diff --git a/core/modules/datetime_range/src/Tests/DateRangeFieldTest.php b/core/modules/datetime_range/src/Tests/DateRangeFieldTest.php
index 2afb5f5..189af1f 100644
--- a/core/modules/datetime_range/src/Tests/DateRangeFieldTest.php
+++ b/core/modules/datetime_range/src/Tests/DateRangeFieldTest.php
@@ -140,6 +140,10 @@ public function testDateRangeField() {
       ]));
       $this->assertText(' THESEPARATOR ', 'Found proper separator');
 
+      // Verify that hook_entity_prepare_view can add attributes.
+      $this->drupalGet('entity_test/' . $id);
+      $this->assertFieldByXPath('//div[@data-field-item-attr="foobar"]');
+
       // Verify that the plain formatter works.
       $this->displayOptions['type'] = 'daterange_plain';
       $this->displayOptions['settings'] = $this->defaultSettings;
@@ -203,6 +207,10 @@ public function testDateRangeField() {
       ]));
       $this->assertNoText(' THESEPARATOR ', 'Separator not found on page');
 
+      // Verify that hook_entity_prepare_view can add attributes.
+      $this->drupalGet('entity_test/' . $id);
+      $this->assertFieldByXPath('//time[@data-field-item-attr="foobar"]');
+
       $this->displayOptions['type'] = 'daterange_plain';
       $this->displayOptions['settings'] = $this->defaultSettings;
       entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
@@ -289,6 +297,10 @@ public function testDatetimeRangeField() {
     $this->assertFieldByXPath('//time[@datetime="' . $end_expected_iso . '"]', $end_expected, new FormattableMarkup('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => 'long', '%expected' => $end_expected, '%expected_iso' => $end_expected_iso]));
     $this->assertText(' THESEPARATOR ', 'Found proper separator');
 
+    // Verify that hook_entity_prepare_view can add attributes.
+    $this->drupalGet('entity_test/' . $id);
+    $this->assertFieldByXPath('//div[@data-field-item-attr="foobar"]');
+
     // Verify that the plain formatter works.
     $this->displayOptions['type'] = 'daterange_plain';
     $this->displayOptions['settings'] = $this->defaultSettings;
@@ -360,6 +372,10 @@ public function testDatetimeRangeField() {
     $this->assertFieldByXPath('//time[@datetime="' . $start_expected_iso . '"]', $start_expected, new FormattableMarkup('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => 'long', '%expected' => $start_expected, '%expected_iso' => $start_expected_iso]));
     $this->assertNoText(' THESEPARATOR ', 'Separator not found on page');
 
+    // Verify that hook_entity_prepare_view can add attributes.
+    $this->drupalGet('entity_test/' . $id);
+    $this->assertFieldByXPath('//time[@data-field-item-attr="foobar"]');
+
     $this->displayOptions['type'] = 'daterange_plain';
     $this->displayOptions['settings'] = $this->defaultSettings;
     entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
@@ -440,6 +456,10 @@ public function testAlldayRangeField() {
     $this->assertFieldByXPath('//time[@datetime="' . $end_expected_iso . '"]', $end_expected, new FormattableMarkup('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => 'long', '%expected' => $end_expected, '%expected_iso' => $end_expected_iso]));
     $this->assertText(' THESEPARATOR ', 'Found proper separator');
 
+    // Verify that hook_entity_prepare_view can add attributes.
+    $this->drupalGet('entity_test/' . $id);
+    $this->assertFieldByXPath('//div[@data-field-item-attr="foobar"]');
+
     // Verify that the plain formatter works.
     $this->displayOptions['type'] = 'daterange_plain';
     $this->displayOptions['settings'] = $this->defaultSettings;
@@ -513,6 +533,10 @@ public function testAlldayRangeField() {
     $this->assertFieldByXPath('//time[@datetime="' . $end_expected_iso . '"]', $end_expected, new FormattableMarkup('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', ['%value' => 'long', '%expected' => $end_expected, '%expected_iso' => $end_expected_iso]));
     $this->assertText(' THESEPARATOR ', 'Found proper separator');
 
+    // Verify that hook_entity_prepare_view can add attributes.
+    $this->drupalGet('entity_test/' . $id);
+    $this->assertFieldByXPath('//div[@data-field-item-attr="foobar"]');
+
     $this->displayOptions['type'] = 'daterange_plain';
     entity_get_display($this->field->getTargetEntityTypeId(), $this->field->getTargetBundle(), 'full')
       ->setComponent($field_name, $this->displayOptions)
diff --git a/core/modules/system/tests/modules/entity_test/entity_test.module b/core/modules/system/tests/modules/entity_test/entity_test.module
index 453bdf1..b0c8cbf 100644
--- a/core/modules/system/tests/modules/entity_test/entity_test.module
+++ b/core/modules/system/tests/modules/entity_test/entity_test.module
@@ -674,14 +674,25 @@ function _entity_test_record_hooks($hook, $data) {
  * Implements hook_entity_prepare_view().
  */
 function entity_test_entity_prepare_view($entity_type, array $entities, array $displays) {
-  // Add a dummy field item attribute on field_test_text if it exists.
   if ($entity_type == 'entity_test') {
     foreach ($entities as $entity) {
+      /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
+
+      // Add a dummy field item attribute on field_test_text if it exists.
       if ($entity->hasField('field_test_text') && $displays[$entity->bundle()]->getComponent('field_test_text')) {
         foreach ($entity->get('field_test_text') as $item) {
           $item->_attributes += array('data-field-item-attr' => 'foobar');
         }
       }
+
+      // Add a dummy field item attribute on daterange fields if they exist.
+      $fields = $entity->getFieldDefinitions();
+      foreach ($fields as $field) {
+        if ($field->getType() === 'daterange') {
+          $item = $entity->get($field->getName());
+          $item->_attributes += array('data-field-item-attr' => 'foobar');
+        }
+      }
     }
   }
 }