@NullUnmarked
enum HashFunctionEnum {
  ADLER32(adler32()),
  CRC32(crc32()),
  GOOD_FAST_HASH_32(goodFastHash(32)),
  GOOD_FAST_HASH_64(goodFastHash(64)),
  GOOD_FAST_HASH_128(goodFastHash(128)),
  GOOD_FAST_HASH_256(goodFastHash(256)),
  MD5(md5()),
  MURMUR3_128(murmur3_128()),
  MURMUR3_32(murmur3_32()),
  MURMUR3_32_FIXED(murmur3_32_fixed()),
  SHA1(sha1()),

@NullUnmarked
enum HashFunctionEnum {
  ADLER32(adler32()),
  CRC32(crc32()),
  GOOD_FAST_HASH_32(goodFastHash(32)),
  GOOD_FAST_HASH_64(goodFastHash(64)),
  GOOD_FAST_HASH_128(goodFastHash(128)),
  GOOD_FAST_HASH_256(goodFastHash(256)),
  MD5(md5()),
  MURMUR3_128(murmur3_128()),
  MURMUR3_32(murmur3_32()),
  MURMUR3_32_FIXED(murmur3_32_fixed()),
  SHA1(sha1()),

    HashTestUtils.checkNoFunnels(Hashing.goodFastHash(32));
    HashTestUtils.assertInvariants(Hashing.goodFastHash(32));
  }

  // goodFastHash(128) uses Murmur3_128. Use the same epsilon bounds.
  public void testGoodFastHash128() {
    HashTestUtils.check2BitAvalanche(Hashing.goodFastHash(128), 250, 0.20);
    HashTestUtils.checkAvalanche(Hashing.goodFastHash(128), 500, 0.17);

   * @return a hash function, described above, that produces hash codes of length {@code
   *     minimumBits} or greater
   */
  public static HashFunction goodFastHash(int minimumBits) {
    int bits = checkPositiveAndMakeMultipleOf32(minimumBits);

    if (bits == 32) {
      return Murmur3_32HashFunction.GOOD_FAST_HASH_32;
    }
    if (bits <= 128) {

  static final HashFunction MURMUR3_32_FIXED =
      new Murmur3_32HashFunction(0, /* supplementaryPlaneFix= */ true);

  // We can include the non-BMP fix here because Hashing.goodFastHash stresses that the hash is a
  // temporary-use one. Therefore it shouldn't be persisted.
  static final HashFunction GOOD_FAST_HASH_32 =
      new Murmur3_32HashFunction(GOOD_FAST_HASH_SEED, /* supplementaryPlaneFix= */ true);