updated core and modules

core/modules/datetime/config/schema/datetime.schema.yml

@@ -47,10 +47,8 @@ field.formatter.settings.datetime_custom:
   label: 'Datetime custom display format settings'
   mapping:
     date_format:
-      type: string
+      type: date_format
       label: 'Date/time format'
-      translatable: true
-      translation context: 'PHP date format'
 
 field.formatter.settings.datetime_time_ago:
   type: mapping

core/modules/datetime/datetime.info.yml

@@ -7,8 +7,8 @@ package: Field types
 dependencies:
   - field
 
-# Information added by Drupal.org packaging script on 2016-08-03
-version: '8.1.8'
+# Information added by Drupal.org packaging script on 2017-08-16
+version: '8.3.7'
 core: '8.x'
 project: 'drupal'
-datestamp: 1470233790
+datestamp: 1502903957

core/modules/datetime/datetime.module

@@ -30,16 +30,16 @@ function datetime_help($route_name, RouteMatchInterface $route_match) {
     case 'help.page.datetime':
       $output = '';
       $output .= '<h3>' . t('About') . '</h3>';
-      $output .= '<p>' . t('The Datetime module provides a Date field that stores dates and times. It also provides the Form API elements <em>datetime</em> and <em>datelist</em> for use in programming modules. See the <a href=":field">Field module help</a> and the <a href=":field_ui">Field UI module help</a> pages for general information on fields and how to create and manage them. For more information, see the <a href=":datetime_do">online documentation for the Datetime module</a>.', array(':field' => \Drupal::url('help.page', array('name' => 'field')), ':field_ui' => (\Drupal::moduleHandler()->moduleExists('field_ui')) ? \Drupal::url('help.page', array('name' => 'field_ui')) : '#', ':datetime_do' => 'https://www.drupal.org/documentation/modules/datetime')) . '</p>';
+      $output .= '<p>' . t('The Datetime module provides a Date field that stores dates and times. It also provides the Form API elements <em>datetime</em> and <em>datelist</em> for use in programming modules. See the <a href=":field">Field module help</a> and the <a href=":field_ui">Field UI module help</a> pages for general information on fields and how to create and manage them. For more information, see the <a href=":datetime_do">online documentation for the Datetime module</a>.', [':field' => \Drupal::url('help.page', ['name' => 'field']), ':field_ui' => (\Drupal::moduleHandler()->moduleExists('field_ui')) ? \Drupal::url('help.page', ['name' => 'field_ui']) : '#', ':datetime_do' => 'https://www.drupal.org/documentation/modules/datetime']) . '</p>';
       $output .= '<h3>' . t('Uses') . '</h3>';
       $output .= '<dl>';
       $output .= '<dt>' . t('Managing and displaying date fields') . '</dt>';
-      $output .= '<dd>' . t('The <em>settings</em> and the <em>display</em> of the Date field can be configured separately. See the <a href=":field_ui">Field UI help</a> for more information on how to manage fields and their display.', array(':field_ui' => (\Drupal::moduleHandler()->moduleExists('field_ui')) ? \Drupal::url('help.page', array('name' => 'field_ui')) : '#')) . '</dd>';
+      $output .= '<dd>' . t('The <em>settings</em> and the <em>display</em> of the Date field can be configured separately. See the <a href=":field_ui">Field UI help</a> for more information on how to manage fields and their display.', [':field_ui' => (\Drupal::moduleHandler()->moduleExists('field_ui')) ? \Drupal::url('help.page', ['name' => 'field_ui']) : '#']) . '</dd>';
       $output .= '<dt>' . t('Displaying dates') . '</dt>';
-      $output .= '<dd>' . t('Dates can be displayed using the <em>Plain</em> or the <em>Default</em> formatter. The <em>Plain</em> formatter displays the date in the <a href="http://en.wikipedia.org/wiki/ISO_8601">ISO 8601</a> format. If you choose the <em>Default</em> formatter, you can choose a format from a predefined list that can be managed on the <a href=":date_format_list">Date and time formats</a> page.', array(':date_format_list' => \Drupal::url('entity.date_format.collection'))) . '</dd>';
+      $output .= '<dd>' . t('Dates can be displayed using the <em>Plain</em> or the <em>Default</em> formatter. The <em>Plain</em> formatter displays the date in the <a href="http://en.wikipedia.org/wiki/ISO_8601">ISO 8601</a> format. If you choose the <em>Default</em> formatter, you can choose a format from a predefined list that can be managed on the <a href=":date_format_list">Date and time formats</a> page.', [':date_format_list' => \Drupal::url('entity.date_format.collection')]) . '</dd>';
       $output .= '</dl>';
       return $output;
-    }
+  }
 }
 
 /**

core/modules/datetime/src/DateTimeComputed.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\datetime;
 
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
 use Drupal\Core\Datetime\DrupalDateTime;
 use Drupal\Core\TypedData\DataDefinitionInterface;
 use Drupal\Core\TypedData\TypedDataInterface;
@@ -40,14 +41,28 @@ class DateTimeComputed extends TypedData {
       return $this->date;
     }
 
+    /** @var \Drupal\Core\Field\FieldItemInterface $item */
     $item = $this->getParent();
     $value = $item->{($this->definition->getSetting('date source'))};
 
-    $storage_format = $item->getFieldDefinition()->getSetting('datetime_type') == 'date' ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
+    $datetime_type = $item->getFieldDefinition()->getSetting('datetime_type');
+    $storage_format = $datetime_type === DateTimeItem::DATETIME_TYPE_DATE ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
     try {
       $date = DrupalDateTime::createFromFormat($storage_format, $value, DATETIME_STORAGE_TIMEZONE);
       if ($date instanceof DrupalDateTime && !$date->hasErrors()) {
         $this->date = $date;
+        // If the format did not include an explicit time portion, then the
+        // time will be set from the current time instead. For consistency, we
+        // set the time to 12:00:00 UTC for date-only fields. This is used so
+        // that the local date portion is the same, across nearly all time
+        // zones.
+        // @see datetime_date_default_time()
+        // @see http://php.net/manual/en/datetime.createfromformat.php
+        // @todo Update comment and/or code per the chosen solution in
+        //   https://www.drupal.org/node/2830094
+        if ($datetime_type === DateTimeItem::DATETIME_TYPE_DATE) {
+          $this->date->setTime(12, 0, 0);
+        }
       }
     }
     catch (\Exception $e) {

core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeCustomFormatter.php

@@ -23,16 +23,16 @@ class DateTimeCustomFormatter extends DateTimeFormatterBase {
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'date_format' => DATETIME_DATETIME_STORAGE_FORMAT,
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
    * {@inheritdoc}
    */
   public function viewElements(FieldItemListInterface $items, $langcode) {
-    $elements = array();
+    $elements = [];
 
     foreach ($items as $delta => $item) {
       $output = '';
@@ -76,12 +76,12 @@ class DateTimeCustomFormatter extends DateTimeFormatterBase {
   public function settingsForm(array $form, FormStateInterface $form_state) {
     $form = parent::settingsForm($form, $form_state);
 
-    $form['date_format'] = array(
+    $form['date_format'] = [
       '#type' => 'textfield',
       '#title' => $this->t('Date/time format'),
       '#description' => $this->t('See <a href="http://php.net/manual/function.date.php" target="_blank">the documentation for PHP date formats</a>.'),
       '#default_value' => $this->getSetting('date_format'),
-    );
+    ];
 
     return $form;
   }

core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php

@@ -23,16 +23,16 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'format_type' => 'medium',
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
    * {@inheritdoc}
    */
   public function viewElements(FieldItemListInterface $items, $langcode) {
-    $elements = array();
+    $elements = [];
 
     foreach ($items as $delta => $item) {
       $output = '';
@@ -56,7 +56,7 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
       }
 
       // Display the date using theme datetime.
-      $elements[$delta] = array(
+      $elements[$delta] = [
         '#cache' => [
           'contexts' => [
             'timezone',
@@ -65,10 +65,10 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
         '#theme' => 'time',
         '#text' => $output,
         '#html' => FALSE,
-        '#attributes' => array(
+        '#attributes' => [
           'datetime' => $iso_date,
-        ),
-      );
+        ],
+      ];
       if (!empty($item->_attributes)) {
         $elements[$delta]['#attributes'] += $item->_attributes;
         // Unset field item attributes since they have been included in the
@@ -86,7 +86,7 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
    */
   protected function formatDate($date) {
     $format_type = $this->getSetting('format_type');
-    $timezone = $this->getSetting('timezone_override');
+    $timezone = $this->getSetting('timezone_override') ?: $date->getTimezone()->getName();
     return $this->dateFormatter->format($date->getTimestamp(), $format_type, '', $timezone != '' ? $timezone : NULL);
   }
 
@@ -100,17 +100,17 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
     $format_types = $this->dateFormatStorage->loadMultiple();
     $options = [];
     foreach ($format_types as $type => $type_info) {
-      $format = $this->dateFormatter->format($time->format('U'), $type);
+      $format = $this->dateFormatter->format($time->getTimestamp(), $type);
       $options[$type] = $type_info->label() . ' (' . $format . ')';
     }
 
-    $form['format_type'] = array(
+    $form['format_type'] = [
       '#type' => 'select',
       '#title' => t('Date format'),
       '#description' => t("Choose a format for displaying the date. Be sure to set a format appropriate for the field, i.e. omitting time for a field that only has a date."),
       '#options' => $options,
       '#default_value' => $this->getSetting('format_type'),
-    );
+    ];
 
     return $form;
   }
@@ -122,7 +122,7 @@ class DateTimeDefaultFormatter extends DateTimeFormatterBase {
     $summary = parent::settingsSummary();
 
     $date = new DrupalDateTime();
-    $summary[] = t('Format: @display', array('@display' => $this->formatDate($date, $this->getFormatSettings())));
+    $summary[] = t('Format: @display', ['@display' => $this->formatDate($date, $this->getFormatSettings())]);
 
     return $summary;
   }

core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php

@@ -9,6 +9,7 @@ use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Field\FormatterBase;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 
@@ -81,9 +82,9 @@ abstract class DateTimeFormatterBase extends FormatterBase implements ContainerF
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'timezone_override' => '',
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
@@ -92,13 +93,13 @@ abstract class DateTimeFormatterBase extends FormatterBase implements ContainerF
   public function settingsForm(array $form, FormStateInterface $form_state) {
     $form = parent::settingsForm($form, $form_state);
 
-    $form['timezone_override'] = array(
+    $form['timezone_override'] = [
       '#type' => 'select',
       '#title' => $this->t('Time zone override'),
       '#description' => $this->t('The time zone selected here will always be used'),
       '#options' => system_time_zones(TRUE),
       '#default_value' => $this->getSetting('timezone_override'),
-    );
+    ];
 
     return $form;
   }
@@ -110,7 +111,7 @@ abstract class DateTimeFormatterBase extends FormatterBase implements ContainerF
     $summary = parent::settingsSummary();
 
     if ($override = $this->getSetting('timezone_override')) {
-      $summary[] = $this->t('Time zone: @timezone', array('@timezone' => $override));
+      $summary[] = $this->t('Time zone: @timezone', ['@timezone' => $override]);
     }
 
     return $summary;
@@ -140,7 +141,14 @@ abstract class DateTimeFormatterBase extends FormatterBase implements ContainerF
    *   A DrupalDateTime object.
    */
   protected function setTimeZone(DrupalDateTime $date) {
-    $date->setTimeZone(timezone_open(drupal_get_user_timezone()));
+    if ($this->getFieldSetting('datetime_type') === DateTimeItem::DATETIME_TYPE_DATE) {
+      // A date without time has no timezone conversion.
+      $timezone = DATETIME_STORAGE_TIMEZONE;
+    }
+    else {
+      $timezone = drupal_get_user_timezone();
+    }
+    $date->setTimeZone(timezone_open($timezone));
   }
 
