public async Task FullyReadsEmptyStream(int bufferSize, int maxBytesWritten)
            {
                InnerSource.SetLength(0);

                var result = await Source.CopyToAsync(Destination, bufferSize, maxBytesWritten, CancellationToken.None);

                Assert.Empty(Destination.ToArray());
                Assert.Equal(0, result.BytesWritten);
                Assert.Equal(0, Source.BytesRead);
                Assert.False(result.PartialRead);
            }