NullReferenceException upon dispose subscription about trill

[jmajoor]

TestCase:

The test case has a thread as a data feed and waits until at least one invocation occurs in the subscription. After this it will dispose the subscription (the input thread will keep running until canceled).

Expected behavior: The test to run to completion.

Actual behavior: A null reference exception due to the disposed currentBatch state and the non disposed observable.

    [TestMethod, TestCategory("Gated")]
    public async Task DisposeTest1()
    {
        var cancelTokenSource = new CancellationTokenSource();
        var inputSubject = new Subject<int>();
        var lastSeenSubscription = 0;
        var observableInput = inputSubject.AsObservable();

        var inputTask = new Task(() =>
        {
            var n = 0;
            while (!cancelTokenSource.Token.IsCancellationRequested)
            {
                inputSubject.OnNext(++n);
                Thread.Sleep(10);
            }
            inputSubject.OnCompleted();
        });

        var semaphore = new SemaphoreSlim(0, 1);
        var subscription = observableInput.ToAtemporalStreamable(TimelinePolicy.Sequence(1)).Count().ToStreamEventObservable().Where(c => c.IsData).Subscribe(c =>
        {
            Interlocked.Exchange(ref lastSeenSubscription, (int)c.Payload);
            if (semaphore.CurrentCount == 0) semaphore.Release();
        });
        // Start the input feed.
        inputTask.Start();
        // Wait until we have at least one output data event.
        await semaphore.WaitAsync();
        // Dispose the subscription.
        subscription.Dispose();
        // Keep the input feed going, before cancel. This should behave properly if the subscription is disposed of properly.
        await Task.Delay(200);
        cancelTokenSource.Cancel();
        await inputTask;
        // Make sure we really got an output data event.
        Assert.IsTrue(lastSeenSubscription > 0);
    }

[cybertyche]

Good call on all accounts, @jmajoor. Checking in a fix shortly.

[cybertyche]

Issue should be fixed now! Thank you for your help!