   /**

core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimePlainFormatter.php

@@ -3,6 +3,7 @@
 namespace Drupal\datetime\Plugin\Field\FieldFormatter;
 
 use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
 
 /**
  * Plugin implementation of the 'Plain' formatter for 'datetime' fields.
@@ -21,7 +22,7 @@ class DateTimePlainFormatter extends DateTimeFormatterBase {
    * {@inheritdoc}
    */
   public function viewElements(FieldItemListInterface $items, $langcode) {
-    $elements = array();
+    $elements = [];
 
     foreach ($items as $delta => $item) {
       $output = '';
@@ -33,8 +34,6 @@ class DateTimePlainFormatter extends DateTimeFormatterBase {
           // A date without time will pick up the current time, use the default.
           datetime_date_default_time($date);
         }
-        else {
-        }
         $this->setTimeZone($date);
 
         $output = $this->formatDate($date);
@@ -56,7 +55,7 @@ class DateTimePlainFormatter extends DateTimeFormatterBase {
    * {@inheritdoc}
    */
   protected function formatDate($date) {
-    $format = $this->getFieldSetting('datetime_type') == 'date' ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
+    $format = $this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
     $timezone = $this->getSetting('timezone_override');
     return $this->dateFormatter->format($date->getTimestamp(), 'custom', $format, $timezone != '' ? $timezone : NULL);
   }

core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeTimeAgoFormatter.php

@@ -74,11 +74,11 @@ class DateTimeTimeAgoFormatter extends FormatterBase implements ContainerFactory
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    $settings = array(
+    $settings = [
       'future_format' => '@interval hence',
       'past_format' => '@interval ago',
       'granularity' => 2,
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
 
     return $settings;
   }
@@ -104,7 +104,7 @@ class DateTimeTimeAgoFormatter extends FormatterBase implements ContainerFactory
    * {@inheritdoc}
    */
   public function viewElements(FieldItemListInterface $items, $langcode) {
-    $elements = array();
+    $elements = [];
 
     foreach ($items as $delta => $item) {
       $date = $item->date;
@@ -128,26 +128,26 @@ class DateTimeTimeAgoFormatter extends FormatterBase implements ContainerFactory
   public function settingsForm(array $form, FormStateInterface $form_state) {
     $form = parent::settingsForm($form, $form_state);
 
-    $form['future_format'] = array(
+    $form['future_format'] = [
       '#type' => 'textfield',
       '#title' => $this->t('Future format'),
       '#default_value' => $this->getSetting('future_format'),
       '#description' => $this->t('Use <em>@interval</em> where you want the formatted interval text to appear.'),
-    );
+    ];
 
-    $form['past_format'] = array(
+    $form['past_format'] = [
       '#type' => 'textfield',
       '#title' => $this->t('Past format'),
       '#default_value' => $this->getSetting('past_format'),
       '#description' => $this->t('Use <em>@interval</em> where you want the formatted interval text to appear.'),
-    );
+    ];
 
-    $form['granularity'] = array(
+    $form['granularity'] = [
       '#type' => 'number',
       '#title' => $this->t('Granularity'),
       '#default_value' => $this->getSetting('granularity'),
       '#description' => $this->t('How many time units should be shown in the formatted output.'),
-    );
+    ];
 
     return $form;
   }
@@ -160,8 +160,8 @@ class DateTimeTimeAgoFormatter extends FormatterBase implements ContainerFactory
 
     $future_date = new DrupalDateTime('1 year 1 month 1 week 1 day 1 hour 1 minute');
     $past_date = new DrupalDateTime('-1 year -1 month -1 week -1 day -1 hour -1 minute');
-    $summary[] = t('Future date: %display', array('%display' => $this->formatDate($future_date)));
-    $summary[] = t('Past date: %display', array('%display' => $this->formatDate($past_date)));
+    $summary[] = t('Future date: %display', ['%display' => $this->formatDate($future_date)]);
+    $summary[] = t('Past date: %display', ['%display' => $this->formatDate($past_date)]);
 
     return $summary;
   }

core/modules/datetime/src/Plugin/Field/FieldType/DateTimeFieldItemList.php

@@ -30,31 +30,31 @@ class DateTimeFieldItemList extends FieldItemList {
     if (empty($this->getFieldDefinition()->getDefaultValueCallback())) {
       $default_value = $this->getFieldDefinition()->getDefaultValueLiteral();
 
-      $element = array(
-        '#parents' => array('default_value_input'),
-        'default_date_type' => array(
+      $element = [
+        '#parents' => ['default_value_input'],
+        'default_date_type' => [
           '#type' => 'select',
           '#title' => t('Default date'),
           '#description' => t('Set a default value for this date.'),
           '#default_value' => isset($default_value[0]['default_date_type']) ? $default_value[0]['default_date_type'] : '',
-          '#options' => array(
+          '#options' => [
             static::DEFAULT_VALUE_NOW => t('Current date'),
             static::DEFAULT_VALUE_CUSTOM => t('Relative date'),
-          ),
+          ],
           '#empty_value' => '',
-        ),
-        'default_date' => array(
+        ],
+        'default_date' => [
           '#type' => 'textfield',
           '#title' => t('Relative default value'),
           '#description' => t("Describe a time by reference to the current day, like '+90 days' (90 days from the day the field is created) or '+1 Saturday' (the next Saturday). See <a href=\"http://php.net/manual/function.strtotime.php\">strtotime</a> for more details."),
           '#default_value' => (isset($default_value[0]['default_date_type']) && $default_value[0]['default_date_type'] == static::DEFAULT_VALUE_CUSTOM) ? $default_value[0]['default_date'] : '',
-          '#states' => array(
-            'visible' => array(
-              ':input[id="edit-default-value-input-default-date-type"]' => array('value' => static::DEFAULT_VALUE_CUSTOM),
-            )
-          )
-        )
-      );
+          '#states' => [
+            'visible' => [
+              ':input[id="edit-default-value-input-default-date-type"]' => ['value' => static::DEFAULT_VALUE_CUSTOM],
+            ]
+          ]
+        ]
+      ];
 
       return $element;
     }
@@ -65,7 +65,7 @@ class DateTimeFieldItemList extends FieldItemList {
    */
   public function defaultValuesFormValidate(array $element, array &$form, FormStateInterface $form_state) {
     if ($form_state->getValue(['default_value_input', 'default_date_type']) == static::DEFAULT_VALUE_CUSTOM) {
-      $is_strtotime = @strtotime($form_state->getValue(array('default_value_input', 'default_date')));
+      $is_strtotime = @strtotime($form_state->getValue(['default_value_input', 'default_date']));
       if (!$is_strtotime) {
         $form_state->setErrorByName('default_value_input][default_date', t('The relative date value entered is invalid.'));
       }
@@ -76,13 +76,13 @@ class DateTimeFieldItemList extends FieldItemList {
    * {@inheritdoc}
    */
   public function defaultValuesFormSubmit(array $element, array &$form, FormStateInterface $form_state) {
-    if ($form_state->getValue(array('default_value_input', 'default_date_type'))) {
-      if ($form_state->getValue(array('default_value_input', 'default_date_type')) == static::DEFAULT_VALUE_NOW) {
+    if ($form_state->getValue(['default_value_input', 'default_date_type'])) {
+      if ($form_state->getValue(['default_value_input', 'default_date_type']) == static::DEFAULT_VALUE_NOW) {
         $form_state->setValueForElement($element['default_date'], static::DEFAULT_VALUE_NOW);
       }
-      return array($form_state->getValue('default_value_input'));
+      return [$form_state->getValue('default_value_input')];
     }
-    return array();
+    return [];
   }
 
   /**
@@ -92,20 +92,28 @@ class DateTimeFieldItemList extends FieldItemList {
     $default_value = parent::processDefaultValue($default_value, $entity, $definition);
 
     if (isset($default_value[0]['default_date_type'])) {
-      // A default value should be in the format and timezone used for date
-      // storage.
-      $date = new DrupalDateTime($default_value[0]['default_date'], DATETIME_STORAGE_TIMEZONE);
-      $storage_format = $definition->getSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
-      $value = $date->format($storage_format);
+      if ($definition->getSetting('datetime_type') === DateTimeItem::DATETIME_TYPE_DATE) {
+        // A default date only value should be in the format used for date
+        // storage but in the user's local timezone.
+        $date = new DrupalDateTime($default_value[0]['default_date'], drupal_get_user_timezone());
+        $format = DATETIME_DATE_STORAGE_FORMAT;
+      }
+      else {
+        // A default date+time value should be in the format and timezone used
+        // for date storage.
+        $date = new DrupalDateTime($default_value[0]['default_date'], DATETIME_STORAGE_TIMEZONE);
+        $format = DATETIME_DATETIME_STORAGE_FORMAT;
+      }
+      $value = $date->format($format);
       // We only provide a default value for the first item, as do all fields.
       // Otherwise, there is no way to clear out unwanted values on multiple value
       // fields.
-      $default_value = array(
-        array(
+      $default_value = [
+        [
           'value' => $value,
           'date' => $date,
-        )
-      );
+        ]
+      ];
     }
     return $default_value;
   }

core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php

@@ -26,9 +26,9 @@ class DateTimeItem extends FieldItemBase {
    * {@inheritdoc}
    */
   public static function defaultStorageSettings() {
-    return array(
+    return [
       'datetime_type' => 'datetime',
-    ) + parent::defaultStorageSettings();
+    ] + parent::defaultStorageSettings();
   }
 
   /**
@@ -63,37 +63,37 @@ class DateTimeItem extends FieldItemBase {
    * {@inheritdoc}
    */
   public static function schema(FieldStorageDefinitionInterface $field_definition) {
-    return array(
-      'columns' => array(
-        'value' => array(
+    return [
+      'columns' => [
+        'value' => [
           'description' => 'The date value.',
           'type' => 'varchar',
           'length' => 20,
-        ),
-      ),
-      'indexes' => array(
-        'value' => array('value'),
-      ),
-    );
+        ],
+      ],
+      'indexes' => [
+        'value' => ['value'],
+      ],
+    ];
   }
 
   /**
    * {@inheritdoc}
    */
   public function storageSettingsForm(array &$form, FormStateInterface $form_state, $has_data) {
-    $element = array();
+    $element = [];
 
-    $element['datetime_type'] = array(
+    $element['datetime_type'] = [
       '#type' => 'select',
       '#title' => t('Date type'),
       '#description' => t('Choose the type of date to create.'),
       '#default_value' => $this->getSetting('datetime_type'),
-      '#options' => array(
+      '#options' => [
         static::DATETIME_TYPE_DATETIME => t('Date and time'),
         static::DATETIME_TYPE_DATE => t('Date only'),
-      ),
+      ],
       '#disabled' => $has_data,
-    );
+    ];
 
     return $element;
   }

core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeDatelistWidget.php

@@ -22,11 +22,11 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'increment' => '15',
       'date_order' => 'YMD',
       'time_type' => '24',
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
@@ -35,6 +35,9 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
   public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
     $element = parent::formElement($items, $delta, $element, $form, $form_state);
 
