diff --git a/core/modules/datetime/config/schema/datetime.schema.yml b/core/modules/datetime/config/schema/datetime.schema.yml
index aade88f..e627ce0 100644
--- a/core/modules/datetime/config/schema/datetime.schema.yml
+++ b/core/modules/datetime/config/schema/datetime.schema.yml
@@ -92,7 +92,7 @@ field.storage_settings.daterange:
   type: mapping
   label: 'Daterange settings'
   mapping:
-    datetime_type:
+    daterange_type:
       type: string
       label: 'Date type'
 
diff --git a/core/modules/datetime/src/DateTimeComputed.php b/core/modules/datetime/src/DateTimeComputed.php
index 6939994..49f0512 100644
--- a/core/modules/datetime/src/DateTimeComputed.php
+++ b/core/modules/datetime/src/DateTimeComputed.php
@@ -40,10 +40,12 @@ public function getValue($langcode = NULL) {
       return $this->date;
     }
 
+    /** @var \Drupal\Core\Field\FieldItemBase $item */
     $item = $this->getParent();
     $value = $item->{($this->definition->getSetting('date source'))};
+    $type = $item->getFieldDefinition()->getType();
 
-    $storage_format = $item->getFieldDefinition()->getSetting('datetime_type') == 'date' ? DATETIME_DATE_STORAGE_FORMAT : DATETIME_DATETIME_STORAGE_FORMAT;
+    $storage_format = $item->getFieldDefinition()->getSetting($type . '_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()) {
diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeCustomFormatter.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeCustomFormatter.php
index 3586fb7..a0c107f 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeCustomFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeCustomFormatter.php
@@ -23,9 +23,9 @@ class DateRangeCustomFormatter extends DateRangeFormatterBase {
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'date_format' => DATETIME_DATETIME_STORAGE_FORMAT,
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
@@ -80,12 +80,12 @@ protected function formatDate($date) {
   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;
   }
@@ -98,7 +98,7 @@ public function settingsSummary() {
 
     $date = DrupalDateTime::createFromTimestamp(REQUEST_TIME);
     $this->setTimeZone($date);
-    $summary[] = $this->t('Format: @display', array('@display' => $this->formatDate($date)));
+    $summary[] = $this->t('Format: @display', ['@display' => $this->formatDate($date)]);
 
     return $summary;
   }
diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeDefaultFormatter.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeDefaultFormatter.php
index e239936..dd0a19d 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeDefaultFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeDefaultFormatter.php
@@ -23,9 +23,9 @@ class DateRangeDefaultFormatter extends DateRangeFormatterBase {
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'format_type' => 'medium',
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
@@ -114,13 +114,13 @@ public function settingsForm(array $form, FormStateInterface $form_state) {
       $options[$type] = $type_info->label() . ' (' . $format . ')';
     }
 
-    $form['format_type'] = array(
+    $form['format_type'] = [
       '#type' => 'select',
       '#title' => t('Date format'),
       '#description' => $this->t('Choose a format for displaying the dates. 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;
   }
@@ -133,7 +133,7 @@ public function settingsSummary() {
 
     $date = DrupalDateTime::createFromTimestamp(REQUEST_TIME);
     $this->setTimeZone($date);
-    $summary[] = $this->t('Format: @display', array('@display' => $this->formatDate($date)));
+    $summary[] = $this->t('Format: @display', ['@display' => $this->formatDate($date)]);
 
     return $summary;
   }
diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeFormatterBase.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeFormatterBase.php
index f0b6b04..9db9053 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeFormatterBase.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateRangeFormatterBase.php
@@ -81,10 +81,10 @@ public static function create(ContainerInterface $container, array $configuratio
    * {@inheritdoc}
    */
   public static function defaultSettings() {
-    return array(
+    return [
       'separator' => '-',
       'timezone_override' => '',
-    ) + parent::defaultSettings();
+    ] + parent::defaultSettings();
   }
 
   /**
@@ -93,20 +93,20 @@ public static function defaultSettings() {
   public function settingsForm(array $form, FormStateInterface $form_state) {
     $form = parent::settingsForm($form, $form_state);
 
-    $form['separator'] = array(
+    $form['separator'] = [
       '#type' => 'textfield',
       '#title' => $this->t('Date separator'),
       '#description' => $this->t('The string to separate the start and end dates'),
       '#default_value' => $this->getSetting('separator'),
-    );
+    ];
 
