labelStart = dot + 1
  }

  return false
}

internal fun String.containsInvalidHostnameAsciiCodes(): Boolean {
  for (i in 0 until length) {
    val c = this[i]
    // The WHATWG Host parsing rules accepts some character codes which are invalid by
    // definition for OkHttp's host header checks (and the WHATWG Host syntax definition). Here
    // we rule out characters that would cause problems in host headers.

    response even if the server rejects your request body.
 *  Fix: Use literal IP addresses directly rather than passing them to `DnsOverHttps`.
 *  Fix: Embed Proguard rules to prevent warnings from tools like DexGuard and R8. These warnings
    were triggered by OkHttp’s feature detection for TLS packages like `org.conscrypt`,
    `org.bouncycastle`, and `org.openjsse`.

  }

  @Flaky
  @RetryingTest(5)
  fun missingClientAuthFailsForNeeds() {
    // Fails with 11.0.1 https://github.com/square/okhttp/issues/4598
    // StreamReset stream was reset: PROT...
    val client = buildClient(null, clientIntermediateCa.certificate)
    val socketFactory = buildServerSslSocketFactory()
    server.useHttps(socketFactory)
    server.requireClientAuth()

      val clientCertificates =
        HandshakeCertificates.Builder()
          .addPlatformTrustedCertificates()
          .addInsecureHost(server.hostName)
          .build()

      // Need fresh client to reset sslSocketFactoryOrNull
      client =
        OkHttpClient.Builder()
          .eventListenerFactory(
            clientTestRule.wrap(
              object : EventListener() {

    // Check that we do indeed have more than one route.
    assertThat(regularRoutes.size).isEqualTo(numberOfAddresses)
    // Add first regular route as failed.
    routeDatabase.failed(regularRoutes[0])
    // Reset selector
    routeSelector = newRouteSelector(address)

    // The first selection prioritizes the non-failed routes.
    val selection2 = routeSelector.next()
    assertThat(selection2.next()).isEqualTo(regularRoutes[1])

        .fastFallback(false)
        .apply {
          retryOnConnectionFailure = false
        }
        .build()

    executeSynchronously(request)
      .assertFailureMatches("stream was reset: REFUSED_STREAM")

    assertThat(client.routeDatabase.failedRoutes).isEmpty()
    assertThat(server1.requestCount).isEqualTo(1)
    assertThat(server2.requestCount).isEqualTo(0)

 */
@Timeout(30)
class FastFallbackTest {
  @RegisterExtension
  val clientTestRule = OkHttpClientTestRule()

  // Don't use JUnit 5 test rules for these; otherwise we can't bind them to a single local IP.
  private lateinit var localhostIpv4: InetAddress
  private lateinit var localhostIpv6: InetAddress
  private lateinit var serverIpv4: MockWebServer

      }
      sink.flush()
    }
  }

  /**
   * Send a connection-level ping to the peer. `ack` indicates this is a reply. The data in
   * `payload1` and `payload2` opaque binary, and there are no rules on the content.
   */
  @Throws(IOException::class)
  fun ping(
    ack: Boolean,
    payload1: Int,
    payload2: Int,
  ) {
    this.withLock {
      if (closed) throw IOException("closed")

    /** HTTP/2 only. */
    fun ackSettings()

    /**
     * Read a connection-level ping from the peer. `ack` indicates this is a reply. The data
     * in `payload1` and `payload2` opaque binary, and there are no rules on the content.
     */
    fun ping(
      ack: Boolean,
      payload1: Int,
      payload2: Int,
    )

    /**
     * The peer tells us to stop creating streams. It is safe to replay streams with

class HpackTest {
  private val bytesIn = Buffer()
  private var hpackReader: Hpack.Reader? = null
  private val bytesOut = Buffer()
  private var hpackWriter: Hpack.Writer? = null

  @BeforeEach
  fun reset() {
    hpackReader = newReader(bytesIn)
    hpackWriter = Hpack.Writer(4096, false, bytesOut)
  }

  /**
   * Variable-length quantity special cases strings which are longer than 127 bytes.  Values such as