public void Build_a_chart_4_satellites_at_depth_1_and_2() { var chart = new AstronomicalChart(new AstronomicalObject("com")); var a = new AstronomicalObject("a"); chart.Root.AddSatellite(a); var a2 = new AstronomicalObject("a"); a.AddSatellite(a2); var b = new AstronomicalObject("b"); chart.Root.AddSatellite(b); var b2 = new AstronomicalObject("b2"); a.AddSatellite(b2); var calculator = new ChecksumCalculator(); var checksum = calculator.GetChecksum(chart); Assert.AreEqual(6, checksum); }