public void PostThenTestForElement()
{
var p = new Port<int> ();
p.Post (33);
p.Post (44);
var res = p.TestForElement ();
Assert.IsNotNull (res, "#1");
Assert.IsNull (res.CausalityContext, "#1");
Assert.AreEqual (33, res.Item, "#2");
Assert.IsNotNull (res.Next, "#3");
Assert.AreEqual (p, res.Owner, "#4");
Assert.AreEqual (res.Next, res.Previous, "#5");
Assert.IsTrue (res is IPortElement<int>, "#6");
var typed = (IPortElement<int>)res;
Assert.AreEqual (33, typed.TypedItem, "#7");
}