@Test
public void testToFutureList() throws InterruptedException, ExecutionException {

    Observable<String> obs = Observable.just("one", "two", "three");
    Future<List<String>> f = toFuture(obs.toList());
    assertEquals("one", f.get().get(0));
    assertEquals("two", f.get().get(1));
    assertEquals("three", f.get().get(2));
}