From b6890803c1b3448f245fb1948e2494b7de24739d Mon Sep 17 00:00:00 2001
From: Alex Pott <alex.a.pott@googlemail.com>
Date: Mon, 12 Feb 2018 10:57:12 +0000
Subject: [PATCH] Issue #2942497 by scott_euser, timmillwood, malcomio, Berdir:
 Using content moderation block in preview mode causes EntityStorageException

---
 .../content_moderation/src/EntityOperations.php  |  3 +++
 .../tests/src/Functional/ModerationFormTest.php  | 16 ++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/core/modules/content_moderation/src/EntityOperations.php b/core/modules/content_moderation/src/EntityOperations.php
index 2da246239c8..e2688601df5 100644
--- a/core/modules/content_moderation/src/EntityOperations.php
+++ b/core/modules/content_moderation/src/EntityOperations.php
@@ -269,6 +269,9 @@ class EntityOperations implements ContainerInjectionInterface {
     if (!$this->moderationInfo->isModeratedEntity($entity)) {
       return;
     }
+    if (isset($entity->in_preview) && $entity->in_preview) {
+      return;
+    }
     // If the component is not defined for this display, we have nothing to do.
     if (!$display->getComponent('content_moderation_control')) {
       return;
diff --git a/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php b/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
index 4b483584e49..bb9e92d6ea5 100644
--- a/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
+++ b/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
@@ -4,6 +4,7 @@ namespace Drupal\Tests\content_moderation\Functional;
 
 use Drupal\Core\Entity\Entity\EntityFormDisplay;
 use Drupal\workflows\Entity\Workflow;
+use Drupal\Core\Url;
 
 /**
  * Tests the moderation form, specifically on nodes.
@@ -80,6 +81,21 @@ class ModerationFormTest extends ModerationStateTestBase {
     $this->assertResponse(200);
     $this->assertField('edit-new-state', 'The node view page has a moderation form.');
 
+    // Preview the draft.
+    $this->drupalPostForm($edit_path, [
+      'body[0][value]' => 'Second version of the content.',
+      'moderation_state[0][state]' => 'draft',
+    ], t('Preview'));
+
+    // The preview view should not have a moderation form.
+    $preview_url = Url::fromRoute('entity.node.preview', [
+      'node_preview' => $node->uuid(),
+      'view_mode_id' => 'full',
+    ]);
+    $this->assertResponse(200);
+    $this->assertUrl($preview_url);
+    $this->assertNoField('edit-new-state', 'The node preview page has no moderation form.');
+
     // The latest version page should not show, because there is still no
     // pending revision.
     $this->drupalGet($latest_version_path);