* true when removing a connection from the pool; otherwise a racing caller might get it from the
   * pool when it shouldn't. Symmetrically, this must always be checked before returning a
   * connection from the pool.
   *
   * Once true this is always true. Guarded by this.
   */
  var noNewExchanges = false

  /**

  duration: Long,
  unit: TimeUnit,
): Int {
  check(duration >= 0L) { "$name < 0" }
  val millis = unit.toMillis(duration)
  require(millis <= Integer.MAX_VALUE) { "$name too large" }
  require(millis != 0L || duration <= 0L) { "$name too small" }
  return millis.toInt()
}

internal fun checkDuration(
  name: String,
  duration: Duration,
): Int {
  check(!duration.isNegative()) { "$name < 0" }

      if (ia.hasNext()) {
        add(ia.next())
      }
      if (ib.hasNext()) {
        add(ib.next())
      }
    }
  }
}

// TODO check read only options for creating lists
public fun <T> List<T>.readOnly() = this.toList()

// TODO check read only options for creating lists

    assertThat(verifier.verify("\u2121.com", session)).isFalse()
    assertThat(verifier.verify("℡.com", session)).isFalse()

    // These should ideally be false, but we know that hostname is usually already checked by us
    assertThat(verifier.verify("\u212A.com", session)).isFalse()
    // Kelvin character below
    assertThat(verifier.verify("K.com", session)).isFalse()
  }

  @Test fun specialKInCert() {

 * `java.net.URL` it's possible to create an awkward URL like `http:/` with scheme and path but no
 * hostname. Building APIs that consume such malformed values is difficult!
 *
 * This class has a modern API. It avoids punitive checked exceptions: [toHttpUrl] throws
 * [IllegalArgumentException] on invalid input or [toHttpUrlOrNull] returns null if the input is an
 * invalid URL. You can even be explicit about whether each component has been encoded already.
 *

    fun Response.hasVaryAll(): Boolean = "*" in headers.varyFields()

    /**
     * Returns the names of the request headers that need to be checked for equality when caching.
     */
    private fun Headers.varyFields(): Set<String> {
      var result: MutableSet<String>? = null
      for (i in 0 until size) {

Works with OkHttp
=================

Here’s some libraries that work nicely with OkHttp.

 * [Chucker](https://github.com/ChuckerTeam/chucker): An in-app HTTP inspector for Android OkHttp clients.
 * [Coil](https://github.com/coil-kt/coil): An image loading library for Android backed by Kotlin Coroutines.
 * [Communicator](https://github.com/Taig/Communicator): An OkHttp wrapper for Scala built with Android in mind.

    need them to handle redirects.


## Version 2.7.1

_2016-01-01_

 *  Fix: Don't do a health check on newly-created connections. This is
    unnecessary work that could put the client in an inconsistent state if the
    health check fails.


## Version 2.7.0

_2015-12-13_

 *  **Rewritten connection management.** Previously OkHttp's connection pool

            // We've exhausted our current label. Either there are more labels to compare, in which
            // case we expect a dot as the next character. Otherwise, we've checked all our labels.
            if (currentLabelIndex == labels.size - 1) {
              break
            } else {
              currentLabelIndex++
              currentLabelByteIndex = -1

        HTTP_TEMP_REDIRECT,
        -> {
          // These codes can only be cached with the right response headers.
          // http://tools.ietf.org/html/rfc7234#section-3
          // s-maxage is not checked because OkHttp is a private cache that should ignore s-maxage.
          if (response.header("Expires") == null &&
            response.cacheControl.maxAgeSeconds == -1 &&
            !response.cacheControl.isPublic &&