.timeout with small value on Single does not emit error. RxJava 2.2.21

[truebden]

Recently I notices a problem when using Single.timeout with a value really small. So in the snippet bellow you will see 0 nanoseconds, but it also happens with 10 nanoseconds. So also values > 0.
The problem is, that in such a case, the error is no always emitted.

		for (int i = 0; i < 10000000; i++) {
			final int y = i;
			final CountDownLatch latch = new CountDownLatch(1);
			Single.never()
					.timeout(0, TimeUnit.NANOSECONDS, Schedulers.computation())
					.subscribe(v -> {}, e -> {
						System.out.println("timeout " + y);
						latch.countDown();
					});
			if (!latch.await(1, TimeUnit.SECONDS)) {
				throw new IllegalStateException("Timeout was not happening!");
			}
		}

The workaround so far for me is to use a Single.timer instead.

		for (int i = 0; i < 10000000; i++) {
			final int y = i;
			final CountDownLatch latch = new CountDownLatch(1);
			Single.amb(Arrays.asList(Single.never(), Single.timer(0, TimeUnit.NANOSECONDS, Schedulers.computation()).doOnSuccess(l -> {
				throw new TimeoutException();
			})))
					.subscribe(v -> {}, e -> {
						System.out.println("timeout " + y);
						latch.countDown();
					});
			if (!latch.await(1, TimeUnit.SECONDS)) {
				throw new IllegalStateException("Timeout was not happening!");
			}
		}

The above snippets take like 2-3 minute to run in the success case. Most of the time the first one fails during that time, but sometimes also succeeds.
I tested it also with Observable, but could not notice the problematic behavior.

Do you have an idea where this comes from?

[akarnokd]

Very weird. Only Single.timeout fails this way, other components work. Also present in 3.x. I'll have to investigate further.

[akarnokd]

Found the bug. Note that 2.x is no longer maintained so the fix will only go to 3.1.x.

[truebden]

thank you a lot! The upgrade to version 3 should be done anyway.