SingleAsPublisher hangs on subscribe(Subscriber) call

[Andrey Radchenko]

The subscribe(Subscriber s) method calls s.onSubscribe(...), which in turn calls request(n) and goes into infinite loop waiting for wrapped single to complete. But actual Single has not been subscribed to yet and therefore infinite loop will never end.

    @Override
    public void subscribe(Subscriber<? super T> s) {
        SingleAsPublisherSubscriber<T> parent = new SingleAsPublisherSubscriber<T>(s);
        s.onSubscribe(parent); // apparently, this goes into infinite loop and never returns

        single.subscribe(parent);
    }

[David Karnok]

Fixed via #156