public async Task TidyRecords_WhenAddingRecords_ShouldFillInGapsInBuketsIfNecessary()
        {
            var sut = new PerformanceStats(TimeSpan.FromMilliseconds(30), 3);

            await Task.Delay(150);

            var records = (Queue<PerformanceRecord>)sut.Records;

            sut.TidyRecords();

            var now = DateTime.Now;

            var last = records.Skip(2).First();
            var middle = records.Skip(1).First();
            var first = records.Skip(0).First();
            last.EndTime.Should().BeWithin(TimeSpan.FromMilliseconds(50)).After(now);
            last.EndTime.Should().BeWithin(TimeSpan.FromMilliseconds(50)).Before(now);

            var oneMS = TimeSpan.FromMilliseconds(1);
            last.StartTime.Should().BeWithin(oneMS).After(middle.EndTime);
            middle.StartTime.Should().BeWithin(oneMS).After(first.EndTime);
        }
        public async Task TidyRecords_WhenAddingRecords_ShouldNotOverflowMaxRecordCount()
        {
            var sut = new PerformanceStats(TimeSpan.FromMilliseconds(30), 3);

            await Task.Delay(150);

            var records = (Queue<PerformanceRecord>)sut.Records;

            sut.TidyRecords();

            records.Count.Should().Be(3);
        }