public void ItSucceedsWhenItIsLowerBound()
        {
            ValidationRule <int> sut = GetSut(2, "a");

            sut.InRange(2, 4);
        }
        public void ItThrowsWhenValueIsToBig()
        {
            ValidationRule <int> sut = GetSut(4, "a");

            Assert.Throws <ArgumentOutOfRangeException>(() => sut.InRange(2, 3));
        }