public void PopulateStartingContextParameters_CalledWithStartingParameters()
        {
            Graph graph = new Graph();
            GraphContextParameter startingParameter = new GraphContextParameter {
                type = GraphContextParameterType.Int, key = "Key"
            };

            graph.AddStartingContextParameter(startingParameter);

            IGraphContext mockContext = Substitute.For <IGraphContext>();

            IGraphContextFactory stubFactory = Substitute.For <IGraphContextFactory>();

            stubFactory.MakeContext().Returns(mockContext);
            GraphContextFactoryLocator.Provide(stubFactory);

            graph.Start();

            mockContext.Received().PopulateStartingContextParameters(Arg.Is <IList <GraphContextParameter> >(list => list.Contains(startingParameter)));
        }