not limited to compiled object code, generated documentation,
      and conversions to other media types.

      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).

      not limited to compiled object code, generated documentation,
      and conversions to other media types.

      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).

      not limited to compiled object code, generated documentation,
      and conversions to other media types.

      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).

      not limited to compiled object code, generated documentation,
      and conversions to other media types.

      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).

      not limited to compiled object code, generated documentation,
      and conversions to other media types.

      "Work" shall mean the work of authorship, whether in Source or
      Object form, made available under the License, as indicated by a
      copyright notice that is included in or attached to the work
      (an example is provided in the Appendix below).

  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited
  // capacity is made available exclusively to this priority level.
  // Required.
  // +unionDiscriminator
  optional string type = 1;

  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited
  // capacity is made available exclusively to this priority level.
  // Required.
  // +unionDiscriminator
  optional string type = 1;

   * proxy server can issue an auth challenge and then close the connection.
   *
   * @return the next plan to attempt, or null if no further attempt should be made either because
   *     we've successfully connected or because no further attempts should be made.
   */
  @Throws(IOException::class)
  internal fun connectTunnel(): ConnectResult {
    val nextTunnelRequest =
      createTunnel()

  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited
  // capacity is made available exclusively to this priority level.
  // Required.
  // +unionDiscriminator
  optional string type = 1;

  // (and thus are never queued) and do not detract from the
  // capacity made available to other priority levels.  A value of
  // `"Limited"` means that (a) requests of this priority level
  // _are_ subject to limits and (b) some of the server's limited
  // capacity is made available exclusively to this priority level.
  // Required.
  // +unionDiscriminator
  optional string type = 1;