/** Used for tags and subidentifiers. */
  private fun writeVariableLengthLong(v: Long) {
    val sink = sink()
    val bitCount = 64 - java.lang.Long.numberOfLeadingZeros(v)
    val byteCount = (bitCount + 6) / 7
    for (shift in (byteCount - 1) * 7 downTo 0 step 7) {
      val lastBit = if (shift == 0) 0 else 0b1000_0000
      sink.writeByte(((v shr shift) and 0b0111_1111).toInt() or lastBit)
    }
  }

              private var totalBytesWritten: Long = 0
              private var completed = false

              override fun write(source: Buffer, byteCount: Long) {
                super.write(source, byteCount)
                totalBytesWritten += byteCount
                progressListener.update(totalBytesWritten, contentLength(), completed)
              }

              override fun close() {

        private var cacheRequestClosed = false

        @Throws(IOException::class)
        override fun read(
          sink: Buffer,
          byteCount: Long,
        ): Long {
          val bytesRead: Long
          try {
            bytesRead = source.read(sink, byteCount)
          } catch (e: IOException) {
            if (!cacheRequestClosed) {
              cacheRequestClosed = true

      source: Buffer,
      byteCount: Long,
    ) {
      val toRead = minOf(remainingByteCount, byteCount)
      if (toRead > 0L) {
        source.read(buffer, toRead)
      }
      val toSkip = byteCount - toRead
      if (toSkip > 0L) {
        source.skip(toSkip)
      }
      remainingByteCount -= toRead
      receivedByteCount += byteCount
    }

    val name: String = headers.name(0)
    val value: String = headers.value(0)
    val names: Set<String> = headers.names()
    val values: List<String> = headers.values("")
    val byteCount: Long = headers.byteCount()
    val builder: Headers.Builder = headers.newBuilder()
    val multimap: Map<String, List<String>> = headers.toMultimap()
  }

  @Test
  fun headersBuilder() {

    override fun read(
      sink: Buffer,
      byteCount: Long,
    ): Long {
      while (left == 0) {
        source.skip(padding.toLong())
        padding = 0
        if (flags and FLAG_END_HEADERS != 0) return -1L
        readContinuationHeader()
        // TODO: test case for empty continuation header?
      }

      val read = source.read(sink, minOf(byteCount, left.toLong()))
      if (read == -1L) return -1L

        .build()
    connection.start(sendConnectionPreface = false)
    val queues = taskRunner.activeQueues()
    assertThat(queues).hasSize(1)
  }

  private fun data(byteCount: Int): Buffer = Buffer().write(ByteArray(byteCount))

  private fun assertStreamData(
    expected: String?,
    source: Source?,
  ) {
    val actual = source!!.buffer().readUtf8()
    assertThat(actual).isEqualTo(expected)

   * approximate size of HTTP/2 headers before they are compressed with HPACK. This value is
   * intended to be used as a metric: smaller headers are more efficient to encode and transmit.
   */
  fun byteCount(): Long {
    // Each header name has 2 bytes of overhead for ': ' and every header value has 2 bytes of
    // overhead for '\r\n'.
    var result = (namesAndValues.size * 2).toLong()

            headerCount,
          )
          nextHeaderIndex += entriesToEvict
        }
        return entriesToEvict
      }

      /**
       * Read `byteCount` bytes of headers from the source stream. This implementation does not
       * propagate the never indexed flag of a header.
       */
      @Throws(IOException::class)
      fun readHeaders() {

                var bytesWritten: Long = 0
                while (bytesWritten < contentLength) {
                  val byteCount = Math.min(buffer.size.toLong(), contentLength - bytesWritten).toInt()
                  bytesWritten += byteCount.toLong()
                  sink.write(buffer, 0, byteCount)
                }
              }
            },
        ),
      )
    assertContent("", response)