[TEST] Update Akka.TestKit to run asynchronous internally.

[Arkatufus]

Right now, Akka.TestKit relies on a BlockingQueue internally inside TestState making all test to run async over sync, In order to support full asynchronous test operations, we will need to replace this with something that supports async operation better. The main goal of this spec is to invert all operations into sync over async instead.

The biggest problem right now is the InternalTryReceiveOne() method in the TestKitBase class, it blocks as it waits for a message to get queued into the BlockingQueue<T>. This method gets called by virtually all akka test function that waits for one message or another. This method needs to be converted into an async method.

Options:

• Wrap InternalTryReceiveOne() inside an async function that uses Task.Run() to spin it in another thread.

private async Task<(bool, MessageEnvelope)> InternalTryReceiveOneAsync(TimeSpan? max, CancellationToken cancellationToken, bool shouldLog)
{
    return await Task.Run(() =>
    {
        var result = InternalTryReceiveOne(out var envelope, max, cancellationToken, shouldLog);
        return (result, envelope);
    }, cancellationToken);
}

• Replace the internal BlockingQueue<T> implementation with a custom System.Threading.Channels.Channel<T> that supports async read and write
• Replace the internal BlockingQueue<T> implementation with AsyncEx AsyncCollection or AsyncProducerConsumerQueue

[brah-mcdude]

Please let me know if you want me to help. I need this feature more than anyone.

[Arkatufus]

Will do, thanks for the offer.

[Arkatufus]

All the code are done but can't really be tested until all of the unit tests are converted to the new async code