req.RemoteAddr = "1.2.3.4:56789"
	closeCheck := new(checkCloser)
	logBuf := new(strings.Builder)
	outErr := errors.New("ModifyResponse error")
	rp := &ReverseProxy{
		Director: func(req *http.Request) {},
		Transport: &staticTransport{&http.Response{
			StatusCode: 200,
			Body:       closeCheck,
		}},
		ErrorLog: log.New(logBuf, "", 0),
		ModifyResponse: func(*http.Response) error {
			return outErr