@CanIgnoreReturnValue
  @Override
  Hasher putByte(byte b);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(byte[] bytes);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(byte[] bytes, int off, int len);

  @CanIgnoreReturnValue
  @Override
  Hasher putBytes(ByteBuffer bytes);

  @CanIgnoreReturnValue
  @Override
  Hasher putShort(short s);

  @CanIgnoreReturnValue
  @Override

    byte[] bytes = {1, 2, 3, 4};
    out.write(255);
    out.write(bytes);
    out.write(bytes, 1, 2);
    verify(sink).putByte((byte) 255);
    verify(sink).putBytes(bytes);
    verify(sink).putBytes(bytes, 1, 2);
  }

  public void testSerialization() {
    assertSame(
        Funnels.byteArrayFunnel(), SerializableTester.reserialize(Funnels.byteArrayFunnel()));

  }

  @Benchmark
  int hasher(int reps) {
    HashFunction hashFunction = hashFunctionEnum.getHashFunction();
    int result = 37;
    for (int i = 0; i < reps; i++) {
      result ^= hashFunction.newHasher().putBytes(testBytes).hash().asBytes()[0];
    }
    return result;
  }

  @Benchmark
  int hashFunction(int reps) {
    HashFunction hashFunction = hashFunctionEnum.getHashFunction();
    int result = 37;

      }
    },
    HASH_FUNCTION_VIA_HASHER() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        return algorithm.getHashFunction().newHasher().putBytes(input).hash().asBytes();
      }
    };
    ;

    public abstract byte[] hash(Algorithm algorithm, byte[] input);
  }

  private enum Algorithm {
    MD5("MD5", Hashing.md5()),

        .putChar((char) 0x0100)
        .putChar((char) 0x0000)
        .putChar((char) 0x0000);
    assertEquals(hashCode, hasher.hash().asLong());

    hasher = HASH_FN.newHasher();
    hasher.putBytes(new byte[] {0x01, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00});
    assertEquals(hashCode, hasher.hash().asLong());

    hasher = HASH_FN.newHasher();
    hasher.putLong(0x0000000001000101L);

    assertEquals(
        String.format("expected: %08x, actual: %08x", expectedCrc, actualCrc),
        expectedCrc,
        actualCrc);
    int actualCrcHasher = Hashing.crc32c().newHasher().putBytes(data).hash().asInt();
    assertEquals(
        String.format("expected: %08x, actual: %08x", expectedCrc, actualCrc),
        expectedCrc,
        actualCrcHasher);
  }

    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() {