hashFunction.hashUnencodedChars("abc"),
            hashFunction.newHasher().putUnencodedChars("abc").hash(),
            hashFunction.newHasher().putUnencodedChars("ab").putUnencodedChars("c").hash(),
            hashFunction.newHasher().putUnencodedChars("a").putUnencodedChars("bc").hash(),
            hashFunction
                .newHasher()
                .putUnencodedChars("a")
                .putUnencodedChars("b")

    Hasher hasher = Hashing.hmacMd5(MD5_KEY).newHasher();

    assertEquals(
        "9753980fe94daa8ecaa82216519393a9",
        hasher.putString("The quick brown fox jumps over the lazy dog", UTF_8).hash().toString());
    assertThrows(IllegalStateException.class, () -> hasher.putInt(42));
  }

  public void testHashTwice() {
    Hasher hasher = Hashing.hmacMd5(MD5_KEY).newHasher();

    assertEquals(

            hashFunction.hashUnencodedChars("abc"),
            hashFunction.newHasher().putUnencodedChars("abc").hash(),
            hashFunction.newHasher().putUnencodedChars("ab").putUnencodedChars("c").hash(),
            hashFunction.newHasher().putUnencodedChars("a").putUnencodedChars("bc").hash(),
            hashFunction
                .newHasher()
                .putUnencodedChars("a")
                .putUnencodedChars("b")

   * and checks that their results are identical, no matter which newHasher version we used.
   */
  public void testExhaustive() {
    List<Hasher> hashers =
        ImmutableList.of(
            new StreamingVersion().newHasher(),
            new StreamingVersion().newHasher(52),
            new NonStreamingVersion().newHasher(),
            new NonStreamingVersion().newHasher(123));
    Random random = new Random(0);

    hasher = HASH_FN.newHasher();
    hasher
        .putChar((char) 0x0101)
        .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
        .putChar((char) 0x0101)
        .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());

   *
   * {@snippet :
   * HashFunction hf = Hashing.md5();
   * HashCode hc = hf.newHasher()
   *     .putLong(id)
   *     .putBoolean(isActive)
   *     .hash();
   * }
   */
  Hasher newHasher();

  /**
   * Begins a new hash code computation as {@link #newHasher()}, but provides a hint of the expected

   *
   * {@snippet :
   * HashFunction hf = Hashing.md5();
   * HashCode hc = hf.newHasher()
   *     .putLong(id)
   *     .putBoolean(isActive)
   *     .hash();
   * }
   */
  Hasher newHasher();

  /**
   * Begins a new hash code computation as {@link #newHasher()}, but provides a hint of the expected

    int res = 0;
    for (int i = 0; i < reps; i++) {
      res +=
          System.identityHashCode(
              hashFunctionEnum
                  .getHashFunction()
                  .newHasher()
                  .putString(strings[i & SAMPLE_MASK], UTF_8)
                  .hash());
    }
    return res;
  }

  @Benchmark
  int hashUtf8GetBytes(int reps) {
    int res = 0;

    buffer = new ByteArrayInputStream(testBytes);

    when(hashFunction.newHasher()).thenReturn(hasher);
  }

  public void testRead_putSingleByte() throws Exception {
    HashingInputStream in = new HashingInputStream(hashFunction, buffer);

    int b = in.read();
    assertEquals('y', b);

    verify(hasher).putByte((byte) 'y');
    verify(hashFunction).newHasher();
    verifyNoMoreInteractions(hashFunction, hasher);
  }