+    // Wrap all of the select elements with a fieldset.
+    $element['#theme_wrappers'][] = 'fieldset';
+
     $date_order = $this->getSetting('date_order');
 
     if ($this->getFieldSetting('datetime_type') == 'datetime') {
@@ -49,35 +52,35 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
     // Set up the date part order array.
     switch ($date_order) {
       case 'YMD':
-        $date_part_order = array('year', 'month', 'day');
+        $date_part_order = ['year', 'month', 'day'];
         break;
 
       case 'MDY':
-        $date_part_order = array('month', 'day', 'year');
+        $date_part_order = ['month', 'day', 'year'];
         break;
 
       case 'DMY':
-        $date_part_order = array('day', 'month', 'year');
+        $date_part_order = ['day', 'month', 'year'];
         break;
     }
     switch ($time_type) {
-       case '24':
-         $date_part_order = array_merge($date_part_order, array('hour', 'minute'));
-         break;
+      case '24':
+        $date_part_order = array_merge($date_part_order, ['hour', 'minute']);
+        break;
 
-       case '12':
-         $date_part_order = array_merge($date_part_order, array('hour', 'minute', 'ampm'));
-         break;
+      case '12':
+        $date_part_order = array_merge($date_part_order, ['hour', 'minute', 'ampm']);
+        break;
 
-       case 'none':
-         break;
+      case 'none':
+        break;
     }
 
-    $element['value'] = array(
+    $element['value'] = [
       '#type' => 'datelist',
       '#date_increment' => $increment,
       '#date_part_order' => $date_part_order,
-    ) + $element['value'];
+    ] + $element['value'];
 
     return $element;
   }
@@ -85,23 +88,23 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
   /**
    * {@inheritdoc}
    */
-  function settingsForm(array $form, FormStateInterface $form_state) {
+  public function settingsForm(array $form, FormStateInterface $form_state) {
     $element = parent::settingsForm($form, $form_state);
 
-    $element['date_order'] = array(
+    $element['date_order'] = [
       '#type' => 'select',
       '#title' => t('Date part order'),
       '#default_value' => $this->getSetting('date_order'),
-      '#options' => array('MDY' => t('Month/Day/Year'), 'DMY' => t('Day/Month/Year'), 'YMD' => t('Year/Month/Day')),
-    );
+      '#options' => ['MDY' => t('Month/Day/Year'), 'DMY' => t('Day/Month/Year'), 'YMD' => t('Year/Month/Day')],
+    ];
 
     if ($this->getFieldSetting('datetime_type') == 'datetime') {
-      $element['time_type'] = array(
+      $element['time_type'] = [
         '#type' => 'select',
         '#title' => t('Time type'),
         '#default_value' => $this->getSetting('time_type'),
-        '#options' => array('24' => t('24 hour time'), '12' => t('12 hour time')),
-      );
+        '#options' => ['24' => t('24 hour time'), '12' => t('12 hour time')],
+      ];
 
       $element['increment'] = [
         '#type' => 'select',
@@ -117,10 +120,10 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
       ];
     }
     else {
-      $element['time_type'] = array(
+      $element['time_type'] = [
         '#type' => 'hidden',
         '#value' => 'none',
-      );
+      ];
 
       $element['increment'] = [
         '#type' => 'hidden',
@@ -135,12 +138,12 @@ class DateTimeDatelistWidget extends DateTimeWidgetBase {
    * {@inheritdoc}
    */
   public function settingsSummary() {
-    $summary = array();
+    $summary = [];
 
-    $summary[] = t('Date part order: @order', array('@order' => $this->getSetting('date_order')));
+    $summary[] = t('Date part order: @order', ['@order' => $this->getSetting('date_order')]);
     if ($this->getFieldSetting('datetime_type') == 'datetime') {
-      $summary[] = t('Time type: @time_type', array('@time_type' => $this->getSetting('time_type')));
-      $summary[] = t('Time increments: @increment', array('@increment' => $this->getSetting('increment')));
+      $summary[] = t('Time type: @time_type', ['@time_type' => $this->getSetting('time_type')]);
+      $summary[] = t('Time increments: @increment', ['@increment' => $this->getSetting('increment')]);
     }
 
     return $summary;

core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeDefaultWidget.php

@@ -59,6 +59,16 @@ class DateTimeDefaultWidget extends DateTimeWidgetBase implements ContainerFacto
   public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
     $element = parent::formElement($items, $delta, $element, $form, $form_state);
 
+    // If the field is date-only, make sure the title is displayed. Otherwise,
+    // wrap everything in a fieldset, and the title will be shown in the legend.
+    if ($this->getFieldSetting('datetime_type') === DateTimeItem::DATETIME_TYPE_DATE) {
+      $element['value']['#title'] = $this->fieldDefinition->getLabel();
+      $element['value']['#description'] = $this->fieldDefinition->getDescription();
+    }
+    else {
+      $element['#theme_wrappers'][] = 'fieldset';
+    }
+
     // Identify the type of date and time elements to use.
     switch ($this->getFieldSetting('datetime_type')) {
       case DateTimeItem::DATETIME_TYPE_DATE:
@@ -76,14 +86,14 @@ class DateTimeDefaultWidget extends DateTimeWidgetBase implements ContainerFacto
         break;
     }
 
-    $element['value'] += array(
+    $element['value'] += [
       '#date_date_format' => $date_format,
       '#date_date_element' => $date_type,
-      '#date_date_callbacks' => array(),
+      '#date_date_callbacks' => [],
       '#date_time_format' => $time_format,
       '#date_time_element' => $time_type,
-      '#date_time_callbacks' => array(),
-    );
+      '#date_time_callbacks' => [],
+    ];
 
     return $element;
   }

core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeWidgetBase.php

@@ -17,22 +17,19 @@ class DateTimeWidgetBase extends WidgetBase {
    * {@inheritdoc}
    */
   public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
-    // We are nesting some sub-elements inside the parent, so we need a wrapper.
-    // We also need to add another #title attribute at the top level for ease in
-    // identifying this item in error messages. We do not want to display this
-    // title because the actual title display is handled at a higher level by
-    // the Field module.
-
-    $element['#theme_wrappers'][] = 'datetime_wrapper';
-    $element['#attributes']['class'][] = 'container-inline';
-
-    $element['value'] = array(
+    $element['value'] = [
       '#type' => 'datetime',
       '#default_value' => NULL,
       '#date_increment' => 1,
       '#date_timezone' => drupal_get_user_timezone(),
       '#required' => $element['#required'],
-    );
+    ];
+
+    if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
+      // A date-only field should have no timezone conversion performed, so
+      // use the same timezone as for storage.
+      $element['value']['#date_timezone'] = DATETIME_STORAGE_TIMEZONE;
+    }
 
     if ($items[$delta]->date) {
       $date = $items[$delta]->date;

core/modules/datetime/src/Plugin/migrate/field/d6/DateField.php

@@ -0,0 +1,79 @@
+<?php
+
+namespace Drupal\datetime\Plugin\migrate\field\d6;
+
+use Drupal\migrate\Plugin\MigrationInterface;
+use Drupal\migrate\MigrateException;
+use Drupal\migrate_drupal\Plugin\migrate\field\FieldPluginBase;
+
+/**
+ * @MigrateField(
+ *   id = "date",
+ *   type_map = {
+ *     "date" = "datetime",
+ *     "datestamp" =  "timestamp",
+ *     "datetime" =  "datetime",
+ *   },
+ *   core = {6}
+ * )
+ */
+class DateField extends FieldPluginBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFieldWidgetMap() {
+    return [
+      'date' => 'datetime_default',
+      'datetime' => 'datetime_default',
+      'datestamp' => 'datetime_timestamp',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFieldFormatterMap() {
+    // See d6_field_formatter_settings.yml and
+    // FieldPluginBase::processFieldFormatter().
+    return [];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processFieldValues(MigrationInterface $migration, $field_name, $data) {
+    switch ($data['type']) {
+      case 'date':
+        $from_format = 'Y-m-d\TH:i:s';
+        $to_format = 'Y-m-d\TH:i:s';
+        break;
+      case 'datestamp':
+        $from_format = 'U';
+        $to_format = 'U';
+        break;
+      case 'datetime':
+        $from_format = 'Y-m-d H:i:s';
+        $to_format = 'Y-m-d\TH:i:s';
+        break;
+      default:
+        throw new MigrateException(sprintf('Field %s of type %s is an unknown date field type.', $field_name, var_export($data['type'], TRUE)));
+    }
+    $process = [
+      'value' => [
+        'plugin' => 'format_date',
+        'from_format' => $from_format,
+        'to_format' => $to_format,
+        'source' => 'value',
+      ],
+    ];
+
+    $process = [
+      'plugin' => 'iterator',
+      'source' => $field_name,
+      'process' => $process,
+    ];
+    $migration->mergeProcessOfProperty($field_name, $process);
+  }
+
+}

core/modules/datetime/src/Plugin/views/filter/Date.php

@@ -58,7 +58,7 @@ class Date extends NumericDate implements ContainerFactoryPluginInterface {
    *   The plugin implementation definition.
    * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
    *   The date formatter service.
-   * @param \Symfony\Component\HttpFoundation\RequestStack
+   * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
    *   The request stack used to determine the current time.
    */
   public function __construct(array $configuration, $plugin_id, $plugin_definition, DateFormatterInterface $date_formatter, RequestStack $request_stack) {

