assertFalse(keys.remove(key));
        assertFalse(keys.contains(key));
      }
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

  public void testValues_populated() {
    for (LoadingCache<Object, Object> cache : caches()) {
      Collection<Object> values = cache.asMap().values();
      List<Entry<Object, Object>> warmed = warmUp(cache);