diff --git a/Test/Integration/UniqueExecutorTest.php b/Test/Integration/UniqueExecutorTest.php
index f59321c..ec85c23 100644
--- a/Test/Integration/UniqueExecutorTest.php
+++ b/Test/Integration/UniqueExecutorTest.php
@@ -4,6 +4,7 @@
 
 use GraphQL\Executor\Promise\Adapter\SyncPromiseAdapter;
 use GraphQL\Language\AST\DocumentNode;
+use GraphQL\Language\AST\NodeList;
 use GraphQL\Type\Schema;
 use Graycore\GraphQlIntrospectionCache\Executor\ReferenceExecutor;
 use Magento\TestFramework\ObjectManager;
@@ -17,8 +18,9 @@ public function testThatCreatedExecutorsAreUnique()
 
         $promiseAdapter = $om->create(SyncPromiseAdapter::class);
         $schema = $om->create(Schema::class, ['config' => []]);
+        /** @var DocumentNode */
         $documentNode = $om->create(DocumentNode::class, ['vars' => []]);
-        $documentNode->definitions = [];
+        $documentNode->definitions = new NodeList([]);
 
         $first = ReferenceExecutor::create(
             $promiseAdapter,