}
    }

    // Test that 0xFFFE and 0xFFFF are replaced with 0xFFFD
    assertEscaping(xmlEscaper, "\uFFFD", '\uFFFE');
    assertEscaping(xmlEscaper, "\uFFFD", '\uFFFF');

    assertEquals(
        "0xFFFE is forbidden and should be replaced during escaping",
        "[\uFFFD]",
        xmlEscaper.escape("[\ufffe]"));
    assertEquals(
        "0xFFFF is forbidden and should be replaced during escaping",

      <match value="0xfffa" type="string" offset="0"/> <!-- V1, L3, CRC -->
      <match value="0xfffb" type="string" offset="0"/> <!-- V1, L3      -->
      <match value="0xfffc" type="string" offset="0"/> <!-- V1, L2, CRC -->
      <match value="0xfffd" type="string" offset="0"/> <!-- V1, L2      -->
      <match value="0xffe3" type="string" offset="0"/> <!-- MP3 2.5 from pronom     -->

    frameLength = (b1 and B1_MASK_LENGTH).toLong()
    if (frameLength == PAYLOAD_SHORT.toLong()) {
      frameLength = (source.readShort() and 0xffff).toLong() // Value is unsigned.
    } else if (frameLength == PAYLOAD_LONG.toLong()) {
      frameLength = source.readLong()
      if (frameLength < 0L) {
        throw ProtocolException(

	SUBS	$0xffff0, R6, RSP                                // ERROR "illegal destination register"
	SUBS	$0x1000100010001000, R6, RSP                     // ERROR "illegal destination register"
	SUBS	$0x10001000100011, R6, RSP                       // ERROR "illegal destination register"
	SUBSW	$0xff, R6, RSP                                   // ERROR "illegal destination register"

    assertThat(converter.convert("0")).isEqualTo(0);
    assertThat(converter.convert("-1")).isEqualTo(-1);
    assertThat(converter.convert("0xff")).isEqualTo(255);
    assertThat(converter.convert("0xFF")).isEqualTo(255);
    assertThat(converter.convert("-0xFF")).isEqualTo(-255);
    assertThat(converter.convert("#0000FF")).isEqualTo(255);
    assertThat(converter.convert("0666")).isEqualTo(438);
  }

    for (int i = 0; i <= 0xff; i++) {
      assertThat(UnsignedBytes.toString((byte) i)).isEqualTo(Integer.toString(i));
    }
  }

  public void testToStringWithRadix() {
    // We can easily afford to test this exhaustively.
    for (int radix = Character.MIN_RADIX; radix <= Character.MAX_RADIX; radix++) {
      for (int i = 0; i <= 0xff; i++) {

        for (int i = 0; i < sz; i++) {
            char ch = str.charAt(i);
            // handle unicode
            if (ch > 0xfff) {
                out.append("\\u").append(hex(ch));
            } else if (ch > 0xff) {
                out.append("\\u0").append(hex(ch));
            } else if (ch > 0x7f) {
                out.append("\\u00").append(hex(ch));
            } else if (ch < 32) {

   *
   * @since 7.0
   */
  public static int fromBytes(byte b1, byte b2, byte b3, byte b4) {
    return b1 << 24 | (b2 & 0xFF) << 16 | (b3 & 0xFF) << 8 | (b4 & 0xFF);
  }

  private static final class IntConverter extends Converter<String, Integer>
      implements Serializable {
    static final Converter<String, Integer> INSTANCE = new IntConverter();

  @GwtIncompatible // Chars.fromByteArray
  public void testFromByteArray() {
    assertThat(Chars.fromByteArray(new byte[] {0x23, 0x45, (byte) 0xDC})).isEqualTo('\u2345');
    assertThat(Chars.fromByteArray(new byte[] {(byte) 0xFE, (byte) 0xDC})).isEqualTo('\uFEDC');
  }

  @GwtIncompatible // Chars.fromByteArray
  public void testFromByteArrayFails() {
    assertThrows(

	{" ", []rune{32}, false},
	{"ABC", []rune{65, 66, 67}, false},
	{"abc", []rune{97, 98, 99}, false},
	{"\u65e5\u672c\u8a9e", []rune{26085, 26412, 35486}, false},
	{"ab\x80c", []rune{97, 98, 0xFFFD, 99}, true},
	{"ab\xc0c", []rune{97, 98, 0xFFFD, 99}, true},
}

func TestRunes(t *testing.T) {
	for _, tt := range RunesTests {
		tin := []byte(tt.in)
		a := Runes(tin)
		if !slices.Equal(a, tt.out) {