public void SerializeToXml_Empty() { var emptyGraph = new BidirectionalGraph <Person, Edge <Person> >(); SerializeAndRead( writer => emptyGraph.SerializeToXml( writer, person => person.Id, emptyGraph.GetEdgeIdentity(), GraphNodeName, VertexNodeName, EdgeNodeName, ""), content => { StringAssert.AreEqualIgnoringCase( $"{XmlHeader}{Environment.NewLine}<{GraphNodeName} />", content); }); }