public void NotNull()
        {
            var t = new TransformerNullToSet(_value);

            Assert.Equal("NotNull", t.Transform("NotNull", 0, 0));
        }
        public void NullToSet()
        {
            var t = new TransformerNullToSet(_value);

            Assert.Equal(_value, t.Transform(null, 0, 0));
        }