public void to_uri()
        {
            Assert.Throws <ArgumentNullException>(() => ConvertExtensions.Uri(null, new object()));

            Assert.Null(Convert.To.Uri(null));
            var uri = new Uri("http://url.com");

            Assert.True(ReferenceEquals(Convert.To.Uri(uri), uri));
            Assert.Equal(uri, Convert.To.Uri("http://url.com"));
        }