core/modules/datetime/src/Tests/DateTestBase.php

@@ -0,0 +1,188 @@
+<?php
+
+namespace Drupal\datetime\Tests;
+
+@trigger_error('\Drupal\datetime\Tests\DateTestBase is deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0. Use \Drupal\Tests\BrowserTestBase instead. See https://www.drupal.org/node/2780063.', E_USER_DEPRECATED);
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Entity\Entity\EntityFormDisplay;
+use Drupal\Core\Entity\Entity\EntityViewDisplay;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Provides a base class for testing Datetime field functionality.
+ *
+ * @deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0.
+ *   Use \Drupal\Tests\BrowserTestBase instead.
+ */
+abstract class DateTestBase extends WebTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = ['node', 'entity_test', 'datetime', 'field_ui'];
+
+  /**
+   * An array of display options to pass to entity_get_display()
+   *
+   * @var array
+   */
+  protected $displayOptions;
+
+  /**
+   * A field storage to use in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldStorageConfig
+   */
+  protected $fieldStorage;
+
+  /**
+   * The field used in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldConfig
+   */
+  protected $field;
+
+  /**
+   * The date formatter service.
+   *
+   * @var \Drupal\Core\Datetime\DateFormatterInterface
+   */
+  protected $dateFormatter;
+
+  /**
+   * An array of timezone extremes to test.
+   *
+   * @var string[]
+   */
+  protected static $timezones = [
+    // UTC-12, no DST.
+    'Pacific/Kwajalein',
+    // UTC-11, no DST
+    'Pacific/Midway',
+    // UTC-7, no DST.
+    'America/Phoenix',
+    // UTC.
+    'UTC',
+    // UTC+5:30, no DST.
+    'Asia/Kolkata',
+    // UTC+12, no DST
+    'Pacific/Funafuti',
+    // UTC+13, no DST.
+    'Pacific/Tongatapu',
+  ];
+
+  /**
+   * Returns the type of field to be tested.
+   *
+   * @return string
+   */
+  abstract protected function getTestFieldType();
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $web_user = $this->drupalCreateUser([
+      'access content',
+      'view test entity',
+      'administer entity_test content',
+      'administer entity_test form display',
+      'administer content types',
+      'administer node fields',
+    ]);
+    $this->drupalLogin($web_user);
+
+    // Create a field with settings to validate.
+    $this->createField();
+
+    $this->dateFormatter = $this->container->get('date.formatter');
+  }
+
+  /**
+   * Creates a date test field.
+   */
+  protected function createField() {
+    $field_name = Unicode::strtolower($this->randomMachineName());
+    $type = $this->getTestFieldType();
+    $widget_type = $formatter_type = $type . '_default';
+
+    $this->fieldStorage = FieldStorageConfig::create([
+      'field_name' => $field_name,
+      'entity_type' => 'entity_test',
+      'type' => $type,
+      'settings' => ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATE],
+    ]);
+    $this->fieldStorage->save();
+    $this->field = FieldConfig::create([
+      'field_storage' => $this->fieldStorage,
+      'bundle' => 'entity_test',
+      'description' => 'Description for ' . $field_name,
+      'required' => TRUE,
+    ]);
+    $this->field->save();
+
+    EntityFormDisplay::load('entity_test.entity_test.default')
+      ->setComponent($field_name, ['type' => $widget_type])
+      ->save();
+
+    $this->displayOptions = [
+      'type' => $formatter_type,
+      'label' => 'hidden',
+      'settings' => ['format_type' => 'medium'] + $this->defaultSettings,
+    ];
+    EntityViewDisplay::create([
+      'targetEntityType' => $this->field->getTargetEntityTypeId(),
+      'bundle' => $this->field->getTargetBundle(),
+      'mode' => 'full',
+      'status' => TRUE,
+    ])->setComponent($field_name, $this->displayOptions)
+      ->save();
+  }
+
+  /**
+   * Renders a entity_test and sets the output in the internal browser.
+   *
+   * @param int $id
+   *   The entity_test ID to render.
+   * @param string $view_mode
+   *   (optional) The view mode to use for rendering. Defaults to 'full'.
+   * @param bool $reset
+   *   (optional) Whether to reset the entity_test controller cache. Defaults to
+   *   TRUE to simplify testing.
+   */
+  protected function renderTestEntity($id, $view_mode = 'full', $reset = TRUE) {
+    if ($reset) {
+      $this->container->get('entity_type.manager')->getStorage('entity_test')->resetCache([$id]);
+    }
+    $entity = EntityTest::load($id);
+    $display = EntityViewDisplay::collectRenderDisplay($entity, $view_mode);
+    $build = $display->build($entity);
+    $output = $this->container->get('renderer')->renderRoot($build);
+    $this->setRawContent($output);
+    $this->verbose($output);
+  }
+
+  /**
+   * Sets the site timezone to a given timezone.
+   *
+   * @param string $timezone
+   *   The timezone identifier to set.
+   */
+  protected function setSiteTimezone($timezone) {
+    // Set an explicit site timezone, and disallow per-user timezones.
+    $this->config('system.date')
+      ->set('timezone.user.configurable', 0)
+      ->set('timezone.default', $timezone)
+      ->save();
+  }
+
+}

core/modules/datetime/src/Tests/Views/FilterDateTimeTest.php

@@ -136,7 +136,8 @@ class FilterDateTimeTest extends DateTimeHandlerTestBase {
     $view->initHandlers();
     $view->filter[$field]->operator = 'not between';
     $view->filter[$field]->value['min'] = '2001-01-01';
-    $view->filter[$field]->value['max'] = '2002-01-01';
+    // Set maximum date to date of node 1 to test range borders.
+    $view->filter[$field]->value['max'] = '2001-10-10T12:12:12';
     $view->setDisplay('default');
     $this->executeView($view);
     $expected_result = [

core/modules/datetime/tests/modules/datetime_test/datetime_test.info.yml

@@ -7,8 +7,8 @@ package: Testing
 dependencies:
   - views
 
-# Information added by Drupal.org packaging script on 2016-08-03
-version: '8.1.8'
+# Information added by Drupal.org packaging script on 2017-08-16
+version: '8.3.7'
 core: '8.x'
 project: 'drupal'
-datestamp: 1470233790
+datestamp: 1502903957

core/modules/datetime/tests/src/Functional/DateTestBase.php

@@ -0,0 +1,184 @@
+<?php
+
+namespace Drupal\Tests\datetime\Functional;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Entity\Entity\EntityFormDisplay;
+use Drupal\Core\Entity\Entity\EntityViewDisplay;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\BrowserTestBase;
+
+/**
+ * Provides a base class for testing Datetime field functionality.
+ */
+abstract class DateTestBase extends BrowserTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = ['node', 'entity_test', 'datetime', 'field_ui'];
+
+  /**
+   * An array of display options to pass to entity_get_display()
+   *
+   * @var array
+   */
+  protected $displayOptions;
+
+  /**
+   * A field storage to use in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldStorageConfig
+   */
+  protected $fieldStorage;
+
+  /**
+   * The field used in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldConfig
+   */
+  protected $field;
+
+  /**
+   * The date formatter service.
+   *
+   * @var \Drupal\Core\Datetime\DateFormatterInterface
+   */
+  protected $dateFormatter;
+
+  /**
+   * An array of timezone extremes to test.
+   *
+   * @var string[]
+   */
+  protected static $timezones = [
+    // UTC-12, no DST.
+    'Pacific/Kwajalein',
+    // UTC-11, no DST
+    'Pacific/Midway',
+    // UTC-7, no DST.
+    'America/Phoenix',
+    // UTC.
+    'UTC',
+    // UTC+5:30, no DST.
+    'Asia/Kolkata',
+    // UTC+12, no DST
+    'Pacific/Funafuti',
+    // UTC+13, no DST.
+    'Pacific/Tongatapu',
+  ];
+
+  /**
+   * Returns the type of field to be tested.
+   *
+   * @return string
+   */
+  abstract protected function getTestFieldType();
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $web_user = $this->drupalCreateUser([
+      'access content',
+      'view test entity',
+      'administer entity_test content',
+      'administer entity_test form display',
+      'administer content types',
+      'administer node fields',
+    ]);
+    $this->drupalLogin($web_user);
+
+    // Create a field with settings to validate.
+    $this->createField();
+
+    $this->dateFormatter = $this->container->get('date.formatter');
+  }
+
+  /**
+   * Creates a date test field.
+   */
+  protected function createField() {
+    $field_name = Unicode::strtolower($this->randomMachineName());
+    $type = $this->getTestFieldType();
+    $widget_type = $formatter_type = $type . '_default';
+
+    $this->fieldStorage = FieldStorageConfig::create([
+      'field_name' => $field_name,
+      'entity_type' => 'entity_test',
+      'type' => $type,
+      'settings' => ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATE],
+    ]);
+    $this->fieldStorage->save();
+    $this->field = FieldConfig::create([
+      'field_storage' => $this->fieldStorage,
+      'bundle' => 'entity_test',
+      'description' => 'Description for ' . $field_name,
+      'required' => TRUE,
+    ]);
+    $this->field->save();
+
+    EntityFormDisplay::load('entity_test.entity_test.default')
+      ->setComponent($field_name, ['type' => $widget_type])
+      ->save();
+
+    $this->displayOptions = [
+      'type' => $formatter_type,
+      'label' => 'hidden',
+      'settings' => ['format_type' => 'medium'] + $this->defaultSettings,
+    ];
+    EntityViewDisplay::create([
+      'targetEntityType' => $this->field->getTargetEntityTypeId(),
+      'bundle' => $this->field->getTargetBundle(),
+      'mode' => 'full',
+      'status' => TRUE,
+    ])->setComponent($field_name, $this->displayOptions)
+      ->save();
+  }
+
+  /**
+   * Renders a entity_test and sets the output in the internal browser.
+   *
+   * @param int $id
+   *   The entity_test ID to render.
+   * @param string $view_mode
+   *   (optional) The view mode to use for rendering. Defaults to 'full'.
+   * @param bool $reset
+   *   (optional) Whether to reset the entity_test controller cache. Defaults to
+   *   TRUE to simplify testing.
+   *
+   * @return string
+   *   The rendered HTML output.
+   */
+  protected function renderTestEntity($id, $view_mode = 'full', $reset = TRUE) {
+    if ($reset) {
+      $this->container->get('entity_type.manager')->getStorage('entity_test')->resetCache([$id]);
+    }
+    $entity = EntityTest::load($id);
+    $display = EntityViewDisplay::collectRenderDisplay($entity, $view_mode);
+    $build = $display->build($entity);
+    return (string) $this->container->get('renderer')->renderRoot($build);
+  }
+
+  /**
+   * Sets the site timezone to a given timezone.
+   *
+   * @param string $timezone
+   *   The timezone identifier to set.
+   */
+  protected function setSiteTimezone($timezone) {
+    // Set an explicit site timezone, and disallow per-user timezones.
+    $this->config('system.date')
+      ->set('timezone.user.configurable', 0)
+      ->set('timezone.default', $timezone)
+      ->save();
+  }
+
+}

