public void SectionRepository_CanStore()
        {
            var repo       = new SectionRepository();
            var section    = new Section("секция 1");
            var subsection = new Subsection("первый подраздел");

            section.Add(subsection);
            repo.Store(section); // without error
        }
        public void SectionRepository_CanRetrieve()
        {
            var repo        = new SectionRepository();
            var section     = new Section("секция 1");
            var subsection1 = new Subsection("первый подраздел");
            var subsection2 = new Subsection("второй подраздел");

            section.Add(subsection1, subsection2);
            repo.Store(section);

            var actual = repo.Retrieve(section.Id);

            Assert.AreEqual(section, actual);
        }