_name' => $field_name,
         '#field_type' => $this->fieldDefinition->getFieldType(),
         '#field_translatable' => $this->fieldDefinition->isFieldTranslatable(),
@@ -121,7 +121,7 @@ public function settingsSummary() {
   /**
    * {@inheritdoc}
    */
-  public function prepareView(array $entities, $langcode, array $items) { }
+  public function prepareView(array $entities_items) { }
 
   /**
    * Returns whether the currently logged in user has access to the field.

core/modules/field/lib/Drupal/field/Plugin/Type/Formatter/FormatterInterface.php

@@ -7,7 +7,6 @@
 
 namespace Drupal\field\Plugin\Type\Formatter;
 
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\field\Plugin\PluginSettingsInterface;
 
@@ -61,45 +60,33 @@ public function settingsSummary();
    * Changes or additions to field values are done by alterings the $items
    * parameter by reference.
    *
-   * @param array $entities
-   *   Array of entities being displayed, keyed by entity ID.
-   * @param string $langcode
-   *   The language the field values are to be shown in. If no language is
-   *   provided the current language is used.
-   * @param array $items
-   *   Array of field values for the entities, keyed by entity ID.
+   * @param array $entities_items
+   *   Array of field values (Drupal\Core\Entity\Field\FieldInterface), keyed by
+   *   entity ID.
    */
-  public function prepareView(array $entities, $langcode, array $items);
+  public function prepareView(array $entities_items);
 
   /**
    * Builds a renderable array for one field on one entity instance.
    *
-   * @param Drupal\Core\Entity\EntityInterface $entity
-   *   The entity being displayed.
-   * @param string $langcode
-   *   The language associated with $items.
    * @param Drupal\Core\Entity\Field\FieldInterface $items
-   *   The field value for the entity for the language.
+   *   The field values to be rendered.
    *
    * @return array
    *   A renderable array for a themed field with its label and all its values.
    */
-  public function view(EntityInterface $entity, $langcode, FieldInterface $items);
+  public function view(FieldInterface $items);
 
   /**
    * Builds a renderable array for a field value.
    *
-   * @param Drupal\Core\Entity\EntityInterface $entity
-   *   The entity being displayed.
-   * @param string $langcode
-   *   The language associated with $items.
-   * @param array $items
-   *   Array of values for this field.
+   * @param Drupal\Core\Entity\Field\FieldInterface $items
+   *   The field values to be rendered.
    *
    * @return array
    *   A renderable array for $items, as an array of child elements keyed by
    *   numeric indexes starting from 0.
    */
-  public function viewElements(EntityInterface $entity, $langcode, FieldInterface $items);
+  public function viewElements(FieldInterface $items);
 
 }

core/modules/field/lib/Drupal/field/Plugin/Type/Widget/WidgetBase.php

@@ -8,7 +8,6 @@
 namespace Drupal\field\Plugin\Type\Widget;
 
 use Drupal\Component\Utility\NestedArray;
-use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Entity\Field\FieldInterface;
 use Drupal\field\FieldInstanceInterface;
@@ -56,7 +55,7 @@ public function __construct($plugin_id, array $plugin_definition, FieldDefinitio
   /**
    * {@inheritdoc}
    */
-  public function form(EntityInterface $entity, $langcode, FieldInterface $items, array &$form, array &$form_state, $get_delta = NULL) {
+  public function form(FieldInterface $items, array &$form, array &$form_state, $get_delta = NULL) {
     $field_name = $this->fieldDefinition->getFieldName();
     $parents = $form['#parents'];
 
@@ -83,7 +82,7 @@ public function form(EntityInterface $entity, $langcode, FieldInterface $items,
         '#title' => check_plain($this->fieldDefinition->getFieldLabel()),
         '#description' => field_filter_xss(\Drupal::token()->replace($this->fieldDefinition->getFieldDescription())),
       );
-      $element = $this->formSingleElement($entity, $items, $delta, $langcode, $element, $form, $form_state);
+      $element = $this->formSingleElement($items, $delta, $element, $form, $form_state);
 
       if ($element) {
         if (isset($get_delta)) {
@@ -102,7 +101,7 @@ public function form(EntityInterface $entity, $langcode, FieldInterface $items,