public void testGetKeyMatchesString() {
    for (StandardSystemProperty property : StandardSystemProperty.values()) {
      String fieldName = property.name();
      String expected = Ascii.toLowerCase(fieldName).replaceAll("_", ".");
      assertEquals(expected, property.key());
    }
  }

  public void testGetValue() {
    for (StandardSystemProperty property : StandardSystemProperty.values()) {

  /**
   * Returns an {@link Escaper} instance that escapes strings so they can be safely included in <a
   * href="https://url.spec.whatwg.org/#syntax-url-path-segment">URL path segments</a>. The returned
   * escaper escapes all non-ASCII characters, even though <a
   * href="https://url.spec.whatwg.org/#url-code-points">many of these are accepted in modern
   * URLs</a>. (<a href="https://url.spec.whatwg.org/#path-state">If the escaper were to leave these

 */
@GwtCompatible
@NullUnmarked
public class CharsetsTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // Non-UTF-8 Charset
  public void testUsAscii() {
    assertEquals(Charset.forName("US-ASCII"), Charsets.US_ASCII);
  }

  @J2ktIncompatible
  @GwtIncompatible // Non-UTF-8 Charset
  public void testIso88591() {
    assertEquals(Charset.forName("ISO-8859-1"), Charsets.ISO_8859_1);
  }

        final byte[] derived = new byte[16];
        gen.generateBytes(derived, 0, 16);
        return derived;
    }

    /**
     * @param string
     * @return null terminated ASCII bytes
     */
    private static byte[] toCBytes(final String string) {
        final byte[] data = new byte[string.length() + 1];

                if (ntlm == null) {
                    return;
                }
            } else {
                final String auth = new String(Base64.decode(msg.substring(6)), "US-ASCII");
                int index = auth.indexOf(':');
                String user = index != -1 ? auth.substring(0, index) : auth;
                final String password = index != -1 ? auth.substring(index + 1) : "";

`secrets.compare_digest()` needs to take `bytes` or a `str` that only contains ASCII characters (the ones in English), this means it wouldn't work with characters like `á`, as in `Sebastián`.

To handle that, we first convert the `username` and `password` to `bytes` encoding them with UTF-8.

func hasNUL(s string) bool {
	return strings.Contains(s, "\x00")
}

// isASCII reports whether the input is an ASCII C-style string.
func isASCII(s string) bool {
	for _, c := range s {
		if c >= 0x80 || c == 0x00 {
			return false
		}
	}
	return true
}

// toASCII converts the input to an ASCII C-style string.
// This is a best effort conversion, so invalid characters are dropped.
func toASCII(s string) string {

    val headers =
      Headers
        .Builder()
        .add("WWW-Authenticate: Basic realm=\"protected area\", charset=\"US-ASCII\"")
        .build()
    val expectedAuthParams = mutableMapOf<String?, String>()
    expectedAuthParams["realm"] = "protected area"
    expectedAuthParams["charset"] = "US-ASCII"
    assertThat(headers.parseChallenges("WWW-Authenticate"))
      .isEqualTo(listOf(Challenge("Basic", expectedAuthParams)))
  }

        final int start = bufferIndex;

        pathConsumed = readInt2(buffer, bufferIndex);
        bufferIndex += 2;
        /* Samba 2.2.8a will reply with Unicode paths even though
         * ASCII is negotiated so we must use flags2 (probably
         * should anyway).
         */
        if ((flags2 & FLAGS2_UNICODE) != 0) {
            pathConsumed /= 2;
        }

 *  Fix: Don't crash when URLs have IPv4-mapped IPv6 addresses.
 *  Fix: Don't crash when building `HandshakeCertificates` on Android API 28.
 *  Fix: Permit multipart file names to contain non-ASCII characters.
 *  New: API to get MockWebServer's dispatcher.
 *  New: API to access headers as `java.time.Instant`.
 *  New: Fail fast if a `SSLSocketFactory` is used as a `SocketFactory`.