public void TestGetAll()
        {
            DepartmentsService       service     = CreateService();
            IEnumerable <Department> departments = service.GetAll();

            // The service must always return a collection, even when empty.
            Assert.NotNull(departments);

            // The service must return two items according to test configuration.
            Assert.Equal(2, departments.Count());
        }
        public void TestGetAllEmpty()
        {
            // Parameter named to avoid confusion.
            DepartmentsService       service     = CreateService(empty: true);
            IEnumerable <Department> departments = service.GetAll();

            // The service must always return a collection, even when empty.
            Assert.NotNull(departments);

            // The service must return no items according to test configuration.
            Assert.Empty(departments);
        }