*     argument. These are matched by position - the first {@code %s} gets {@code
   *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
   *     square braces. Unmatched placeholders will be left as-is.
   * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
   *     are converted to strings using {@link String#valueOf(Object)}.

```

Do NOT translate with (German) - notice the dash:

```
## Typhinweise und –annotationen { #type-hints-and-annotations }
```

- Do not modify the hyphens in the content in headers inside of curly braces, which you shall not translate.

### German instructions, when to use and when not to use hyphens in words (written in first person, which is you).

   *     argument. These are matched by position - the first {@code %s} gets {@code
   *     errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in
   *     square braces. Unmatched placeholders will be left as-is.
   * @param errorMessageArgs the arguments to be substituted into the message template. Arguments
   *     are converted to strings using {@link String#valueOf(Object)}.

 */
internal fun String.toCanonicalHost(): String? {
  val host: String = this

  // If the input contains a :, it’s an IPv6 address.
  if (":" in host) {
    // If the input is encased in square braces "[...]", drop 'em.
    val inetAddressByteArray =
      (
        if (host.startsWith("[") && host.endsWith("]")) {
          decodeIpv6(host, 1, host.length - 1)
        } else {

        assertEquals("OPTIONS", Method.OPTIONS.toString());
        assertEquals("TRACE", Method.TRACE.toString());
        assertEquals("CONNECT", Method.CONNECT.toString());
    }

    // --- URL with special characters tests ---

    @Test
    public void test_UrlWithSpaces() {
        // ## Arrange ##
        // URLs with spaces should be accepted (HttpURLConnection is lenient)

    @Test
    public void test_UrlWithSpecialCharacters_ThroughRealConnectPath() throws Exception {
        // ## Arrange ##
        // URLs with special characters (spaces, curly braces, pipes) must be accepted
        // by the real connect() path using new URL()
        String[] specialUrls = { "http://localhost:9200/{index}/_search", "http://example.com/path?q=a|b",

 *   <li>192.0.2.1
 *   <li>192.0.2.1:80
 *   <li>[2001:db8::1] - {@link #getHost()} omits brackets
 *   <li>[2001:db8::1]:80 - {@link #getHost()} omits brackets
 *   <li>2001:db8::1 - Use {@link #requireBracketsForIPv6()} to prohibit this
 * </ul>
 *
 * <p>Note that this is not an exhaustive list, because these methods are only concerned with
 * brackets, colons, and port numbers. Full validation of the host field (if desired) is the

<h2 id="restrictions">Implementation Restrictions for Programs Containing Data Races</h2>

<p>
The preceding section gave a formal definition of data-race-free program execution.
This section informally describes the semantics that implementations must provide
for programs that do contain races.
</p>

<p>
Any implementation can, upon detecting a data race,
report the race and halt execution of the program.

    opcode = b0 and B0_MASK_OPCODE
    isFinalFrame = b0 and B0_FLAG_FIN != 0
    isControlFrame = b0 and OPCODE_FLAG_CONTROL != 0

    // Control frames must be final frames (cannot contain continuations).
    if (isControlFrame && !isFinalFrame) {
      throw ProtocolException("Control frames must be final.")
    }

    val reservedFlag1 = b0 and B0_FLAG_RSV1 != 0
    when (opcode) {
      OPCODE_TEXT, OPCODE_BINARY -> {

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