public void Skin_AddCluster_AddsCluster()
{
// given:
var s = new Skin("");
var c = new Cluster("");
// require:
Assert.AreEqual(0, s.GetSrcObjectCount());
Assert.AreEqual(0, s.GetDstObjectCount());
Assert.AreEqual(0, s.GetClusterCount());
Assert.AreEqual(0, c.GetSrcObjectCount());
Assert.AreEqual(0, c.GetDstObjectCount());
// when:
s.AddCluster(c);
// then:
Assert.AreEqual(1, s.GetSrcObjectCount());
Assert.AreSame(c, s.GetSrcObject(0));
Assert.AreEqual(0, s.GetDstObjectCount());
Assert.AreEqual(1, s.GetClusterCount());
Assert.AreSame(c, s.GetCluster(0));
Assert.AreEqual(0, c.GetSrcObjectCount());
Assert.AreEqual(1, c.GetDstObjectCount());
Assert.AreSame(s, c.GetDstObject(0));
}