public void MondaiResultsThatAreReturnedFromGetItemsMethodDependOnDifficultyProperty()
        {
            var t0 = new DateTime(2013, 10, 2, 0, 0, 0); // UTC
            var t1 = t0 + TimeSpan.FromDays(2d);
            EPuzzleTime.Now = t1;
            var userInfo = new EPuzzleUserInfo();

            userInfo.Difficulty = Difficulty.Hard;

            Assert.AreEqual(Difficulty.Hard, userInfo.Difficulty);
            var mondaiResult0 = new MondaiResult("id50", t0, TimeSpan.FromSeconds(8d), Difficulty.Normal);
            var mondaiResult1 = new MondaiResult("id50", t1, TimeSpan.FromSeconds(8d), Difficulty.Hard);
            userInfo.MondaiResults.Add(mondaiResult0);
            userInfo.MondaiResults.Add(mondaiResult1);

            CollectionAssert.AreEqual(new [] { mondaiResult1, }, userInfo.MondaiResults.GetItems("id50"));

            var mondaiResult2 = userInfo.CreateMondaiResult("id50", t1, TimeSpan.FromSeconds(8d));
            Assert.AreEqual(Difficulty.Hard, mondaiResult2.Difficulty);
        }