diff --git a/src/Executor/Executor.php b/src/Executor/Executor.php
index fac9553..655c6fc 100644
--- a/src/Executor/Executor.php
+++ b/src/Executor/Executor.php
@@ -311,7 +311,10 @@ class Executor
                 return null;
             })
             ->then(function ($data) {
-                return new ExecutionResult((array) $data, $this->exeContext->errors);
+                if ($data === null){
+                    $data = (array) $data;
+                }
+                return new ExecutionResult($data, $this->exeContext->errors);
             });
     }
 
diff --git a/tests/Executor/NonNullTest.php b/tests/Executor/NonNullTest.php
index 1519f78..70b88c3 100644
--- a/tests/Executor/NonNullTest.php
+++ b/tests/Executor/NonNullTest.php
@@ -732,7 +732,6 @@ class NonNullTest extends \PHPUnit_Framework_TestCase
         ';
 
         $expected = [
-            'data' => null,
             'errors' => [
                 FormattedError::create($this->nonNullSyncError->getMessage(), [new SourceLocation(2, 17)])
             ]
@@ -750,7 +749,6 @@ class NonNullTest extends \PHPUnit_Framework_TestCase
         $ast = Parser::parse($doc);
 
         $expected = [
-            'data' => null,
             'errors' => [
                 FormattedError::create($this->nonNullPromiseError->getMessage(), [new SourceLocation(2, 17)]),
             ]
@@ -789,7 +787,6 @@ class NonNullTest extends \PHPUnit_Framework_TestCase
         $ast = Parser::parse($doc);
 
         $expected = [
-            'data' => null,
             'errors' => [
                 [
                     'debugMessage' => 'Cannot return null for non-nullable field DataType.nonNullPromise.',