Ask<object> will not throw exception when the response is Status.Failure

[ondravondra]

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Version Information Version of Akka.NET? 1.5.15

Describe the bug Ask

This is caused by the order of case statements in FutureActorRef<T>.TellInternal:

            switch (message)
            {
                case ISystemMessage msg:
                    handled = _result.TrySetException(new InvalidOperationException($"system message of type '{msg.GetType().Name}' is invalid for {nameof(FutureActorRef<T>)}"));
                    break;
                case T t:
                    handled = _result.TrySetResult(t);
                    break;
                case null:
                    handled = _result.TrySetResult(default);
                    break;
                case Status.Failure f:
                    handled = _result.TrySetException(f.Cause
                        ?? new TaskCanceledException("Task cancelled by actor via Failure message."));
                    break;

when T is object and message is Status.Failure the case T t: is executed instead of case Status.Failure f:.

[ondravondra]

This behaviour can be fixed by reordering the case labels, e.g.:

        {
            switch (reply)
            {
                case T wtv:
                    return wtv;
                case null:
                    return default;
                case Status.Failure fail:
                    throw fail.Cause;
                default:
                    throw new ArgumentException();
            }
        }

        private T GetResult2<T>(object reply)
        {
            switch (reply)
            {
                case Status.Failure fail:
                    throw fail.Cause;
                case T wtv:
                    return wtv;
                case null:
                    return default;
                default:
                    throw new ArgumentException();
            }
        }
        ```
The first method returns the Failure as object but the second method rethrows the exception.

[Aaronontheweb]

Nice catch! Yes, we should apply your fix and just re-do the case labels here. If you'd like to send in a small PR with a reproduction spec we'd be happy to merge it. We can write something ourselves too - but totally up to you.

[ondravondra]

reproduction spec we'd be happy to merge it. We can write something ourselves too - but totally up to you.

I am afraid I won't be able to write a PR with tests soon, I am really busy at work, sorry. Thanks for accepting the bug report tho, fixing it will allow us to simplify our company code.