private val requestedUris = mutableListOf<URI>()
  private val failures = mutableListOf<String>()

  override fun select(uri: URI): List<Proxy> {
    requestedUris.add(uri)
    return proxies
  }

  fun assertRequests(vararg expectedUris: URI?) {
    assertThat(requestedUris).containsExactly(*expectedUris)
    requestedUris.clear()
  }

  override fun connectFailed(
    uri: URI,
    sa: SocketAddress,
    ioe: IOException,

  @Throws(UnknownHostException::class)
  override fun lookup(hostname: String): List<InetAddress> {
    requestedHosts.add(hostname)
    return hostAddresses[hostname] ?: throw UnknownHostException()
  }

  fun assertRequests(vararg expectedHosts: String?) {
    assertThat(requestedHosts).containsExactly(*expectedHosts)
    requestedHosts.clear()
  }

  /** Allocates and returns `count` fake IPv4 addresses like [255.0.0.100, 255.0.0.101].  */