core/modules/datetime/tests/src/Functional/DateTimeFieldTest.php

@@ -0,0 +1,843 @@
+<?php
+
+namespace Drupal\Tests\datetime\Functional;
+
+use Drupal\Component\Render\FormattableMarkup;
+use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\Core\Datetime\Entity\DateFormat;
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\node\Entity\Node;
+
+/**
+ * Tests Datetime field functionality.
+ *
+ * @group datetime
+ */
+class DateTimeFieldTest extends DateTestBase {
+
+  /**
+   * The default display settings to use for the formatters.
+   *
+   * @var array
+   */
+  protected $defaultSettings = ['timezone_override' => ''];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getTestFieldType() {
+    return 'datetime';
+  }
+
+  /**
+   * Tests date field functionality.
+   */
+  public function testDateField() {
+    $field_name = $this->fieldStorage->getName();
+
+    // Loop through defined timezones to test that date-only fields work at the
+    // extremes.
+    foreach (static::$timezones as $timezone) {
+
+      $this->setSiteTimezone($timezone);
+
+      // Display creation form.
+      $this->drupalGet('entity_test/add');
+      $this->assertFieldByName("{$field_name}[0][value][date]", '', 'Date element found.');
+      $this->assertFieldByXPath('//*[@id="edit-' . $field_name . '-wrapper"]//label[contains(@class,"js-form-required")]', TRUE, 'Required markup found');
+      $this->assertNoFieldByName("{$field_name}[0][value][time]", '', 'Time element not found.');
+      $this->assertFieldByXPath('//input[@aria-describedby="edit-' . $field_name . '-0-value--description"]', NULL, 'ARIA described-by found');
+      $this->assertFieldByXPath('//div[@id="edit-' . $field_name . '-0-value--description"]', NULL, 'ARIA description found');
+
+      // Build up a date in the UTC timezone. Note that using this will also
+      // mimic the user in a different timezone simply entering '2012-12-31' via
+      // the UI.
+      $value = '2012-12-31 00:00:00';
+      $date = new DrupalDateTime($value, DATETIME_STORAGE_TIMEZONE);
+
+      // Submit a valid date and ensure it is accepted.
+      $date_format = DateFormat::load('html_date')->getPattern();
+      $time_format = DateFormat::load('html_time')->getPattern();
+
+      $edit = [
+        "{$field_name}[0][value][date]" => $date->format($date_format),
+      ];
+      $this->drupalPostForm(NULL, $edit, t('Save'));
+      preg_match('|entity_test/manage/(\d+)|', $this->getUrl(), $match);
+      $id = $match[1];
+      $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
+      $this->assertRaw($date->format($date_format));
+      $this->assertNoRaw($date->format($time_format));
+
+      // Verify the date doesn't change if using a timezone that is UTC+12 when
+      // the entity is edited through the form.
+      $entity = EntityTest::load($id);
+      $this->assertEqual('2012-12-31', $entity->{$field_name}->value);
+      $this->drupalGet('entity_test/manage/' . $id . '/edit');
+      $this->drupalPostForm(NULL, [], t('Save'));
+      $this->drupalGet('entity_test/manage/' . $id . '/edit');
+      $this->drupalPostForm(NULL, [], t('Save'));
+      $this->drupalGet('entity_test/manage/' . $id . '/edit');
+      $this->drupalPostForm(NULL, [], t('Save'));
+      $entity = EntityTest::load($id);
+      $this->assertEqual('2012-12-31', $entity->{$field_name}->value);
+
+      // Reset display options since these get changed below.
+      $this->displayOptions = [
+        'type' => 'datetime_default',
+        'label' => 'hidden',
+        'settings' => ['format_type' => 'medium'] + $this->defaultSettings,
+      ];
+      // Verify that the date is output according to the formatter settings.
+      $options = [
+        'format_type' => ['short', 'medium', 'long'],
+      ];
+      // Formats that display a time component for date-only fields will display
+      // the default time, so that is applied before calculating the expected
+      // value.
+      datetime_date_default_time($date);
+      foreach ($options as $setting => $values) {
+        foreach ($values as $new_value) {
+          // Update the entity display settings.
+          $this->displayOptions['settings'] = [$setting => $new_value] + $this->defaultSettings;
+          entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+            ->setComponent($field_name, $this->displayOptions)
+            ->save();
+
+          $this->renderTestEntity($id);
+          switch ($setting) {
+            case 'format_type':
+              // Verify that a date is displayed. Since this is a date-only
+              // field, it is expected to display the time as 00:00:00.
+              $expected = format_date($date->getTimestamp(), $new_value, '', DATETIME_STORAGE_TIMEZONE);
+              $expected_iso = format_date($date->getTimestamp(), 'custom', 'Y-m-d\TH:i:s\Z', DATETIME_STORAGE_TIMEZONE);
+              $output = $this->renderTestEntity($id);
+              $expected_markup = '<time datetime="' . $expected_iso . '" class="datetime">' . $expected . '</time>';
+              $this->assertContains($expected_markup, $output, SafeMarkup::format('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => $new_value, '%expected' => $expected, '%expected_iso' => $expected_iso]));
+              break;
+          }
+        }
+      }
+
+      // Verify that the plain formatter works.
+      $this->displayOptions['type'] = 'datetime_plain';
+      $this->displayOptions['settings'] = $this->defaultSettings;
+      entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+        ->setComponent($field_name, $this->displayOptions)
+        ->save();
+      $expected = $date->format(DATETIME_DATE_STORAGE_FORMAT);
+      $output = $this->renderTestEntity($id);
+      $this->assertContains($expected, $output, SafeMarkup::format('Formatted date field using plain format displayed as %expected.', ['%expected' => $expected]));
+
+      // Verify that the 'datetime_custom' formatter works.
+      $this->displayOptions['type'] = 'datetime_custom';
+      $this->displayOptions['settings'] = ['date_format' => 'm/d/Y'] + $this->defaultSettings;
+      entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+        ->setComponent($field_name, $this->displayOptions)
+        ->save();
+      $expected = $date->format($this->displayOptions['settings']['date_format']);
+      $output = $this->renderTestEntity($id);
+      $this->assertContains($expected, $output, SafeMarkup::format('Formatted date field using datetime_custom format displayed as %expected.', ['%expected' => $expected]));
+
+      // Test that allowed markup in custom format is preserved and XSS is
+      // removed.
+      $this->displayOptions['settings']['date_format'] = '\\<\\s\\t\\r\\o\\n\\g\\>m/d/Y\\<\\/\\s\\t\\r\\o\\n\\g\\>\\<\\s\\c\\r\\i\\p\\t\\>\\a\\l\\e\\r\\t\\(\\S\\t\\r\\i\\n\\g\\.\\f\\r\\o\\m\\C\\h\\a\\r\\C\\o\\d\\e\\(\\8\\8\\,\\8\\3\\,\\8\\3\\)\\)\\<\\/\\s\\c\\r\\i\\p\\t\\>';
+      entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+        ->setComponent($field_name, $this->displayOptions)
+        ->save();
+      $expected = '<strong>' . $date->format('m/d/Y') . '</strong>alert(String.fromCharCode(88,83,83))';
+      $output = $this->renderTestEntity($id);
+      $this->assertContains($expected, $output, new FormattableMarkup('Formatted date field using daterange_custom format displayed as %expected.', ['%expected' => $expected]));
+
+      // Verify that the 'datetime_time_ago' formatter works for intervals in the
+      // past.  First update the test entity so that the date difference always
+      // has the same interval.  Since the database always stores UTC, and the
+      // interval will use this, force the test date to use UTC and not the local
+      // or user timezome.
+      $timestamp = REQUEST_TIME - 87654321;
+      $entity = EntityTest::load($id);
+      $field_name = $this->fieldStorage->getName();
+      $date = DrupalDateTime::createFromTimestamp($timestamp, 'UTC');
+      $entity->{$field_name}->value = $date->format($date_format);
+      $entity->save();
+
+      $this->displayOptions['type'] = 'datetime_time_ago';
+      $this->displayOptions['settings'] = [
+        'future_format' => '@interval in the future',
+        'past_format' => '@interval in the past',
+        'granularity' => 3,
+      ];
+      entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+        ->setComponent($field_name, $this->displayOptions)
+        ->save();
+      $expected = SafeMarkup::format($this->displayOptions['settings']['past_format'], [
+        '@interval' => $this->dateFormatter->formatTimeDiffSince($timestamp, ['granularity' => $this->displayOptions['settings']['granularity']])
+      ]);
+      $output = $this->renderTestEntity($id);
+      $this->assertContains((string) $expected, $output, SafeMarkup::format('Formatted date field using datetime_time_ago format displayed as %expected.', ['%expected' => $expected]));
+
+      // Verify that the 'datetime_time_ago' formatter works for intervals in the
+      // future.  First update the test entity so that the date difference always
+      // has the same interval.  Since the database always stores UTC, and the
+      // interval will use this, force the test date to use UTC and not the local
+      // or user timezome.
+      $timestamp = REQUEST_TIME + 87654321;
+      $entity = EntityTest::load($id);
+      $field_name = $this->fieldStorage->getName();
+      $date = DrupalDateTime::createFromTimestamp($timestamp, 'UTC');
+      $entity->{$field_name}->value = $date->format($date_format);
+      $entity->save();
+
+      entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+        ->setComponent($field_name, $this->displayOptions)
+        ->save();
+      $expected = SafeMarkup::format($this->displayOptions['settings']['future_format'], [
+        '@interval' => $this->dateFormatter->formatTimeDiffUntil($timestamp, ['granularity' => $this->displayOptions['settings']['granularity']])
+      ]);
+      $output = $this->renderTestEntity($id);
+      $this->assertContains((string) $expected, $output, SafeMarkup::format('Formatted date field using datetime_time_ago format displayed as %expected.', ['%expected' => $expected]));
+    }
+  }
+
+  /**
+   * Tests date and time field.
+   */
+  public function testDatetimeField() {
+    $field_name = $this->fieldStorage->getName();
+    // Change the field to a datetime field.
+    $this->fieldStorage->setSetting('datetime_type', 'datetime');
+    $this->fieldStorage->save();
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+    $this->assertFieldByName("{$field_name}[0][value][date]", '', 'Date element found.');
+    $this->assertFieldByName("{$field_name}[0][value][time]", '', 'Time element found.');
+    $this->assertFieldByXPath('//fieldset[@id="edit-' . $field_name . '-0"]/legend', $field_name, 'Fieldset and label found');
+    $this->assertFieldByXPath('//fieldset[@aria-describedby="edit-' . $field_name . '-0--description"]', NULL, 'ARIA described-by found');
+    $this->assertFieldByXPath('//div[@id="edit-' . $field_name . '-0--description"]', NULL, 'ARIA description found');
+
+    // Build up a date in the UTC timezone.
+    $value = '2012-12-31 00:00:00';
+    $date = new DrupalDateTime($value, 'UTC');
+
+    // Update the timezone to the system default.
+    $date->setTimezone(timezone_open(drupal_get_user_timezone()));
+
+    // Submit a valid date and ensure it is accepted.
+    $date_format = DateFormat::load('html_date')->getPattern();
+    $time_format = DateFormat::load('html_time')->getPattern();
+
+    $edit = [
+      "{$field_name}[0][value][date]" => $date->format($date_format),
+      "{$field_name}[0][value][time]" => $date->format($time_format),
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    preg_match('|entity_test/manage/(\d+)|', $this->getUrl(), $match);
+    $id = $match[1];
+    $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
+    $this->assertRaw($date->format($date_format));
+    $this->assertRaw($date->format($time_format));
+
+    // Verify that the date is output according to the formatter settings.
+    $options = [
+      'format_type' => ['short', 'medium', 'long'],
+    ];
+    foreach ($options as $setting => $values) {
+      foreach ($values as $new_value) {
+        // Update the entity display settings.
+        $this->displayOptions['settings'] = [$setting => $new_value] + $this->defaultSettings;
+        entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+          ->setComponent($field_name, $this->displayOptions)
+          ->save();
+
+        $this->renderTestEntity($id);
+        switch ($setting) {
+          case 'format_type':
+            // Verify that a date is displayed.
+            $expected = format_date($date->getTimestamp(), $new_value);
+            $expected_iso = format_date($date->getTimestamp(), 'custom', 'Y-m-d\TH:i:s\Z', 'UTC');
+            $output = $this->renderTestEntity($id);
+            $expected_markup = '<time datetime="' . $expected_iso . '" class="datetime">' . $expected . '</time>';
+            $this->assertContains($expected_markup, $output, SafeMarkup::format('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => $new_value, '%expected' => $expected, '%expected_iso' => $expected_iso]));
+            break;
+        }
+      }
+    }
+
+    // Verify that the plain formatter works.
+    $this->displayOptions['type'] = 'datetime_plain';
+    $this->displayOptions['settings'] = $this->defaultSettings;
+    entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+      ->setComponent($field_name, $this->displayOptions)
+      ->save();
+    $expected = $date->format(DATETIME_DATETIME_STORAGE_FORMAT);
+    $output = $this->renderTestEntity($id);
+    $this->assertContains($expected, $output, SafeMarkup::format('Formatted date field using plain format displayed as %expected.', ['%expected' => $expected]));
+
+    // Verify that the 'datetime_custom' formatter works.
+    $this->displayOptions['type'] = 'datetime_custom';
+    $this->displayOptions['settings'] = ['date_format' => 'm/d/Y g:i:s A'] + $this->defaultSettings;
+    entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+      ->setComponent($field_name, $this->displayOptions)
+      ->save();
+    $expected = $date->format($this->displayOptions['settings']['date_format']);
+    $output = $this->renderTestEntity($id);
+    $this->assertContains($expected, $output, SafeMarkup::format('Formatted date field using datetime_custom format displayed as %expected.', ['%expected' => $expected]));
+
+    // Verify that the 'timezone_override' setting works.
+    $this->displayOptions['type'] = 'datetime_custom';
+    $this->displayOptions['settings'] = ['date_format' => 'm/d/Y g:i:s A', 'timezone_override' => 'America/New_York'] + $this->defaultSettings;
+    entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+      ->setComponent($field_name, $this->displayOptions)
+      ->save();
+    $expected = $date->format($this->displayOptions['settings']['date_format'], ['timezone' => 'America/New_York']);
+    $output = $this->renderTestEntity($id);
+    $this->assertContains($expected, $output, SafeMarkup::format('Formatted date field using datetime_custom format displayed as %expected.', ['%expected' => $expected]));
+
+    // Verify that the 'datetime_time_ago' formatter works for intervals in the
+    // past.  First update the test entity so that the date difference always
+    // has the same interval.  Since the database always stores UTC, and the
+    // interval will use this, force the test date to use UTC and not the local
+    // or user timezome.
+    $timestamp = REQUEST_TIME - 87654321;
+    $entity = EntityTest::load($id);
+    $field_name = $this->fieldStorage->getName();
+    $date = DrupalDateTime::createFromTimestamp($timestamp, 'UTC');
+    $entity->{$field_name}->value = $date->format(DATETIME_DATETIME_STORAGE_FORMAT);
+    $entity->save();
+
+    $this->displayOptions['type'] = 'datetime_time_ago';
+    $this->displayOptions['settings'] = [
+      'future_format' => '@interval from now',
+      'past_format' => '@interval earlier',
+      'granularity' => 3,
+    ];
+    entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+      ->setComponent($field_name, $this->displayOptions)
+      ->save();
+    $expected = SafeMarkup::format($this->displayOptions['settings']['past_format'], [
+      '@interval' => $this->dateFormatter->formatTimeDiffSince($timestamp, ['granularity' => $this->displayOptions['settings']['granularity']])
+    ]);
+    $output = $this->renderTestEntity($id);
+    $this->assertContains((string) $expected, $output, SafeMarkup::format('Formatted date field using datetime_time_ago format displayed as %expected.', ['%expected' => $expected]));
+
+    // Verify that the 'datetime_time_ago' formatter works for intervals in the
+    // future.  First update the test entity so that the date difference always
+    // has the same interval.  Since the database always stores UTC, and the
+    // interval will use this, force the test date to use UTC and not the local
+    // or user timezome.
+    $timestamp = REQUEST_TIME + 87654321;
+    $entity = EntityTest::load($id);
+    $field_name = $this->fieldStorage->getName();
+    $date = DrupalDateTime::createFromTimestamp($timestamp, 'UTC');
+    $entity->{$field_name}->value = $date->format(DATETIME_DATETIME_STORAGE_FORMAT);
+    $entity->save();
+
+    entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
+      ->setComponent($field_name, $this->displayOptions)
+      ->save();
+    $expected = SafeMarkup::format($this->displayOptions['settings']['future_format'], [
+      '@interval' => $this->dateFormatter->formatTimeDiffUntil($timestamp, ['granularity' => $this->displayOptions['settings']['granularity']])
+    ]);
+    $output = $this->renderTestEntity($id);
+    $this->assertContains((string) $expected, $output, SafeMarkup::format('Formatted date field using datetime_time_ago format displayed as %expected.', ['%expected' => $expected]));
+  }
+
+  /**
+   * Tests Date List Widget functionality.
+   */
+  public function testDatelistWidget() {
+    $field_name = $this->fieldStorage->getName();
+
+    // Ensure field is set to a date only field.
+    $this->fieldStorage->setSetting('datetime_type', 'date');
+    $this->fieldStorage->save();
+
+    // Change the widget to a datelist widget.
+    entity_get_form_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'default')
+      ->setComponent($field_name, [
+        'type' => 'datetime_datelist',
+        'settings' => [
+          'date_order' => 'YMD',
+        ],
+      ])
+      ->save();
+    \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+    $this->assertFieldByXPath('//fieldset[@id="edit-' . $field_name . '-0"]/legend', $field_name, 'Fieldset and label found');
+    $this->assertFieldByXPath('//fieldset[@aria-describedby="edit-' . $field_name . '-0--description"]', NULL, 'ARIA described-by found');
+    $this->assertFieldByXPath('//div[@id="edit-' . $field_name . '-0--description"]', NULL, 'ARIA description found');
+
+    // Assert that Hour and Minute Elements do not appear on Date Only
+    $this->assertNoFieldByXPath("//*[@id=\"edit-$field_name-0-value-hour\"]", NULL, 'Hour element not found on Date Only.');
+    $this->assertNoFieldByXPath("//*[@id=\"edit-$field_name-0-value-minute\"]", NULL, 'Minute element not found on Date Only.');
+
+    // Go to the form display page to assert that increment option does not appear on Date Only
+    $fieldEditUrl = 'entity_test/structure/entity_test/form-display';
