* @param arrays zero or more {@code byte} arrays
   * @return a single array containing all the values from the source arrays, in order
   */
  public static byte[] concat(byte[]... arrays) {
    int length = 0;
    for (byte[] array : arrays) {
      length += array.length;
    }
    byte[] result = new byte[length];
    int pos = 0;
    for (byte[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);

	return Map(c.ToTitle, s)
}

// ToValidUTF8 treats s as UTF-8-encoded bytes and returns a copy with each run of bytes
// representing invalid UTF-8 replaced with the bytes in replacement, which may be empty.
func ToValidUTF8(s, replacement []byte) []byte {
	b := make([]byte, 0, len(s)+len(replacement))
	invalid := false // previous byte was from an invalid UTF-8 sequence
	for i := 0; i < len(s); {

              0x13579bdf,
              null,
              "df9b5713"),
          new ExpectedHashCode(
              new byte[] {(byte) 0xcd, (byte) 0xab, (byte) 0x00, (byte) 0x00},
              0x0000abcd,
              null,
              "cdab0000"),
          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x00,

              0x13579bdf,
              null,
              "df9b5713"),
          new ExpectedHashCode(
              new byte[] {(byte) 0xcd, (byte) 0xab, (byte) 0x00, (byte) 0x00},
              0x0000abcd,
              null,
              "cdab0000"),
          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x00,

      actual += expected;
    }
    assertEquals(EXPECTED_FOUR_BYTE_ROUNDTRIPPABLE_COUNT, actual);
  }

  private static String newString(char... chars) {
    return new String(chars);
  }

  private static byte[] toByteArray(int... bytes) {
    byte[] realBytes = new byte[bytes.length];
    for (int i = 0; i < bytes.length; i++) {
      realBytes[i] = (byte) bytes[i];
    }
    return realBytes;
  }

                new byte[] {(byte) 2, (byte) 3, (byte) 4}))
        .isEqualTo(2);
    assertThat(
            Bytes.indexOf(
                new byte[] {(byte) 2, (byte) 2, (byte) 3, (byte) 4, (byte) 2, (byte) 3, (byte) 4},
                new byte[] {(byte) 2, (byte) 3, (byte) 4}))
        .isEqualTo(1);
    assertThat(
            Bytes.indexOf(
                new byte[] {(byte) 4, (byte) 3, (byte) 2},

}

// Bytes provides a byte slice that can be serialized.
type Bytes []byte

// UnmarshalMsg deserializes b from the provided byte slice and returns the
// remainder of bytes.
func (b *Bytes) UnmarshalMsg(bytes []byte) ([]byte, error) {
	if b == nil {
		return bytes, errors.New("Bytes: UnmarshalMsg on nil pointer")
	}
	if bytes, err := msgp.ReadNilBytes(bytes); err == nil {
		if *b != nil {
			PutByteBuffer(*b)

		{
			desc:       "Correct sha256, truncated",
			src:        bytes.NewReader([]byte("abcd-morethan-4-bytes")),
			size:       4,
			actualSize: 4,
			sha256hex:  "88d4266fd4e6338d13b845fcf289579d209c897823b9217da3e161936f031589",
			err:        ioutil.ErrOverread,
		},
		{
			desc:       "Correct MD5, nested",
			src:        mustReader(t, bytes.NewReader([]byte("abcd")), 4, "", "", 4),
			size:       4,
			actualSize: 4,

                new byte[] {(byte) 2, (byte) 3, (byte) 4}))
        .isEqualTo(2);
    assertThat(
            Bytes.indexOf(
                new byte[] {(byte) 2, (byte) 2, (byte) 3, (byte) 4, (byte) 2, (byte) 3, (byte) 4},
                new byte[] {(byte) 2, (byte) 3, (byte) 4}))
        .isEqualTo(1);
    assertThat(
            Bytes.indexOf(
                new byte[] {(byte) 4, (byte) 3, (byte) 2},

  }

  @Test fun `five byte integer`() {
    val bytes = "02058000000001".decodeHex()
    assertThat(Adapters.INTEGER_AS_LONG.fromDer(bytes)).isEqualTo(-549755813887L)
    assertThat(Adapters.INTEGER_AS_LONG.toDer(-549755813887L)).isEqualTo(bytes)
  }

  @Test fun `eight zeros`() {
    val bytes = "020200ff".decodeHex()
    assertThat(Adapters.INTEGER_AS_LONG.fromDer(bytes)).isEqualTo(255)