val response = authenticator.onlyResponse()
    assertThat(response.request.url.toUrl().path).isEqualTo("/private")
    assertThat(response.challenges()).isEqualTo(listOf(Challenge("Basic", "protected area")))
  }

  @Test
  fun customTokenAuthenticator() {
    server.enqueue(
      MockResponse(
        code = 401,

        .addHeader("Last-Modified: " + formatDate(-1, TimeUnit.HOURS))
        .addHeader("Expires: " + formatDate(1, TimeUnit.HOURS))
        .code(responseCode)
        .body("ABCDE")
        .addHeader("WWW-Authenticate: challenge")
    when (responseCode) {
      HttpURLConnection.HTTP_PROXY_AUTH -> {
        builder.addHeader("Proxy-Authenticate: Basic realm=\"protected area\"")
      }

      HttpURLConnection.HTTP_UNAUTHORIZED -> {

          assertThat(response.code).isEqualTo(HttpURLConnection.HTTP_PROXY_AUTH)
          assertThat(response.request.url.host).isEqualTo("android.com")
          val challenges = response.challenges()
          assertThat(challenges[0].scheme).isEqualTo("OkHttp-Preemptive")
          response.request.newBuilder()
            .header("Proxy-Authorization", credential)
            .build()
        }