+    $this->drupalGet($fieldEditUrl);
+
+    // Click on the widget settings button to open the widget settings form.
+    $this->drupalPostForm(NULL, [], $field_name . "_settings_edit");
+    $xpathIncr = "//select[starts-with(@id, \"edit-fields-$field_name-settings-edit-form-settings-increment\")]";
+    $this->assertNoFieldByXPath($xpathIncr, NULL, 'Increment element not found for Date Only.');
+
+    // Change the field to a datetime field.
+    $this->fieldStorage->setSetting('datetime_type', 'datetime');
+    $this->fieldStorage->save();
+
+    // Change the widget to a datelist widget.
+    entity_get_form_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'default')
+      ->setComponent($field_name, [
+        'type' => 'datetime_datelist',
+        'settings' => [
+          'increment' => 1,
+          'date_order' => 'YMD',
+          'time_type' => '12',
+        ],
+      ])
+      ->save();
+    \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+    // Go to the form display page to assert that increment option does appear on Date Time
+    $fieldEditUrl = 'entity_test/structure/entity_test/form-display';
+    $this->drupalGet($fieldEditUrl);
+
+    // Click on the widget settings button to open the widget settings form.
+    $this->drupalPostForm(NULL, [], $field_name . "_settings_edit");
+    $this->assertFieldByXPath($xpathIncr, NULL, 'Increment element found for Date and time.');
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-year\"]", NULL, 'Year element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-year", '', 'No year selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-year", t('Year'));
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-month\"]", NULL, 'Month element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-month", '', 'No month selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-month", t('Month'));
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-day\"]", NULL, 'Day element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-day", '', 'No day selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-day", t('Day'));
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-hour\"]", NULL, 'Hour element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-hour", '', 'No hour selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-hour", t('Hour'));
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-minute\"]", NULL, 'Minute element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-minute", '', 'No minute selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-minute", t('Minute'));
+    $this->assertNoFieldByXPath("//*[@id=\"edit-$field_name-0-value-second\"]", NULL, 'Second element not found.');
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-ampm\"]", NULL, 'AMPM element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-ampm", '', 'No ampm selected.');
+    $this->assertOptionByText("edit-$field_name-0-value-ampm", t('AM/PM'));
+
+    // Submit a valid date and ensure it is accepted.
+    $date_value = ['year' => 2012, 'month' => 12, 'day' => 31, 'hour' => 5, 'minute' => 15];
+
+    $edit = [];
+    // Add the ampm indicator since we are testing 12 hour time.
+    $date_value['ampm'] = 'am';
+    foreach ($date_value as $part => $value) {
+      $edit["{$field_name}[0][value][$part]"] = $value;
+    }
+
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    preg_match('|entity_test/manage/(\d+)|', $this->getUrl(), $match);
+    $id = $match[1];
+    $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
+
+    $this->assertOptionSelected("edit-$field_name-0-value-year", '2012', 'Correct year selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-month", '12', 'Correct month selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-day", '31', 'Correct day selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-hour", '5', 'Correct hour selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-minute", '15', 'Correct minute selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-ampm", 'am', 'Correct ampm selected.');
+
+    // Test the widget using increment other than 1 and 24 hour mode.
+    entity_get_form_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'default')
+      ->setComponent($field_name, [
+        'type' => 'datetime_datelist',
+        'settings' => [
+          'increment' => 15,
+          'date_order' => 'YMD',
+          'time_type' => '24',
+        ],
+      ])
+      ->save();
+    \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+
+    // Other elements are unaffected by the changed settings.
+    $this->assertFieldByXPath("//*[@id=\"edit-$field_name-0-value-hour\"]", NULL, 'Hour element found.');
+    $this->assertOptionSelected("edit-$field_name-0-value-hour", '', 'No hour selected.');
+    $this->assertNoFieldByXPath("//*[@id=\"edit-$field_name-0-value-ampm\"]", NULL, 'AMPM element not found.');
+
+    // Submit a valid date and ensure it is accepted.
+    $date_value = ['year' => 2012, 'month' => 12, 'day' => 31, 'hour' => 17, 'minute' => 15];
+
+    $edit = [];
+    foreach ($date_value as $part => $value) {
+      $edit["{$field_name}[0][value][$part]"] = $value;
+    }
+
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    preg_match('|entity_test/manage/(\d+)|', $this->getUrl(), $match);
+    $id = $match[1];
+    $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
+
+    $this->assertOptionSelected("edit-$field_name-0-value-year", '2012', 'Correct year selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-month", '12', 'Correct month selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-day", '31', 'Correct day selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-hour", '17', 'Correct hour selected.');
+    $this->assertOptionSelected("edit-$field_name-0-value-minute", '15', 'Correct minute selected.');
+
+    // Test the widget for partial completion of fields.
+    entity_get_form_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'default')
+      ->setComponent($field_name, [
+        'type' => 'datetime_datelist',
+        'settings' => [
+          'increment' => 1,
+          'date_order' => 'YMD',
+          'time_type' => '24',
+        ],
+      ])
+      ->save();
+    \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+    // Test the widget for validation notifications.
+    foreach ($this->datelistDataProvider() as $data) {
+      list($date_value, $expected) = $data;
+
+      // Display creation form.
+      $this->drupalGet('entity_test/add');
+
+      // Submit a partial date and ensure and error message is provided.
+      $edit = [];
+      foreach ($date_value as $part => $value) {
+        $edit["{$field_name}[0][value][$part]"] = $value;
+      }
+
+      $this->drupalPostForm(NULL, $edit, t('Save'));
+      $this->assertResponse(200);
+      foreach ($expected as $expected_text) {
+        $this->assertText(t($expected_text));
+      }
+    }
+
+    // Test the widget for complete input with zeros as part of selections.
+    $this->drupalGet('entity_test/add');
+
+    $date_value = ['year' => 2012, 'month' => '12', 'day' => '31', 'hour' => '0', 'minute' => '0'];
+    $edit = [];
+    foreach ($date_value as $part => $value) {
+      $edit["{$field_name}[0][value][$part]"] = $value;
+    }
+
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertResponse(200);
+    preg_match('|entity_test/manage/(\d+)|', $this->getUrl(), $match);
+    $id = $match[1];
+    $this->assertText(t('entity_test @id has been created.', ['@id' => $id]));
+
+    // Test the widget to ensure zeros are not deselected on validation.
+    $this->drupalGet('entity_test/add');
+
+    $date_value = ['year' => 2012, 'month' => '12', 'day' => '31', 'hour' => '', 'minute' => '0'];
+    $edit = [];
+    foreach ($date_value as $part => $value) {
+      $edit["{$field_name}[0][value][$part]"] = $value;
+    }
+
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertResponse(200);
+    $this->assertOptionSelected("edit-$field_name-0-value-minute", '0', 'Correct minute selected.');
+  }
+
+  /**
+   * The data provider for testing the validation of the datelist widget.
+   *
+   * @return array
+   *   An array of datelist input permutations to test.
+   */
+  protected function datelistDataProvider() {
+    return [
+      // Year only selected, validation error on Month, Day, Hour, Minute.
+      [['year' => 2012, 'month' => '', 'day' => '', 'hour' => '', 'minute' => ''], [
+        'A value must be selected for month.',
+        'A value must be selected for day.',
+        'A value must be selected for hour.',
+        'A value must be selected for minute.',
+      ]],
+      // Year and Month selected, validation error on Day, Hour, Minute.
+      [['year' => 2012, 'month' => '12', 'day' => '', 'hour' => '', 'minute' => ''], [
+        'A value must be selected for day.',
+        'A value must be selected for hour.',
+        'A value must be selected for minute.',
+      ]],
+      // Year, Month and Day selected, validation error on Hour, Minute.
+      [['year' => 2012, 'month' => '12', 'day' => '31', 'hour' => '', 'minute' => ''], [
+        'A value must be selected for hour.',
+        'A value must be selected for minute.',
+      ]],
+      // Year, Month, Day and Hour selected, validation error on Minute only.
+      [['year' => 2012, 'month' => '12', 'day' => '31', 'hour' => '0', 'minute' => ''], [
+        'A value must be selected for minute.',
+      ]],
+    ];
+  }
+
+  /**
+   * Test default value functionality.
+   */
+  public function testDefaultValue() {
+    // Create a test content type.
+    $this->drupalCreateContentType(['type' => 'date_content']);
+
+    // Create a field storage with settings to validate.
+    $field_name = Unicode::strtolower($this->randomMachineName());
+    $field_storage = FieldStorageConfig::create([
+      'field_name' => $field_name,
+      'entity_type' => 'node',
+      'type' => 'datetime',
+      'settings' => ['datetime_type' => 'date'],
+    ]);
+    $field_storage->save();
+
+    $field = FieldConfig::create([
+      'field_storage' => $field_storage,
+      'bundle' => 'date_content',
+    ]);
+    $field->save();
+
+    // Loop through defined timezones to test that date-only defaults work at
+    // the extremes.
+    foreach (static::$timezones as $timezone) {
+
+      $this->setSiteTimezone($timezone);
+
+      // Set now as default_value.
+      $field_edit = [
+        'default_value_input[default_date_type]' => 'now',
+      ];
+      $this->drupalPostForm('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name, $field_edit, t('Save settings'));
+
+      // Check that default value is selected in default value form.
+      $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name);
+      $this->assertOptionSelected('edit-default-value-input-default-date-type', 'now', 'The default value is selected in instance settings page');
+      $this->assertFieldByName('default_value_input[default_date]', '', 'The relative default value is empty in instance settings page');
+
+      // Check if default_date has been stored successfully.
+      $config_entity = $this->config('field.field.node.date_content.' . $field_name)
+        ->get();
+      $this->assertEqual($config_entity['default_value'][0], [
+        'default_date_type' => 'now',
+        'default_date' => 'now',
+      ], 'Default value has been stored successfully');
+
+      // Clear field cache in order to avoid stale cache values.
+      \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+      // Create a new node to check that datetime field default value is today.
+      $new_node = Node::create(['type' => 'date_content']);
+      $expected_date = new DrupalDateTime('now', drupal_get_user_timezone());
+      $this->assertEqual($new_node->get($field_name)
+        ->offsetGet(0)->value, $expected_date->format(DATETIME_DATE_STORAGE_FORMAT));
+
+      // Set an invalid relative default_value to test validation.
+      $field_edit = [
+        'default_value_input[default_date_type]' => 'relative',
+        'default_value_input[default_date]' => 'invalid date',
+      ];
+      $this->drupalPostForm('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name, $field_edit, t('Save settings'));
+
+      $this->assertText('The relative date value entered is invalid.');
+
+      // Set a relative default_value.
+      $field_edit = [
+        'default_value_input[default_date_type]' => 'relative',
+        'default_value_input[default_date]' => '+90 days',
+      ];
+      $this->drupalPostForm('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name, $field_edit, t('Save settings'));
+
+      // Check that default value is selected in default value form.
+      $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name);
+      $this->assertOptionSelected('edit-default-value-input-default-date-type', 'relative', 'The default value is selected in instance settings page');
+      $this->assertFieldByName('default_value_input[default_date]', '+90 days', 'The relative default value is displayed in instance settings page');
+
+      // Check if default_date has been stored successfully.
+      $config_entity = $this->config('field.field.node.date_content.' . $field_name)
+        ->get();
+      $this->assertEqual($config_entity['default_value'][0], [
+        'default_date_type' => 'relative',
+        'default_date' => '+90 days',
+      ], 'Default value has been stored successfully');
+
+      // Clear field cache in order to avoid stale cache values.
+      \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+      // Create a new node to check that datetime field default value is +90
+      // days.
+      $new_node = Node::create(['type' => 'date_content']);
+      $expected_date = new DrupalDateTime('+90 days', drupal_get_user_timezone());
+      $this->assertEqual($new_node->get($field_name)
+        ->offsetGet(0)->value, $expected_date->format(DATETIME_DATE_STORAGE_FORMAT));
+
+      // Remove default value.
+      $field_edit = [
+        'default_value_input[default_date_type]' => '',
+      ];
+      $this->drupalPostForm('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name, $field_edit, t('Save settings'));
+
+      // Check that default value is selected in default value form.
+      $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name);
+      $this->assertOptionSelected('edit-default-value-input-default-date-type', '', 'The default value is selected in instance settings page');
+      $this->assertFieldByName('default_value_input[default_date]', '', 'The relative default value is empty in instance settings page');
+
+      // Check if default_date has been stored successfully.
+      $config_entity = $this->config('field.field.node.date_content.' . $field_name)
+        ->get();
+      $this->assertTrue(empty($config_entity['default_value']), 'Empty default value has been stored successfully');
+
+      // Clear field cache in order to avoid stale cache values.
+      \Drupal::entityManager()->clearCachedFieldDefinitions();
+
+      // Create a new node to check that datetime field default value is not
+      // set.
+      $new_node = Node::create(['type' => 'date_content']);
+      $this->assertNull($new_node->get($field_name)->value, 'Default value is not set');
+    }
+  }
+
+  /**
+   * Test that invalid values are caught and marked as invalid.
+   */
+  public function testInvalidField() {
+    // Change the field to a datetime field.
+    $this->fieldStorage->setSetting('datetime_type', 'datetime');
+    $this->fieldStorage->save();
+    $field_name = $this->fieldStorage->getName();
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+    $this->assertFieldByName("{$field_name}[0][value][date]", '', 'Date element found.');
+    $this->assertFieldByName("{$field_name}[0][value][time]", '', 'Time element found.');
+
+    // Submit invalid dates and ensure they is not accepted.
+    $date_value = '';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => '12:00:00',
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', 'Empty date value has been caught.');
+
+    $date_value = 'aaaa-12-01';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => '00:00:00',
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid year value %date has been caught.', ['%date' => $date_value]));
+
+    $date_value = '2012-75-01';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => '00:00:00',
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid month value %date has been caught.', ['%date' => $date_value]));
+
+    $date_value = '2012-12-99';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => '00:00:00',
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid day value %date has been caught.', ['%date' => $date_value]));
+
+    $date_value = '2012-12-01';
+    $time_value = '';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => $time_value,
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', 'Empty time value has been caught.');
+
+    $date_value = '2012-12-01';
+    $time_value = '49:00:00';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => $time_value,
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid hour value %time has been caught.', ['%time' => $time_value]));
+
+    $date_value = '2012-12-01';
+    $time_value = '12:99:00';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => $time_value,
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid minute value %time has been caught.', ['%time' => $time_value]));
+
+    $date_value = '2012-12-01';
+    $time_value = '12:15:99';
+    $edit = [
+      "{$field_name}[0][value][date]" => $date_value,
+      "{$field_name}[0][value][time]" => $time_value,
+    ];
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    $this->assertText('date is invalid', format_string('Invalid second value %time has been caught.', ['%time' => $time_value]));
+  }
+
+  /**
+   * Tests that 'Date' field storage setting form is disabled if field has data.
+   */
+  public function testDateStorageSettings() {
+    // Create a test content type.
+    $this->drupalCreateContentType(['type' => 'date_content']);
+
+    // Create a field storage with settings to validate.
+    $field_name = Unicode::strtolower($this->randomMachineName());
+    $field_storage = FieldStorageConfig::create([
+      'field_name' => $field_name,
+      'entity_type' => 'node',
+      'type' => 'datetime',
+      'settings' => [
+        'datetime_type' => 'date',
+      ],
+    ]);
+    $field_storage->save();
+    $field = FieldConfig::create([
+      'field_storage' => $field_storage,
+      'field_name' => $field_name,
+      'bundle' => 'date_content',
+    ]);
+    $field->save();
+
+    entity_get_form_display('node', 'date_content', 'default')
+      ->setComponent($field_name, [
+        'type' => 'datetime_default',
+      ])
+      ->save();
+    $edit = [
+      'title[0][value]' => $this->randomString(),
+      'body[0][value]' => $this->randomString(),
+      $field_name . '[0][value][date]' => '2016-04-01',
+    ];
+    $this->drupalPostForm('node/add/date_content', $edit, t('Save'));
+    $this->drupalGet('admin/structure/types/manage/date_content/fields/node.date_content.' . $field_name . '/storage');
+    $result = $this->xpath("//*[@id='edit-settings-datetime-type' and contains(@disabled, 'disabled')]");
+    $this->assertEqual(count($result), 1, "Changing datetime setting is disabled.");
+    $this->assertText('There is data for this field in the database. The field settings can no longer be changed.');
+  }
+
+}

