assertSame(CharMatcher.any(), CharMatcher.any().precomputed());
  }

  @GwtIncompatible // java.util.BitSet
  private static BitSet bitSet(String chars) {
    return bitSet(chars.toCharArray());
  }

  @GwtIncompatible // java.util.BitSet
  private static BitSet bitSet(char[] chars) {
    BitSet tmp = new BitSet();
    for (char c : chars) {
      tmp.set(c);
    }
    return tmp;
  }

   *
   * <p><b>Note:</b> consider representing the array as a {@link java.util.BitSet} instead,
   * replacing {@code Booleans.contains(array, true)} with {@code !bitSet.isEmpty()} and {@code
   * Booleans.contains(array, false)} with {@code bitSet.nextClearBit(0) == sizeOfBitSet}.
   *
   * @param array an array of {@code boolean} values, possibly empty

   *
   * <p><b>Note:</b> consider representing the array as a {@link java.util.BitSet} instead,
   * replacing {@code Booleans.contains(array, true)} with {@code !bitSet.isEmpty()} and {@code
   * Booleans.contains(array, false)} with {@code bitSet.nextClearBit(0) == sizeOfBitSet}.
   *
   * @param array an array of {@code boolean} values, possibly empty

    assertSame(CharMatcher.any(), CharMatcher.any().precomputed());
  }

  @GwtIncompatible // java.util.BitSet
  private static BitSet bitSet(String chars) {
    return bitSet(chars.toCharArray());
  }

  @GwtIncompatible // java.util.BitSet
  private static BitSet bitSet(char[] chars) {
    BitSet tmp = new BitSet();
    for (char c : chars) {
      tmp.set(c);
    }
    return tmp;
  }

    assertTrue(ArbitraryInstances.get(BitSet.class).isEmpty());
    assertTrue(ArbitraryInstances.get(TreeSet.class).isEmpty());
    assertTrue(ArbitraryInstances.get(TreeMap.class).isEmpty());
    assertFreshInstanceReturned(
        LinkedList.class,
        Deque.class,
        Queue.class,
        PriorityQueue.class,
        BitSet.class,
        TreeSet.class,
        TreeMap.class);
  }

    assertTrue(ArbitraryInstances.get(BitSet.class).isEmpty());
    assertTrue(ArbitraryInstances.get(TreeSet.class).isEmpty());
    assertTrue(ArbitraryInstances.get(TreeMap.class).isEmpty());
    assertFreshInstanceReturned(
        LinkedList.class,
        Deque.class,
        Queue.class,
        PriorityQueue.class,
        BitSet.class,
        TreeSet.class,
        TreeMap.class);
  }

    int keyBits = 32;
    int hashBits = function.bits();

    // output loop tests input bit
    for (int i = 0; i < keyBits; i++) {
      int same = 0x0; // bitset for output bits with same values
      int diff = 0x0; // bitset for output bits with different values
      int count = 0;
      // originally was 2 * Math.log(...), making it try more times to avoid flakiness issues

          bytes[15], bytes[14], bytes[13], bytes[12], bytes[11], bytes[10], bytes[9], bytes[8]);
    }
  };

  /**
   * Models a lock-free array of bits.
   *
   * <p>We use this instead of java.util.BitSet because we need access to the array of longs and we
   * need compare-and-swap.
   */
  static final class LockFreeBitArray {
    private static final int LONG_ADDRESSABLE_BITS = 6;
    final AtomicLongArray data;

     * {@code null} is returned.
     */
    private static <K, V> Entry<K, V> @Nullable [] lastEntryForEachKey(
        Entry<K, V>[] entries, int size) {
      Set<K> seen = new HashSet<>();
      BitSet dups = new BitSet(); // slots that are overridden by a later duplicate key
      for (int i = size - 1; i >= 0; i--) {
        if (!seen.add(entries[i].getKey())) {
          dups.set(i);
        }
      }

    // Serial form:
    // 1 signed byte for the strategy
    // 1 unsigned byte for the number of hash functions
    // 1 big endian int, the number of longs in our bitset
    // N big endian longs of our bitset
    DataOutputStream dout = new DataOutputStream(out);
    dout.writeByte(SignedBytes.checkedCast(strategy.ordinal()));