): MockResponse.Builder {
    val response = builder.build()
    builder.onResponseEnd(ShutdownConnection)
    val headers = response.headers
    val fullBody = Buffer()
    response.body!!.writeTo(fullBody)
    val truncatedBody = Buffer()
    truncatedBody.write(fullBody, numBytesToKeep.toLong())
    builder.body(truncatedBody)
    builder.headers(headers)
    return builder
  }

pkg io, type Writer interface, Write([]uint8) (int, error)
pkg io, type WriterAt interface { WriteAt }
pkg io, type WriterAt interface, WriteAt([]uint8, int64) (int, error)
pkg io, type WriterTo interface { WriteTo }
pkg io, type WriterTo interface, WriteTo(Writer) (int64, error)
pkg io, var EOF error
pkg io, var ErrClosedPipe error
pkg io, var ErrShortBuffer error
pkg io, var ErrShortWrite error
pkg io, var ErrUnexpectedEOF error

pkg bufio, func ScanLines([]uint8, bool) (int, []uint8, error)
pkg bufio, func ScanRunes([]uint8, bool) (int, []uint8, error)
pkg bufio, func ScanWords([]uint8, bool) (int, []uint8, error)
pkg bufio, method (*Reader) WriteTo(io.Writer) (int64, error)
pkg bufio, method (*Scanner) Bytes() []uint8
pkg bufio, method (*Scanner) Err() error
pkg bufio, method (*Scanner) Scan() bool
pkg bufio, method (*Scanner) Split(SplitFunc)