network.addEdge(N1, N1, E11);
    network.addEdge(N1, N1, E11_A);
    assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11, E11_A);
  }

  private static class NetworkForTest<N, E> extends AbstractNetwork<N, E> {
    private final Network<N, E> network;

    NetworkForTest(Network<N, E> network) {
      this.network = network;
    }

  var responder: (Request) -> Unit = {
    it.callback.onAnswer(listOf(), 0)
  }

  data class Request(
    val network: Network?,
    val domain: String,
    val nsType: Int,
    val flags: Int,
    val callback: DnsResolver.Callback<List<InetAddress>>,
  )

  @Implementation
  fun query(
    network: Network?,
    domain: String,
    nsType: Int,
    flags: Int,
    executor: Executor,

  /**
   * Returns a view of {@code network} with the direction (if any) of every edge reversed. All other
   * properties remain intact, and further updates to {@code network} will be reflected in the view.
   */
  public static <N, E> Network<N, E> transpose(Network<N, E> network) {
    if (!network.isDirected()) {
      return network; // the transpose of an undirected network is an identical network
    }

  /**
   * Returns a view of {@code network} with the direction (if any) of every edge reversed. All other
   * properties remain intact, and further updates to {@code network} will be reflected in the view.
   */
  public static <N, E> Network<N, E> transpose(Network<N, E> network) {
    if (!network.isDirected()) {
      return network; // the transpose of an undirected network is an identical network
    }

    private List<NetworkInterfaceInfo> interfaces;

    /**
     * Create query network interface info response
     */
    public QueryNetworkInterfaceInfoResponse() {
        this.interfaces = new ArrayList<>();
    }

    /**
     * Get the list of network interfaces
     *
     * @return list of network interface information
     */
    public List<NetworkInterfaceInfo> getInterfaces() {

    /** A duplicate name exists on the network */
    int NT_STATUS_DUPLICATE_NAME = 0xC00000bd;
    /** The specified network name is no longer available */
    int NT_STATUS_NETWORK_NAME_DELETED = 0xC00000c9;
    /** Network access is denied */
    int NT_STATUS_NETWORK_ACCESS_DENIED = 0xC00000ca;
    /** The network resource type is not correct */
    int NT_STATUS_BAD_DEVICE_TYPE = 0xC00000cb;

/**
 * A concrete interceptor chain that carries the entire interceptor chain: all application
 * interceptors, the OkHttp core, all network interceptors, and finally the network caller.
 *
 * If the chain is for an application interceptor then [exchange] must be null. Otherwise it is for
 * a network interceptor and [exchange] must be non-null.
 */
class RealInterceptorChain(
  internal val call: RealCall,

     */
    public enum ErrorCode {
        // Network errors
        CONNECTION_FAILED("Network connection failed", ErrorCategory.NETWORK, true), CONNECTION_TIMEOUT("Connection timed out",
                ErrorCategory.NETWORK, true), CONNECTION_RESET("Connection reset by peer", ErrorCategory.NETWORK,
                        true), HOST_NOT_FOUND("Host not found", ErrorCategory.NETWORK, false),

        // Authentication errors

  }

  static void assertStronglyEquivalent(Network<?, ?> networkA, Network<?, ?> networkB) {
    // Properties not covered by equals()
    assertThat(networkA.allowsParallelEdges()).isEqualTo(networkB.allowsParallelEdges());
    assertThat(networkA.allowsSelfLoops()).isEqualTo(networkB.allowsSelfLoops());
    assertThat(networkA.nodeOrder()).isEqualTo(networkB.nodeOrder());
    assertThat(networkA.edgeOrder()).isEqualTo(networkB.edgeOrder());

  }

  @Test
  fun networkInterceptorsRewriteRequestToServer() {
    rewriteRequestToServer(true)
  }

  private fun rewriteRequestToServer(network: Boolean) {
    server.enqueue(MockResponse())
    addInterceptor(network) { chain: Interceptor.Chain ->
      val originalRequest = chain.request()
      chain.proceed(
        originalRequest
          .newBuilder()