public void UpdateRemainderWhenSetOnSameDate()
        {
            dataProvider.SetRemainder(1.01.of2009(), 10);
            dataProvider.SetRemainder(1.01.of2009(), 20);

            persistentStorageMock.Verify(x => x.Set(dataContainer), Times.Exactly(2));
            AreEqual(1, dataProvider.GetRemainders().Count);
            AreEqual(1.01.of2009(), dataProvider.GetRemainders()[0].Date);
            AreEqual(20, dataProvider.GetRemainders()[0].Amount);
        }
        public void RemaindersAreCopied()
        {
            dataProvider.SetRemainder(1.02.of2009(), 10);
            //

            var preprocessor = CreatePreprocessor();

            CollectionAssert.AreEquivalent(dataProvider.GetRemainders(), preprocessor.Remainders);
        }