core/modules/datetime/tests/src/Kernel/DateTimeFormInjectionTest.php

@@ -0,0 +1,113 @@
+<?php
+
+namespace Drupal\Tests\datetime\Kernel;
+
+use Drupal\Core\Datetime\DrupalDateTime;
+use Drupal\Core\DependencyInjection\DependencySerializationTrait;
+use Drupal\Core\Form\FormInterface;
+use Drupal\Core\Form\FormState;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests serializing a form with an injected datetime instance.
+ *
+ * @group datetime
+ */
+class DateTimeFormInjectionTest extends KernelTestBase implements FormInterface {
+
+  use DependencySerializationTrait;
+
+  /**
+   * A Dblog logger instance.
+   *
+   * @var \Psr\Log\LoggerInterface
+   */
+  protected $logger;
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = ['system', 'datetime'];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->installSchema('system', ['key_value_expire', 'sequences']);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'datetime_test_injection_form';
+  }
+
+  /**
+   * Process callback.
+   *
+   * @param array $element
+   *   Form element.
+   *
+   * @return array
+   *   Processed element.
+   */
+  public function process($element) {
+    return $element;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form['datelist_element'] = [
+      '#title' => 'datelist test',
+      '#type' => 'datelist',
+      '#default_value' => new DrupalDateTime('2000-01-01 00:00:00'),
+      '#date_part_order' => [
+        'month',
+        'day',
+        'year',
+        'hour',
+        'minute', 'ampm',
+      ],
+      '#date_text_parts' => ['year'],
+      '#date_year_range' => '2010:2020',
+      '#date_increment' => 15,
+    ];
+    $form['#process'][] = [$this, 'process'];
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {}
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $this->assertTrue(TRUE);
+    $form_state->setRebuild();
+  }
+
+  /**
+   * Tests custom string injection serialization.
+   */
+  public function testDatetimeSerialization() {
+    $form_state = new FormState();
+    $form_state->setRequestMethod('POST');
+    $form_state->setCached();
+    $form_builder = $this->container->get('form_builder');
+    $form_id = $form_builder->getFormId($this, $form_state);
+    $form = $form_builder->retrieveForm($form_id, $form_state);
+    $form_builder->prepareForm($form_id, $form, $form_state);
+    $form_builder->processForm($form_id, $form, $form_state);
+  }
+
+}

core/modules/datetime/tests/src/Kernel/DateTimeItemTest.php

@@ -4,6 +4,7 @@ namespace Drupal\Tests\datetime\Kernel;
 
 use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\Core\Field\FieldItemInterface;
+use Drupal\datetime\Plugin\Field\FieldType\DateTimeItem;
 use Drupal\entity_test\Entity\EntityTest;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\Tests\field\Kernel\FieldKernelTestBase;
@@ -16,61 +17,116 @@ use Drupal\field\Entity\FieldStorageConfig;
  */
 class DateTimeItemTest extends FieldKernelTestBase {
 
