),
        )
      }
      frameHeader(
        streamId = streamId,
        length = 4,
        type = TYPE_WINDOW_UPDATE,
        flags = FLAG_NONE,
      )
      sink.writeInt(windowSizeIncrement.toInt())
      sink.flush()
    }
  }

  @Throws(IOException::class)
  fun frameHeader(
    streamId: Int,
    length: Int,
    type: Int,
    flags: Int,

    writer.frameHeader(0, newMaxFrameSize, Http2.TYPE_DATA, FLAG_NONE)
  }

  @Test fun streamIdHasReservedBit() {
    val writer = Http2Writer(Buffer(), true)
    assertFailsWith<IllegalArgumentException> {
      var streamId = 3
      streamId = streamId or (1L shl 31).toInt() // set reserved bit
      writer.frameHeader(streamId, Http2.INITIAL_MAX_FRAME_SIZE, Http2.TYPE_DATA, FLAG_NONE)