-    $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;
   }
@@ -118,11 +118,11 @@ public function settingsSummary() {
     $summary = parent::settingsSummary();
 
     if ($separator = $this->getSetting('separator')) {
-      $summary[] = $this->t('Separator: %separator', array('%separator' => $separator));
+      $summary[] = $this->t('Separator: %separator', ['%separator' => $separator]);
     }
 
     if ($override = $this->getSetting('timezone_override')) {
-      $summary[] = $this->t('Time zone: @timezone', array('@timezone' => $override));
+      $summary[] = $this->t('Time zone: @timezone', ['@timezone' => $override]);
     }
 
     return $summary;
diff --git a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
index 1f9c6bb..2fedb5a 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
@@ -30,31 +30,31 @@ public function defaultValuesForm(array &$form, FormStateInterface $form_state)
     if (empty($this->getFieldDefinition()->getDefaultValueCallback())) {
       $default_value = $this->getFieldDefinition()->getDefaultValueLiteral();
 
-      $element = array(
-        '#parents' => array('default_value_input'),
-        'default_date_type' => array(
+      $element = [
+        '#parents' => ['default_value_input'],
+        'default_date_type' => [
           '#type' => 'select',
           '#title' => t('Default dates'),
           '#description' => t('Set a default value for these dates.'),
           '#default_value' => isset($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 $element;
     }
@@ -65,7 +65,7 @@ public function defaultValuesForm(array &$form, FormStateInterface $form_state)
    */
   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 @@ public function defaultValuesFormValidate(array $element, array &$form, FormStat
    * {@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 [];
   }
 
   /**
@@ -100,14 +100,14 @@ public static function processDefaultValue($default_value, FieldableEntityInterf
       // 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 = [
+        [
           'start_value' => $value,
           'start_date' => $date,
           'end_value' => $value,
           'end_date' => $date,
-        )
-      );
+        ],
+      ];
     }
     return $default_value;
   }
diff --git a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeItem.php b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeItem.php
index 6aca3b2..3e8aafa 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeItem.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldType/DateRangeItem.php
@@ -26,9 +26,9 @@ class DateRangeItem extends FieldItemBase {
    * {@inheritdoc}
    */
   public static function defaultStorageSettings() {
-    return array(
-      'daterange_type' => 'daterange',
-    ) + parent::defaultStorageSettings();
+    return [
+      'daterange_type' => 'datetime',
+    ] + parent::defaultStorageSettings();
   }
 
   /**
@@ -74,43 +74,43 @@ public static function propertyDefinitions(FieldStorageDefinitionInterface $fiel
    * {@inheritdoc}
    */
   public static function schema(FieldStorageDefinitionInterface $field_definition) {
-    return array(
-      'columns' => array(
-        'start_value' => array(
+    return [
+      'columns' => [
+        'start_value' => [
           'description' => 'The start date value.',
           'type' => 'varchar',
           'length' => 20,
-        ),
-        'end_value' => array(
+        ],
+        'end_value' => [
           'description' => 'The end date value.',
           'type' => 'varchar',
           'length' => 20,
-        ),
-      ),
-      'indexes' => array(
-        'start_value' => array('start_value'),
-        'end_value' => array('end_value'),
-      ),
-    );
+        ],
+      ],
+      'indexes' => [
+        'start_value' => ['start_value'],
+        'end_value' => ['end_value'],
+      ],
+    ];
   }
 
   /**
    * {@inheritdoc}
    */
   public function storageSettingsForm(array &$form, FormStateInterface $form_state, $has_data) {
-    $element = array();
+    $element = [];
 
-    $element['datetime_type'] = array(
+    $element['daterange_type'] = [
       '#type' => 'select',
       '#title' => $this->t('Date type'),
       '#description' => $this->t('Choose the type of date to create.'),
-      '#default_value' => $this->getSetting('datetime_type'),
-      '#options' => array(
+      '#default_value' => $this->getSetting('daterange_type'),
+      '#options' => [
         static::DATERANGE_TYPE_DATETIME => t('Date and time'),
         static::DATERANGE_TYPE_DATE => t('Date only'),
-      ),
+      ],
       '#disabled' => $has_data,
-    );
+    ];
 
     return $element;
   }
diff --git a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDatelistWidget.php b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDatelistWidget.php
index ffc54f5..4dea3e7 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDatelistWidget.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDatelistWidget.php
@@ -48,6 +48,7 @@ public function formElement(FieldItemListInterface $items, $delta, array $elemen
 
     // Set up the date part order array.
     switch ($date_order) {
+      default:
       case 'YMD':
         $date_part_order = array('year', 'month', 'day');
         break;
@@ -61,29 +62,30 @@ public function formElement(FieldItemListInterface $items, $delta, array $elemen
         break;
     }
     switch ($time_type) {
-       case '24':
-         $date_part_order = array_merge($date_part_order, array('hour', 'minute'));
-         break;
+      default:
+      case '24':
+        $date_part_order = array_merge($date_part_order, array('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, array('hour', 'minute', 'ampm'));
+        break;
 
