public void WithTestSetup(
            Action
            <TestSetup, Func <IGraphStageWithMaterializedValue <Shape, object>, BaseBuilder.AssemblyBuilder>,
             Func <ISet <TestSetup.ITestEvent> > > spec)
        {
            var setup = new TestSetup(Sys);

            spec(setup, g => setup.Builder(g), setup.LastEvents);
        }