public async Task ProcessOutboxMessages_WhenNoMessages_WaitsAccordingToBackoffStrategy() { _outboxStorage.When(o => o.Retrieve(_busDisposalCancellationTokenSource.Token, TopMessagesToRetrieve)).Do( c => { _busDisposalCancellationTokenSource.Cancel(); }); await _processor.Run(); await _backoffStrategy.Received().WaitNoMessageAsync(_busDisposalCancellationTokenSource.Token); }