public void removeAt() { var iter = ObjectMother.RANDOM.Next(1, 10); sut = new Section { Name = "s1" }; for(var i = 0; i < iter; i++) sut.append(ObjectMother.RandomAirplay("t" + i)); Assert.AreEqual(iter, sut.Airplays.Count()); visualizeSectionAndAirplays(); sut.removeAirplay(2); Assert.AreEqual(iter - 1, sut.Airplays.Count()); visualizeSectionAndAirplays(); }