public async Task CreateBlob_CanceledDuringCreate() { var cts = new CancellationTokenSource(); var data = new byte[1024 * 1024]; Func <Task> f = async() => { while (true) { var blob = await _session.CreateBlobAsync(ct : cts.Token); await _session.BlobWriteAsync(blob, data, -1, ct : cts.Token); } }; var assertion = f.ShouldThrowAsync <OperationCanceledException>(); cts.CancelAfter(1); await assertion; }