-       case 'none':
-         break;
+      case 'none':
+        break;
     }
 
-    $element['start_value'] = array(
+    $element['start_value'] = [
       '#type' => 'datelist',
       '#date_increment' => $increment,
       '#date_part_order' => $date_part_order,
-    ) + $element['start_value'];
+    ] + $element['start_value'];
 
-    $element['end_value'] = array(
-        '#type' => 'datelist',
-        '#date_increment' => $increment,
-        '#date_part_order' => $date_part_order,
-      ) + $element['end_value'];
+    $element['end_value'] = [
+      '#type' => 'datelist',
+      '#date_increment' => $increment,
+      '#date_part_order' => $date_part_order,
+    ] + $element['end_value'];
 
     return $element;
   }
diff --git a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php
index e304b1f..20228a6 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php
@@ -59,8 +59,6 @@ public static function create(ContainerInterface $container, array $configuratio
   public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
     $element = parent::formElement($items, $delta, $element, $form, $form_state);
 
-    debug([$this->getSettings()]);
-
     // Identify the type of date and time elements to use.
     switch ($this->getFieldSetting('daterange_type')) {
       case DateRangeItem::DATERANGE_TYPE_DATE:
diff --git a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeWidgetBase.php b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeWidgetBase.php
index 28c7e12..d694c28 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeWidgetBase.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldWidget/DateRangeWidgetBase.php
@@ -56,20 +56,20 @@ public function formElement(FieldItemListInterface $items, $delta, array $elemen
       }
       $start_date->setTimezone(new \DateTimeZone($element['start_value']['#date_timezone']));
       $element['start_value']['#default_value'] = $start_date;
+    }
 
-      if ($items[$delta]->end_date) {
-        /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
-        $end_date = $items[$delta]->end_date;
-        // The date was created and verified during field_load(), so it is safe to
-        // use without further inspection.
-        if ($this->getFieldSetting('daterange_type') == DateRangeItem::DATERANGE_TYPE_DATE) {
-          // A date without time will pick up the current time, use the default
-          // time.
-          datetime_date_default_time($end_date);
-        }
-        $end_date->setTimezone(new \DateTimeZone($element['end_value']['#date_timezone']));
-        $element['end_value']['#default_value'] = $end_date;
+    if ($items[$delta]->end_date) {
+      /** @var \Drupal\Core\Datetime\DrupalDateTime $start_date */
+      $end_date = $items[$delta]->end_date;
+      // The date was created and verified during field_load(), so it is safe to
+      // use without further inspection.
+      if ($this->getFieldSetting('daterange_type') == DateRangeItem::DATERANGE_TYPE_DATE) {
+        // A date without time will pick up the current time, use the default
+        // time.
+        datetime_date_default_time($end_date);
       }
+      $end_date->setTimezone(new \DateTimeZone($element['end_value']['#date_timezone']));
+      $element['end_value']['#default_value'] = $end_date;
     }
 
     return $element;
@@ -101,16 +101,29 @@ public function massageFormValues(array $values, array $form, FormStateInterface
         // Adjust the date for storage.
         $start_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
         $item['start_value'] = $start_date->format($format);
+      }
+
+      if (!empty($item['end_value']) && $item['end_value'] instanceof DrupalDateTime) {
+        /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
+        $end_date = $item['end_value'];
+        switch ($this->getFieldSetting('daterange_type')) {
+          case DateRangeItem::DATERANGE_TYPE_DATE:
+            // If this is a date-only field, set it to the default time so the
+            // timezone conversion can be reversed.
+            datetime_date_default_time($end_date);
+            $format = DATETIME_DATE_STORAGE_FORMAT;
+            break;
 
-        if (!empty($item['end_value']) && $item['end_value'] instanceof DrupalDateTime) {
-          /** @var \Drupal\Core\Datetime\DrupalDateTime $end_date */
-          $end_date = $item['end_value'];
-          // Adjust the date for storage.
-          $end_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
-          $item['end_value'] = $end_date->format($format);
+          default:
+            $format = DATETIME_DATETIME_STORAGE_FORMAT;
+            break;
         }
+        // Adjust the date for storage.
+        $end_date->setTimezone(new \DateTimezone(DATETIME_STORAGE_TIMEZONE));
+        $item['end_value'] = $end_date->format($format);
       }
     }
+
     return $values;
   }