Issue #3167126 by ranjith_kumar_k_u, rpayanm, amateescu, mheip, CedricL,...

Issue #3167126 by ranjith_kumar_k_u, rpayanm, amateescu, mheip, CedricL, smustgrave: Call to a member function getDisplayname() on null in WorkspaceListBuilder.php

core/modules/workspaces/src/WorkspaceListBuilder.php

@@ -10,6 +10,7 @@
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Url;
+use Drupal\user\UserInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -121,7 +122,9 @@ public function buildRow(EntityInterface $entity) {
           '#url' => $entity->toUrl(),
         ],
       ],
-      'owner' => $entity->getOwner()->getDisplayName(),
+      'owner' => (($owner = $entity->getOwner()) && $owner instanceof UserInterface)
+        ? $owner->getDisplayName()
+        : $this->t('N/A'),
     ];
     $row['data'] = $row['data'] + parent::buildRow($entity);
 

core/modules/workspaces/tests/src/Functional/WorkspaceTest.php

@@ -299,6 +299,16 @@ public function testWorkspaceList() {
     // 'Live' is no longer the active workspace, so it's 'Switch to Live'
     // operation should be visible now.
     $assert_session->linkExists('Switch to Live');
+
+    // Delete any of the workspace owners and visit workspaces listing.
+    $this->drupalLogin($this->editor2);
+    user_cancel([], $this->editor1->id(), 'user_cancel_reassign');
+    $user = \Drupal::service('entity_type.manager')->getStorage('user')->load($this->editor1->id());
+    $user->delete();
+    $this->drupalGet('/admin/config/workflow/workspaces');
+    $this->assertSession()->pageTextContains('Summer event');
+    $summer_event_workspace_row = $page->find('css', 'table tbody tr:nth-of-type(3)');
+    $this->assertEquals('N/A', $summer_event_workspace_row->find('css', 'td:nth-of-type(2)')->getText());
   }
 
   /**