Update src/Type/Definition/QueryPlan.php

Co-authored-by: Benedikt Franke <[email protected]>

Author: simPod

src/Type/Definition/QueryPlan.php

@@ -258,6 +258,7 @@ private function mergeFields(Type $parentType, Type $type, array $fields, array
         if ($this->groupImplementorFields && $parentType instanceof AbstractType && ! $type instanceof AbstractType) {
             $name = $type->name;
             assert(\is_string($name));
+
             $implementors[$name] = [
                 'type' => $type,
                 'fields' => $this->arrayMergeDeep(