public void DistanceBetweenTwoEdges_DelanceyBeckwith_ChannelThornlands()
        {
            var graph = new DirectedGraph(new[]
                                      {
                                          PointMother.DelanceySt, PointMother.ThornlandsRd, PointMother.BeckwithSt,
                                          PointMother.ChannelSt
                                      });
            var delanceyBeckwith = graph.GetEdge(new[] {PointMother.DelanceySt, PointMother.BeckwithSt});
            var channelThornlands = graph.GetEdge(new[] {PointMother.ChannelSt, PointMother.ThornlandsRd});

            var result = graph.DistanceBetweenTwoEdges(delanceyBeckwith, channelThornlands);
            Assert.AreEqual(4.0, result, 0.1);
        }