* ### Duplex APIs
   *
   * With regular request bodies it is not legal to write bytes to the sink passed to
   * [RequestBody.writeTo] after that method returns. For duplex requests bodies that condition is
   * lifted. Such writes occur on an application-provided thread and may occur concurrently with
   * reads of the [ResponseBody]. For duplex request bodies, [writeTo] should return

    @Throws(IOException::class)
    override fun writeTo(sink: BufferedSink) {
      val forwardingSink =
        object : ForwardingSink(sink) {
          private var totalBytesWritten: Long = 0
          private var completed = false

          override fun write(
            source: Buffer,
            byteCount: Long,
          ) {
            super.write(source, byteCount)
            totalBytesWritten += byteCount

            requestBody.writeTo(bufferedRequestBody)
          } else {
            // Write the request body if the "Expect: 100-continue" expectation was met.
            val bufferedRequestBody = exchange.createRequestBody(request, false).buffer()
            requestBody.writeTo(bufferedRequestBody)
            bufferedRequestBody.close()
          }
        } else {

) : RequestBody() {
  override fun contentType() = delegate.contentType()

  // We don't know the compressed length in advance!
  override fun contentLength() = -1L

  override fun writeTo(sink: BufferedSink) {
    GzipSink(sink).buffer().use(delegate::writeTo)
  }

  override fun isOneShot() = delegate.isOneShot()

 *
 * Unlike [okhttp3.ResponseBody], this interface is designed to be implemented by writers and not
 * called by readers.
 */
public interface MockResponseBody {
  /** The length of this response in bytes, or -1 if unknown. */
  public val contentLength: Long

  @Throws(IOException::class)
  public fun writeTo(sink: BufferedSink)

    @Override
    public long contentLength() throws IOException {
      return delegate.contentLength();
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
      BufferedSink bufferedSink = Okio.buffer(sink(sink));
      delegate.writeTo(bufferedSink);
      bufferedSink.flush();
    }

    public Sink sink(Sink sink) {
      return new ForwardingSink(sink) {

      )

    call.execute().use { response ->
      assertThat(response.body.string()).isEqualTo("abc")
      val requestBodyOut = requestBody.takeSink()
      assertFailsWith<IOException> {
        SlowRequestBody.writeTo(requestBodyOut)
      }
      assertFailsWith<IOException> {
        requestBodyOut.close()
      }
    }

    // Confirm that the connection pool was not corrupted by making another call.

   * versions.
   */
  public byte[] toByteArray() {
    ByteBuffer buffer = ByteBuffer.allocate(BYTES).order(ByteOrder.LITTLE_ENDIAN);
    xStats.writeTo(buffer);
    yStats.writeTo(buffer);
    buffer.putDouble(sumOfProductsOfDeltas);
    return buffer.array();
  }

  /**
   * Creates a {@link PairedStats} instance from the given byte representation which was obtained by

      override fun writeTo(sink: BufferedSink) {
        sink.writeUtf8("<el")
        sink.flush()
        throw IOException("failed to stream the XML")
      }
    }

    class ValidRequestBody : RequestBody() {
      override fun contentType(): MediaType = "application/xml".toMediaType()

      override fun writeTo(sink: BufferedSink) {
        sink.writeUtf8("<element/>")

	for _, fb := range full {
		buf.Write(fb)
	}
	buf.Write(frag)
	return buf.String(), err
}

// WriteTo implements io.WriterTo.
// This may make multiple calls to the [Reader.Read] method of the underlying [Reader].
// If the underlying reader supports the [Reader.WriteTo] method,
// this calls the underlying [Reader.WriteTo] without buffering.
func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
	b.lastByte = -1