public void Ohne_Weckzeit_keine_Restzeit()
        {
            var sut = new Wecker(null);

            var result = new TimeSpan(0);
            sut.Restzeit += _ => result = _;

            sut.Zeitzeichen(new DateTime(2013, 1, 24, 9, 58, 0));

            Assert.AreEqual(new TimeSpan(0), result);
        }
        public void Restzeit_berechnen()
        {
            var sut = new Wecker(null);

            var result = new TimeSpan(0);
            sut.Restzeit += _ => result = _;

            sut.Starten(new Tuple<DateTime, TimeSpan>(new DateTime(2013,1,24,10,0,0), new TimeSpan(0)));
            sut.Zeitzeichen(new DateTime(2013,1,24,9,58,0));

            Assert.AreEqual(new TimeSpan(0,2,0), result);
        }