public void TestHasClass()
        {
            var elements = new HElement[] {
                new HElement("p", "First paragraph."),
                null,
                new HElement("p", new HAttribute("class", "selected"), "Second paragraph is selected.")
            };

            Assert.False(elements[0].HasClass(null));
            Assert.False(elements[0].HasClass("selected"));
            Assert.False(elements[1].HasClass("selected"));
            Assert.True(elements[2].HasClass("selected"));
            Assert.False(elements.HasClass(null));
            Assert.False(elements.HasClass("not-selected"));
            Assert.True(elements.HasClass("selected"));
        }