public async Task GroupByAccountGroupAsync_WhenCalled_ReturnsReadOnlyDictionaryWhereAllAccountCollectionsIsCalculated()
{
IAccountCollection sut = CreateSut();
sut.Add(CreateAccountCollection());
DateTime statusDate = DateTime.Now.AddDays(_random.Next(1, 365) * -1);
IReadOnlyDictionary <IAccountGroup, IAccountCollection> result = await(await sut.CalculateAsync(statusDate)).GroupByAccountGroupAsync();
Assert.That(result.Select(item => item.Value.StatusDate).All(value => value == statusDate.Date), Is.True);
}