public void Get_aggregated_post_have_not_effect_over_own_post_collection()
        {
            Charly.AddPost(new Post("aPost"));

            Marco.AggregatePosts.Should().HaveCount(1);
            Marco.Posts.Should().BeNullOrEmpty();
        }
        public void An_user_can_view_an_aggregate_list_of_all_subscriptions()
        {
            var marcoPost       = CreatePostInExplicitTime("Marco Post", 0);
            var firstCharlyPost = CreatePostInExplicitTime("First Charly Post", 500);
            var seconCharlyPost = CreatePostInExplicitTime("Second Charly Post", 1000);

            Marco.AddPost(marcoPost);
            Charly.AddPost(firstCharlyPost);
            Charly.AddPost(seconCharlyPost);

            Marco.AggregatePosts.ToArray().ShouldBeEquivalentTo(new [] { seconCharlyPost, firstCharlyPost, marcoPost });
            Marco.AggregatePosts.Should().BeInAscendingOrder(p => p.SecondsSinceCreation);
        }