func (r *testOneByteReadEOF) Read(p []byte) (n int, err error) {
	if r.eof {
		return 0, io.EOF
	}
	n = copy(p, r.data)
	r.eof = true
	return n, io.EOF
}

// Return pointer to testOneByteReadNoEOF{}
func newTestReaderNoEOF(data []byte) io.Reader {
	return &testOneByteReadNoEOF{false, data}
}

// testOneByteReadNoEOF - implements io.Reader which returns 1 byte and nil error, but
// returns io.EOF on the next Read().