diff --git a/src/testdir/test_vim9_class.vim b/src/testdir/test_vim9_class.vim
index bc8a8e1..4b6a730 100644
--- a/src/testdir/test_vim9_class.vim
+++ b/src/testdir/test_vim9_class.vim
@@ -203,6 +203,13 @@
   v9.CheckScriptSuccess(lines)
 enddef
 
+def Test_using_null_class()
+  var lines =<< trim END
+      @_ = null_class.member
+  END
+  v9.CheckDefExecAndScriptFailure(lines, ['E715:', 'E1363:'])
+enddef
+
 def Test_class_interface_wrong_end()
   var lines =<< trim END
       vim9script