generate id method for exec-next

Author: rmosolgo

lib/graphql/schema/member/has_fields.rb

@@ -150,10 +150,14 @@ def field_class(new_field_class = nil)
 
         def global_id_field(field_name, **kwargs)
           type = self
-          field field_name, "ID", **kwargs, null: false
+          field field_name, "ID", **kwargs, null: false, resolve_each: true
           define_method(field_name) do
             context.schema.id_from_object(object, type, context)
           end
+
+          define_singleton_method(field_name) do |object, context|
+            context.schema.id_from_object(object, type, context)
+          end
         end
 
         # @param new_has_no_fields [Boolean] Call with `true` to make this Object type ignore the requirement to have any defined fields.