public void RegisterFactoryAsSingleton()
{
var builder = new ContainerBuilder();
builder.RegisterFactory(c => new InjectingContainer(c)).As<InjectingContainer>().SingleInstance();
var container = builder.Build();
var obj = container.Resolve<InjectingContainer>();
Assert.Same(container, obj.Container);
Assert.Same(obj, container.Resolve<InjectingContainer>());
}