}

  /**
   * Quickselects the top k elements from the 2k elements in the buffer. O(k) expected time, O(k log
   * k) worst case.
   */
  @SuppressWarnings("nullness") // TODO: b/316358623 - Remove after checker fix.
  private void trim() {
    int left = 0;
    int right = 2 * k - 1;

    int minThresholdPosition = 0;
    // The leftmost position at which the greatest of the k lower elements

    /*
     * If greatestOf() promised to be implemented as reverse().leastOf(), this
     * test would be enough. It doesn't... but we'll cheat and act like it does
     * anyway. There's a comment there to remind us to fix this if we change it.
     */
    List<Integer> list = Arrays.asList(3, 1, 3, 2, 4, 2, 4, 3);
    assertEquals(Arrays.asList(4, 4, 3, 3), numberOrdering.greatestOf(list, 4));
  }

    /*
     * If greatestOf() promised to be implemented as reverse().leastOf(), this
     * test would be enough. It doesn't... but we'll cheat and act like it does
     * anyway. There's a comment there to remind us to fix this if we change it.
     */
    List<Integer> list = Arrays.asList(3, 1, 3, 2, 4, 2, 4, 3);
    assertEquals(Arrays.asList(4, 4, 3, 3), numberOrdering.greatestOf(list, 4));
  }

    return fromEntries(comparator, sameComparator, entryArray, entryArray.length);
  }

  @SuppressWarnings("nullness") // TODO: b/316358623 - Remove after checker fix.
  private static <K, V> ImmutableSortedMap<K, V> fromEntries(
      final Comparator<? super K> comparator,
      boolean sameComparator,
      @Nullable Entry<K, V>[] entryArray,
      int size) {

    try {
      it.next();
      fail("No exception thrown when iterating a modified heap");
    } 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);

   *     order
   * @throws IllegalArgumentException if {@code k} is negative
   * @since 8.0
   */
  @SuppressWarnings("nullness") // TODO: b/316358623 - Remove after checker fix.
  public <E extends T> List<E> leastOf(Iterable<E> iterable, int k) {
    if (iterable instanceof Collection) {
      Collection<E> collection = (Collection<E>) iterable;
      if (collection.size() <= 2L * k) {

   * not actually very useful and will likely be deprecated in the future.
   */
  @SafeVarargs
  @GwtCompatible(serializable = true)
  @SuppressWarnings("nullness") // TODO: b/316358623 - Remove after checker fix.
  public static <E extends @Nullable Object> ArrayList<E> newArrayList(E... elements) {
    checkNotNull(elements); // for GWT
    // Avoid integer overflow when a large array is passed in

   * This method is not actually very useful and will likely be deprecated in the future.
   */
  @SuppressWarnings("nullness") // TODO: b/316358623 - Remove after checker fix.
  public static <E extends @Nullable Object> HashSet<E> newHashSet(E... elements) {
    HashSet<E> set = newHashSetWithExpectedSize(elements.length);
    Collections.addAll(set, elements);
    return set;
  }

  @Override
  /*
   * This suppression is here for two reasons:
   *
   * 1. b/192354773 in our checker affects toArray declarations.
   *
   * 2. `other[size] = null` is unsound. We could "fix" this by requiring callers to pass in an
   * array with a nullable element type. But probably they usually want an array with a non-nullable
   * type. That said, we could *accept* a `@Nullable T[]` (which, given that we treat arrays as

  @Override
  /*
   * This suppression is here for two reasons:
   *
   * 1. b/192354773 in our checker affects toArray declarations.
   *
   * 2. `other[size] = null` is unsound. We could "fix" this by requiring callers to pass in an
   * array with a nullable element type. But probably they usually want an array with a non-nullable
   * type. That said, we could *accept* a `@Nullable T[]` (which, given that we treat arrays as