} catch (ConcurrentModificationException expected) {
    }
  }

  /** Tests a failure caused by fix to childless uncle issue. */
  public void testIteratorRegressionChildlessUncle() {
    final ArrayList<Integer> initial = Lists.newArrayList(1, 15, 13, 8, 9, 10, 11, 14);
    MinMaxPriorityQueue<Integer> q = MinMaxPriorityQueue.create(initial);
    assertIntact(q);
    q.remove(9);

    } catch (ConcurrentModificationException expected) {
    }
  }

  /** Tests a failure caused by fix to childless uncle issue. */
  public void testIteratorRegressionChildlessUncle() {
    final ArrayList<Integer> initial = Lists.newArrayList(1, 15, 13, 8, 9, 10, 11, 14);
    MinMaxPriorityQueue<Integer> q = MinMaxPriorityQueue.create(initial);
    assertIntact(q);
    q.remove(9);