public void Compare_Should_SeeLeftStringEqualsRightString()
        {
            var left     = "aaa";
            var right    = "aaa";
            var comparer = new GradeLevelComparer();

            var result = comparer.Compare(left, right);

            result.ShouldEqual(0);
        }
        public void Compare_Should_SeeLeftIntGreaterThanRightString()
        {
            var left     = "123";
            var right    = "aaa";
            var comparer = new GradeLevelComparer();

            var result = comparer.Compare(left, right);

            result.ShouldBeGreaterThan(0);
        }
        public void Compare_Should_SeeLeftIntLessThanRightInt()
        {
            var left     = "2";
            var right    = "3";
            var comparer = new GradeLevelComparer();

            var result = comparer.Compare(left, right);

            result.ShouldBeLessThan(0);
        }