public void service_undoes_are_in_the_correct_order()
{
var p1 = new Person(null, false);
var p2 = new Person(null, false);
var p3 = new Person(null, false);
ChangeTrackingService svc = new ChangeTrackingService();
PersonCollection list = new PersonCollection(svc);
list.Add(p1);
list.Add(p2);
list.Add(p3);
list.Move(p2, 0);
list.Remove(p1);
svc.Undo();
Assert.AreEqual <int>(3, list.Count);
Assert.IsTrue(list.Contains(p1));
svc.Undo();
Assert.AreEqual <int>(1, list.IndexOf(p2));
svc.Undo();
Assert.AreEqual <int>(2, list.Count);
Assert.IsFalse(list.Contains(p3));
svc.Undo();
Assert.AreEqual <int>(1, list.Count);
Assert.IsFalse(list.Contains(p2));
svc.Undo();
Assert.AreEqual <int>(0, list.Count);
Assert.IsFalse(list.Contains(p1));
}