public void ShouldDecorateAnExistingComponent()
{
IContainer container = new SimpleContainer();
container.Add <IThing, ThingWithNoDependencies>();
container.Decorate <IThing, DecoratedThing>();
var thing = container.Resolve <IThing>();
Assert.That(thing, Is.InstanceOfType(typeof(DecoratedThing)));
Assert.That(thing.Dependency, Is.InstanceOfType(typeof(ThingWithNoDependencies)));
}