* overflow and return null.
   */
  @Test fun overflowEncodingOversizedLabel() {
    val a1000 = "a".repeat(1000)
    val a1000MaxCodePoint = a1000 + "\udbff\udfff"
    testEncodeDecode(
      a1000MaxCodePoint,
      "xn--$a1000-nc89312g",
    )
    assertNull(
      Punycode.encode(a1000MaxCodePoint.repeat(2)),
    )
  }

  @Test fun invalidPunycode() {
    assertNull(Punycode.decode("xn--ls8h="))
  }

 * limitations under the License.
 */
package okhttp3.internal.ws

import assertk.assertThat
import assertk.assertions.isEqualTo
import java.util.Random
import kotlin.test.assertFailsWith
import okhttp3.TestUtil.repeat
import okhttp3.internal.format
import okhttp3.internal.ws.WebSocketProtocol.OPCODE_BINARY
import okhttp3.internal.ws.WebSocketProtocol.OPCODE_TEXT
import okhttp3.internal.ws.WebSocketProtocol.PAYLOAD_BYTE_MAX

package okhttp3

/**
 * Provides **policy** and **persistence** for HTTP cookies.
 *
 * As policy, implementations of this interface are responsible for selecting which cookies to
 * accept and which to reject. A reasonable policy is to reject all cookies, though that may
 * interfere with session-based authentication schemes that require cookies.
 *
 * As persistence, implementations of this interface must also provide storage of cookies. Simple

    if (!commaPrefixed && (commaSuffixed || exhausted())) {
      result.add(
        Challenge(
          schemeName,
          Collections.singletonMap<String, String>(null, peek + "=".repeat(eqCount)),
        ),
      )
      peek = null
      continue
    }

    // It's a series of parameter names and values.
    val parameters = mutableMapOf<String?, String>()

import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.internal.SuppressSignatureCheck
import okhttp3.internal.platform.Platform

/**
 * Example of using a hardware key to perform client auth.
 * Prefer recent JDK builds, and results are temperamental to slight environment changes.
 * Different instructions and configuration may be required for other hardware devices.
 *
 * Using a yubikey device as a SSL key store.

 * Prefer to alternate IP addresses from different address families, (IPv6 / IPv4), starting with IPv6.
 * Don't start a new attempt until 250 ms after the most recent attempt was started.
 * Keep whichever TCP connection succeeds first and cancel all the others.
 * Race TCP only. Only attempt a TLS handshake on the winning TCP connection.

 * Connection pooling reduces request latency (if HTTP/2 isn’t available).
 * Transparent GZIP shrinks download sizes.
 * Response caching avoids the network completely for repeat requests.

OkHttp perseveres when the network is troublesome: it will silently recover from common connection
problems. If your service has multiple IP addresses, OkHttp will attempt alternate addresses if the

import okhttp3.Request;
import okhttp3.Response;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;

/**
 * Fetches HTML from a requested URL, follows the links, and repeats.
 */
public final class Crawler {
  private final OkHttpClient client;
  private final Set<HttpUrl> fetchedUrls = Collections.synchronizedSet(new LinkedHashSet<>());

      // OkHttp does not reject invalid Punycode.
      "xn--a",
      "xn--a.ß",
      "xn--a.xn--zca",
      "xn--a-yoc",
      // OkHttp doesn't reject U+FFFD encoded in Punycode.
      "xn--zn7c.com",
      // OkHttp doesn't reject a U+200D. https://www.rfc-editor.org/rfc/rfc5892.html#appendix-A.2
      "xn--1ug.example",

  @JvmStatic
  fun headerEntries(vararg elements: String?): List<Header> {
    return List(elements.size / 2) { Header(elements[it * 2]!!, elements[it * 2 + 1]!!) }
  }

  @JvmStatic
  fun repeat(
    c: Char,
    count: Int,
  ): String {
    val array = CharArray(count)
    Arrays.fill(array, c)
    return String(array)
  }

  /**