private void OnFormatEdge(TEdge e)
 {
     if (FormatEdge != null)
     {
         GraphvizEdge ev = new GraphvizEdge();
         FormatEdge(this, new FormatEdgeEventArgs <TVertex, TEdge>(ev, e));
         Output.Write(" {0}", ev.ToDot());
     }
 }
        public void WriteEdge(Object sender, EdgeEventArgs args)
        {
            GraphvizWriterAlgorithm algo = (GraphvizWriterAlgorithm)sender;

            algo.Output.Write(m_Edge.ToDot());
        }
 public void ToDot([NotNull] GraphvizEdge edge, [NotNull] string expectedDot)
 {
     Assert.AreEqual(expectedDot, edge.ToDot());
     Assert.AreEqual(expectedDot, edge.ToString());
 }