Optimistic Concurrency in RavenDB

gistfile1.cs

[Subject("Raven Experiments")]
public class when_updating_same_object_in_separate_sessions : raven_persistence_context
{
    static Exception Exception;

    Establish context = () => StoreSingleObject(new MyClass {Text = "this one"});
    Because of = () => Exception = Catch.Exception(UpdateTwoObjectsInTwoSessions);
    It should_throw_concurrency_exception = () => Exception.ShouldBeOfType<ConcurrencyException>();

    static void UpdateTwoObjectsInTwoSessions()
    {
        using (var session = Store.OpenSession())
        {
            session.Advanced.UseOptimisticConcurrency = true;
            session
                .Query<MyClass>()
                .First()
                .Text = "still one";

            AtTheSameTimeInAnotherSession();

            session.SaveChanges();
        }
    }

    static void AtTheSameTimeInAnotherSession()
    {
        using (var anotherSession = Store.OpenSession())
        {
            anotherSession
                .Query<MyClass>()
                .First()
                .Text = "ha ha";
            anotherSession.SaveChanges();
        }
    }

    public class MyClass
    {
        public string Id { get; set; }
        public string Text;
    }
}