TestHasher hasher = new TestHasher(); // byte order insignificant here
    byte[] expected = {1, 2, 3, 4, 5, 6, 7, 8};
    hasher.putByte((byte) 1);
    hasher.putBytes(new byte[] {2, 3, 4, 5, 6});
    hasher.putByte((byte) 7);
    hasher.putBytes(new byte[] {});
    hasher.putBytes(new byte[] {8});
    hasher.assertBytes(expected);
  }

  public void testShort() {
    TestHasher hasher = new TestHasher();

    BigInteger result = randomPositiveBigInteger(numBits);
    return RANDOM_SOURCE.nextBoolean() ? result : result.negate();
  }

  /**
   * Chooses a number in (-2^numBits, 2^numBits) at random, with density concentrated in numbers of
   * lower magnitude.
   */
  static BigInteger randomBigInteger(int numBits) {
    while (true) {
      if (RANDOM_SOURCE.nextBoolean()) {

        return this;
      }

      @Override
      public Hasher putBytes(byte[] bytes) {
        for (Hasher hasher : hashers) {
          hasher.putBytes(bytes);
        }
        return this;
      }

      @Override
      public Hasher putBytes(byte[] bytes, int off, int len) {
        for (Hasher hasher : hashers) {
          hasher.putBytes(bytes, off, len);
        }
        return this;
      }

    Sink sink = new Sink(4); // byte order insignificant here
    byte[] expected = {1, 2, 3, 4, 5, 6, 7, 8};
    sink.putByte((byte) 1);
    sink.putBytes(new byte[] {2, 3, 4, 5, 6});
    sink.putByte((byte) 7);
    sink.putBytes(new byte[] {});
    sink.putBytes(new byte[] {8});
    HashCode unused = sink.hash();
    sink.assertInvariants(8);
    sink.assertBytes(expected);
  }

  public void testShort() {

    @Override
    public Hasher putByte(byte b) {
      stream.write(b);
      return this;
    }

    @Override
    public Hasher putBytes(byte[] bytes, int off, int len) {
      stream.write(bytes, off, len);
      return this;
    }

    @Override
    public Hasher putBytes(ByteBuffer bytes) {
      stream.write(bytes);
      return this;
    }

    @Override
    public HashCode hash() {

  public Hasher putByte(byte b) {
    update(b);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(byte[] bytes) {
    checkNotNull(bytes);
    update(bytes);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(byte[] bytes, int off, int len) {
    checkPositionIndexes(off, off + len, bytes.length);
    update(bytes, off, len);
    return this;
  }

   */
  HashCode hashLong(long input);

  /**
   * Shortcut for {@code newHasher().putBytes(input).hash()}. The implementation <i>might</i>
   * perform better than its longhand equivalent, but should not perform worse.
   */
  HashCode hashBytes(byte[] input);

  /**
   * Shortcut for {@code newHasher().putBytes(input, off, len).hash()}. The implementation

    process(bb);
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putBytes(byte[] bytes, int off, int len) {
    return putBytesInternal(ByteBuffer.wrap(bytes, off, len).order(ByteOrder.LITTLE_ENDIAN));
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putBytes(ByteBuffer readBuffer) {
    ByteOrder order = readBuffer.order();
    try {

    @Override
    public InputStream openStream() {
      return new In();
    }

    public void append(byte[] b) {
      byte[] newBytes = Arrays.copyOf(bytes, bytes.length + b.length);
      System.arraycopy(b, 0, newBytes, bytes.length, b.length);
      bytes = newBytes;
    }

    private class In extends InputStream {
      private int pos;

      @Override
      public int read() throws IOException {

  @Override
  public void write(int b) throws IOException {
    hasher.putByte((byte) b);
    out.write(b);
  }

  @Override
  public void write(byte[] bytes, int off, int len) throws IOException {
    hasher.putBytes(bytes, off, len);
    out.write(bytes, off, len);
  }

  /**
   * Returns the {@link HashCode} based on the data written to this stream. The result is