+  /**
+   * A field storage to use in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldStorageConfig
+   */
+  protected $fieldStorage;
+
+  /**
+   * The field used in this test class.
+   *
+   * @var \Drupal\field\Entity\FieldConfig
+   */
+  protected $field;
+
   /**
    * Modules to enable.
    *
    * @var array
    */
-  public static $modules = array('datetime');
+  public static $modules = ['datetime'];
 
   protected function setUp() {
     parent::setUp();
 
     // Create a field with settings to validate.
-    $field_storage = FieldStorageConfig::create(array(
+    $this->fieldStorage = FieldStorageConfig::create([
       'field_name' => 'field_datetime',
       'type' => 'datetime',
       'entity_type' => 'entity_test',
-      'settings' => array('datetime_type' => 'date'),
-    ));
-    $field_storage->save();
-    $field = FieldConfig::create([
-      'field_storage' => $field_storage,
-      'bundle' => 'entity_test',
-      'settings' => array(
-        'default_value' => 'blank',
-      ),
+      'settings' => ['datetime_type' => DateTimeItem::DATETIME_TYPE_DATETIME],
     ]);
-    $field->save();
+    $this->fieldStorage->save();
+    $this->field = FieldConfig::create([
+      'field_storage' => $this->fieldStorage,
+      'bundle' => 'entity_test',
+      'settings' => [
+        'default_value' => 'blank',
+      ],
+    ]);
+    $this->field->save();
   }
 
   /**
-   * Tests using entity fields of the date field type.
+   * Tests using entity fields of the datetime field type.
    */
-  public function testDateTimeItem() {
+  public function testDateTime() {
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATETIME);
+    $this->fieldStorage->save();
+
     // Verify entity creation.
     $entity = EntityTest::create();
-    $value = '2014-01-01T20:00:00Z';
+    $value = '2014-01-01T20:00:00';
     $entity->field_datetime = $value;
     $entity->name->value = $this->randomMachineName();
-    $entity->save();
+    $this->entityValidateAndSave($entity);
 
     // Verify entity has been created properly.
     $id = $entity->id();
-    $entity = entity_load('entity_test', $id);
+    $entity = EntityTest::load($id);
     $this->assertTrue($entity->field_datetime instanceof FieldItemListInterface, 'Field implements interface.');
     $this->assertTrue($entity->field_datetime[0] instanceof FieldItemInterface, 'Field item implements interface.');
     $this->assertEqual($entity->field_datetime->value, $value);
     $this->assertEqual($entity->field_datetime[0]->value, $value);
 
     // Verify changing the date value.
-    $new_value = $this->randomMachineName();
+    $new_value = '2016-11-04T00:21:00';
     $entity->field_datetime->value = $new_value;
     $this->assertEqual($entity->field_datetime->value, $new_value);
 
     // Read changed entity and assert changed values.
-    $entity->save();
-    $entity = entity_load('entity_test', $id);
+    $this->entityValidateAndSave($entity);
+    $entity = EntityTest::load($id);
+    $this->assertEqual($entity->field_datetime->value, $new_value);
+
+    // Test the generateSampleValue() method.
+    $entity = EntityTest::create();
+    $entity->field_datetime->generateSampleItems();
+    $this->entityValidateAndSave($entity);
+  }
+
+  /**
+   * Tests using entity fields of the date field type.
+   */
+  public function testDateOnly() {
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATE);
+    $this->fieldStorage->save();
+
+    // Verify entity creation.
+    $entity = EntityTest::create();
+    $value = '2014-01-01';
+    $entity->field_datetime = $value;
+    $entity->name->value = $this->randomMachineName();
+    $this->entityValidateAndSave($entity);
+
+    // Verify entity has been created properly.
+    $id = $entity->id();
+    $entity = EntityTest::load($id);
+    $this->assertTrue($entity->field_datetime instanceof FieldItemListInterface, 'Field implements interface.');
+    $this->assertTrue($entity->field_datetime[0] instanceof FieldItemInterface, 'Field item implements interface.');
+    $this->assertEqual($entity->field_datetime->value, $value);
+    $this->assertEqual($entity->field_datetime[0]->value, $value);
+
+    // Verify changing the date value.
+    $new_value = '2016-11-04';
+    $entity->field_datetime->value = $new_value;
+    $this->assertEqual($entity->field_datetime->value, $new_value);
+
+    // Read changed entity and assert changed values.
+    $this->entityValidateAndSave($entity);
+    $entity = EntityTest::load($id);
     $this->assertEqual($entity->field_datetime->value, $new_value);
 
     // Test the generateSampleValue() method.
@@ -83,24 +139,52 @@ class DateTimeItemTest extends FieldKernelTestBase {
    * Tests DateTimeItem::setValue().
    */
   public function testSetValue() {
+    // Test a date+time field.
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATETIME);
+    $this->fieldStorage->save();
+
     // Test DateTimeItem::setValue() using string.
     $entity = EntityTest::create();
-    $value = '2014-01-01T20:00:00Z';
+    $value = '2014-01-01T20:00:00';
     $entity->get('field_datetime')->set(0, $value);
-    $entity->save();
+    $this->entityValidateAndSave($entity);
     // Load the entity and ensure the field was saved correctly.
     $id = $entity->id();
-    $entity = entity_load('entity_test', $id);
+    $entity = EntityTest::load($id);
     $this->assertEqual($entity->field_datetime[0]->value, $value, 'DateTimeItem::setValue() works with string value.');
 
     // Test DateTimeItem::setValue() using property array.
     $entity = EntityTest::create();
-    $value = '2014-01-01T20:00:00Z';
+    $value = '2014-01-01T20:00:00';
     $entity->set('field_datetime', $value);
-    $entity->save();
+    $this->entityValidateAndSave($entity);
     // Load the entity and ensure the field was saved correctly.
     $id = $entity->id();
-    $entity = entity_load('entity_test', $id);
+    $entity = EntityTest::load($id);
+    $this->assertEqual($entity->field_datetime[0]->value, $value, 'DateTimeItem::setValue() works with array value.');
+
+    // Test a date-only field.
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATE);
+    $this->fieldStorage->save();
+
+    // Test DateTimeItem::setValue() using string.
+    $entity = EntityTest::create();
+    $value = '2014-01-01';
+    $entity->get('field_datetime')->set(0, $value);
+    $this->entityValidateAndSave($entity);
+    // Load the entity and ensure the field was saved correctly.
+    $id = $entity->id();
+    $entity = EntityTest::load($id);
+    $this->assertEqual($entity->field_datetime[0]->value, $value, 'DateTimeItem::setValue() works with string value.');
+
+    // Test DateTimeItem::setValue() using property array.
+    $entity = EntityTest::create();
+    $value = '2014-01-01';
+    $entity->set('field_datetime', $value);
+    $this->entityValidateAndSave($entity);
+    // Load the entity and ensure the field was saved correctly.
+    $id = $entity->id();
+    $entity = EntityTest::load($id);
     $this->assertEqual($entity->field_datetime[0]->value, $value, 'DateTimeItem::setValue() works with array value.');
   }
 
@@ -108,15 +192,32 @@ class DateTimeItemTest extends FieldKernelTestBase {
    * Tests setting the value of the DateTimeItem directly.
    */
   public function testSetValueProperty() {
-    // Test Date::setValue().
+    // Test Date::setValue() with a date+time field.
+    // Test a date+time field.
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATETIME);
+    $this->fieldStorage->save();
     $entity = EntityTest::create();
-    $value = '2014-01-01T20:00:00Z';
+    $value = '2014-01-01T20:00:00';
 
     $entity->set('field_datetime', $value);
-    $entity->save();
+    $this->entityValidateAndSave($entity);
     // Load the entity and ensure the field was saved correctly.
     $id = $entity->id();
-    $entity = entity_load('entity_test', $id);
+    $entity = EntityTest::load($id);
+    $this->assertEqual($entity->field_datetime[0]->value, $value, '"Value" property can be set directly.');
+
+    // Test Date::setValue() with a date-only field.
+    // Test a date+time field.
+    $this->fieldStorage->setSetting('datetime_type', DateTimeItem::DATETIME_TYPE_DATE);
+    $this->fieldStorage->save();
+    $entity = EntityTest::create();
+    $value = '2014-01-01';
+
+    $entity->set('field_datetime', $value);
+    $this->entityValidateAndSave($entity);
+    // Load the entity and ensure the field was saved correctly.
+    $id = $entity->id();
+    $entity = EntityTest::load($id);
     $this->assertEqual($entity->field_datetime[0]->value, $value, '"Value" property can be set directly.');
   }
 

core/modules/datetime/tests/src/Unit/Plugin/migrate/field/d6/DateFieldTest.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Drupal\Tests\datetime\Unit\Plugin\migrate\field\d6;
+
+use Drupal\datetime\Plugin\migrate\field\d6\DateField;
+use Drupal\migrate\MigrateException;
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * @group migrate
+ */
+class DateFieldTest extends UnitTestCase {
+
+  /**
+   * @var \Drupal\migrate_drupal\Plugin\MigrateFieldInterface
+   */
+  protected $plugin;
+
+  /**
+   * @var \Drupal\migrate\Plugin\MigrationInterface
+   */
+  protected $migration;
+
+  /**
+   * Tests an Exception is thrown when the field type is not a known date type.
+   */
+  public function testUnknownDateType() {
+    $this->migration = $this->prophesize('Drupal\migrate\Plugin\MigrationInterface')->reveal();
+    $this->plugin = new DateField([], '', []);
+
+    $this->setExpectedException(MigrateException::class, "Field field_date of type 'timestamp' is an unknown date field type.");
+    $this->plugin->processFieldValues($this->migration, 'field_date', ['type' => 'timestamp']);
+  }
+
+}