dname := t.TempDir()
	fname := filepath.Join(dname, "foo.txt")
	err := os.WriteFile(fname, []byte("Bar"), 0644)
	check("WriteFile", err)
	defer os.Remove(fname)

	tr := &Transport{}
	tr.RegisterProtocol("file", NewFileTransport(Dir(dname)))
	c := &Client{Transport: tr}

	fooURLs := []string{"file:///foo.txt", "file://../foo.txt"}
	for _, urlstr := range fooURLs {
		res, err := c.Get(urlstr)

// request.
//
// The typical use case for NewFileTransport is to register the "file"
// protocol with a [Transport], as in:
//
//	t := &http.Transport{}
//	t.RegisterProtocol("file", http.NewFileTransport(http.Dir("/")))
//	c := &http.Client{Transport: t}
//	res, err := c.Get("file:///etc/passwd")
//	...
func NewFileTransport(fs FileSystem) RoundTripper {

// ErrSkipAltProtocol is a sentinel error value defined by Transport.RegisterProtocol.
var ErrSkipAltProtocol = errors.New("net/http: skip alternate protocol")

// RegisterProtocol registers a new protocol with scheme.
// The [Transport] will pass requests using the given scheme to rt.
// It is rt's responsibility to simulate HTTP request semantics.
//
// RegisterProtocol can be used by other packages to provide

// Test that we use the older backward compatible cancellation protocol
// when a RoundTripper is registered via RegisterProtocol.
func TestAltProtoCancellation(t *testing.T) {
	defer afterTest(t)
	tr := &Transport{}
	c := &Client{
		Transport: tr,
		Timeout:   time.Millisecond,
	}
	tr.RegisterProtocol("cancel", cancelProto{})
	_, err := c.Get("cancel://bar.com/path")
	if err == nil {

}

// registerHTTPSProtocol calls Transport.RegisterProtocol but
// converting panics into errors.
func http2registerHTTPSProtocol(t *Transport, rt http2noDialH2RoundTripper) (err error) {
	defer func() {
		if e := recover(); e != nil {
			err = fmt.Errorf("%v", e)
		}
	}()
	t.RegisterProtocol("https", rt)
	return nil
}

		{"(*Server).Shutdown", Method, 8},
		{"(*Transport).CancelRequest", Method, 1},
		{"(*Transport).Clone", Method, 13},
		{"(*Transport).CloseIdleConnections", Method, 0},
		{"(*Transport).RegisterProtocol", Method, 0},
		{"(*Transport).RoundTrip", Method, 0},
		{"(ConnState).String", Method, 3},
		{"(Dir).Open", Method, 0},
		{"(HandlerFunc).ServeHTTP", Method, 0},
		{"(Header).Add", Method, 0},

pkg net/http, method (*Server) ListenAndServeTLS(string, string) error
pkg net/http, method (*Server) Serve(net.Listener) error
pkg net/http, method (*Transport) CloseIdleConnections()
pkg net/http, method (*Transport) RegisterProtocol(string, RoundTripper)
pkg net/http, method (*Transport) RoundTrip(*Request) (*Response, error)
pkg net/http, method (Dir) Open(string) (File, error)
pkg net/http, method (HandlerFunc) ServeHTTP(ResponseWriter, *Request)