Issue #2944215 by jeqq, alexpott: Aliases generated by...

Issue #2944215 by jeqq, alexpott: Aliases generated by PathItem::generateSampleValue() should start with a slash

core/modules/path/src/Plugin/Field/FieldType/PathItem.php

@@ -89,7 +89,7 @@ public function postSave($update) {
    */
   public static function generateSampleValue(FieldDefinitionInterface $field_definition) {
     $random = new Random();
-    $values['alias'] = str_replace(' ', '-', strtolower($random->sentences(3)));
+    $values['alias'] = '/' . str_replace(' ', '-', strtolower($random->sentences(3)));
     return $values;
   }
 

core/modules/path/tests/src/Kernel/PathItemTest.php

@@ -189,6 +189,18 @@ public function testPathItem() {
     // Change the alias for the second node to a different one and try again.
     $second_node->get('path')->alias = '/foobar';
     $this->assertFalse($node->get('path')->equals($second_node->get('path')));
+
+    // Test the generateSampleValue() method.
+    $node = Node::create([
+      'title' => $this->randomString(),
+      'type' => 'foo',
+      'path' => ['alias' => '/foo'],
+    ]);
+    $node->save();
+    $path_field = $node->get('path');
+    $path_field->generateSampleItems();
+    $node->save();
+    $this->assertStringStartsWith('/', $node->get('path')->alias);
   }
 
 }