public void Element_ChangeOfElementPropertiesAfterAddingToCommandTree_ThrowsException() { RootCommand cmd = MPOptions.GetRoot(); Option opt = new Option("mike", "t1", false); Argument arg=new Argument("arg"); cmd.Add(opt).Add(arg); AssertHelper.Throws<InvalidOperationException>(() => opt.WithStaticValidator("foo","bar")); AssertHelper.Throws<InvalidOperationException>(() => arg.WithNoValidator()); }