public void ClearPropertyValidator_should_remove_property() { validator.RuleFor(x => x.Surname).Length(5, 10).WithMessage("foo"); var result = validator.Validate(new Person { Surname = "Matthew Leibowitz" }); result.Errors.Single().ErrorMessage.ShouldEqual("foo"); validator.ClearRules(x => x.Surname); result = validator.Validate(new Person { Surname = "Matthew Leibowitz" }); Assert.Equal(0, result.Errors.Count); }