internal fun connectFailed(
    client: OkHttpClient,
    failedRoute: Route,
    failure: IOException,
  ) {
    // Tell the proxy selector when we fail to connect on a fresh connection.
    if (failedRoute.proxy.type() != Proxy.Type.DIRECT) {
      val address = failedRoute.address
      address.proxySelector.connectFailed(
        address.url.toUri(),
        failedRoute.proxy.address(),

    // Check that a fresh connection was created, either immediately or after attempting reuse.
    // We know that a fresh connection was created if the server recorded a request with sequence
    // number 0. Since the client may have attempted to reuse the broken connection just before
    // creating a fresh connection, the server may have recorded 2 requests at this point. The order

    assertThat(client.connectionPool.connectionCount()).isEqualTo(2)
    assertThat(server.takeRequest().sequenceNumber)
      .isEqualTo(0) // Fresh connection.
    assertThat(server.takeRequest().sequenceNumber)
      .isEqualTo(0) // Fresh connection.
  }

  /**
   * Check we would use an existing connection to a later DNS result instead of connecting to the
   * first DNS result for the first time.

        .minFresh(3.seconds)
        .onlyIfCached()
        .noTransform()
        .immutable()
        .build()
    assertThat(cacheControl.toString()).isEqualTo(
      "no-cache, no-store, max-age=1, max-stale=2, min-fresh=3, only-if-cached, no-transform, immutable",
    )
    assertThat(cacheControl.noCache).isTrue()
    assertThat(cacheControl.noStore).isTrue()
    assertThat(cacheControl.maxAgeSeconds).isEqualTo(1)

          .headers(conditionalRequestHeaders.build())
          .build()
      return CacheStrategy(conditionalRequest, cacheResponse)
    }

    /**
     * Returns the number of milliseconds that the response was fresh for, starting from the served
     * date.
     */
    private fun computeFreshnessLifetime(): Long {
      val responseCaching = cacheResponse!!.cacheControl
      if (responseCaching.maxAgeSeconds != -1) {

          .url(server.url("/"))
          .build(),
      )
    val response1 = call1.execute()
    assertThat(response1.body.string()).isEqualTo("abc")
    response1.close()

    // Force a fresh connection for the next request.
    client.connectionPool.evictAll()

    // Confirm that a second request also succeeds. This should detect caching problems.
    server.enqueue(
      MockResponse.Builder()

        .build(),
    )
    assertThat(get(server.url("/")).body.string()).isEqualTo("A")
    val request =
      Request.Builder()
        .url(server.url("/"))
        .header("Cache-Control", "min-fresh=120")
        .build()
    val response = client.newCall(request).execute()
    assertThat(response.body.string()).isEqualTo("B")
  }

  @Test
  fun requestMaxStale() {
    server.enqueue(

        .onlyIfCached()
        .noTransform()
        .immutable()
        .build()
    assertThat(cacheControl.toString()).isEqualTo(
      "no-cache, no-store, max-age=1, max-stale=2, min-fresh=3, only-if-cached, " +
        "no-transform, immutable",
    )
    assertThat(cacheControl.noCache).isTrue()
    assertThat(cacheControl.noStore).isTrue()
    assertThat(cacheControl.maxAgeSeconds).isEqualTo(1)

        if (mustRevalidate) append("must-revalidate, ")
        if (maxStaleSeconds != -1) append("max-stale=").append(maxStaleSeconds).append(", ")
        if (minFreshSeconds != -1) append("min-fresh=").append(minFreshSeconds).append(", ")
        if (onlyIfCached) append("only-if-cached, ")
        if (noTransform) append("no-transform, ")
        if (immutable) append("immutable, ")
        if (isEmpty()) return ""

      assertThat(ioe.cause!!).isInstanceOf<EOFException>()
    }
  }

  // TODO GET preferred order - with tests to confirm this
  // 1. successful fresh cached GET response
  // 2. unsuccessful (404, 500) fresh cached GET response
  // 3. successful network response
  // 4. successful stale cached GET response
  // 5. unsuccessful response
  @Test
  fun usesCache() {