return func(ts *httptest.Server) {
		ts.Config.ErrorLog = lg
	}
}

// newClientServerTest creates and starts an httptest.Server.
//
// The mode parameter selects the implementation to test:
// HTTP/1, HTTP/2, etc. Tests using newClientServerTest should use
// the 'run' function, which will start a subtests for each tested mode.
//

	"time"
)

func TestResponseControllerFlush(t *testing.T) { run(t, testResponseControllerFlush) }
func testResponseControllerFlush(t *testing.T, mode testMode) {
	continuec := make(chan struct{})
	cst := newClientServerTest(t, mode, HandlerFunc(func(w ResponseWriter, r *Request) {
		ctl := NewResponseController(w)
		w.Write([]byte("one"))
		if err := ctl.Flush(); err != nil {
			t.Errorf("ctl.Flush() = %v, want nil", err)
			return
		}

			}
			return b, nil
		}
		if err != nil {
			return b, err
		}
	}
}

func TestClient(t *testing.T) { run(t, testClient) }
func testClient(t *testing.T, mode testMode) {
	ts := newClientServerTest(t, mode, robotsTxtHandler).ts

	c := ts.Client()
	r, err := c.Get(ts.URL)
	var b []byte
	if err == nil {
		b, err = pedanticReadAll(r.Body)
		r.Body.Close()
	}
	if err != nil {
		t.Error(err)

func testHostHandlers(t *testing.T, mode testMode) {
	mux := NewServeMux()
	for _, h := range handlers {
		mux.Handle(h.pattern, stringHandler(h.msg))
	}
	ts := newClientServerTest(t, mode, mux).ts

	conn, err := net.Dial("tcp", ts.Listener.Addr().String())
	if err != nil {
		t.Fatal(err)
	}
	defer conn.Close()
	cc := httputil.NewClientConn(conn, nil)

					go io.Copy(targetConn, clientConn)
					go func() {
						io.Copy(clientConn, targetConn)
						targetConn.Close()
					}()
				}
			})
			ts := newClientServerTest(t, siteMode, h1).ts
			proxy := newClientServerTest(t, proxyMode, h2).ts

			pu, err := url.Parse(proxy.URL)
			if err != nil {
				t.Fatal(err)
			}

	{r: "bytes=100-1000", code: StatusRequestedRangeNotSatisfiable},
}

func TestServeFile(t *testing.T) { run(t, testServeFile) }
func testServeFile(t *testing.T, mode testMode) {
	ts := newClientServerTest(t, mode, HandlerFunc(func(w ResponseWriter, r *Request) {
		ServeFile(w, r, "testdata/file")
	})).ts
	c := ts.Client()

	var err error

	file, err := os.ReadFile(testFile)
	if err != nil {

		}
	}
}

func TestServerContentTypeSniff(t *testing.T) { run(t, testServerContentTypeSniff) }
func testServerContentTypeSniff(t *testing.T, mode testMode) {
	cst := newClientServerTest(t, mode, HandlerFunc(func(w ResponseWriter, r *Request) {
		i, _ := strconv.Atoi(r.FormValue("i"))
		tt := sniffTests[i]
		n, err := w.Write(tt.data)
		if n != len(tt.data) || err != nil {

}

func newTransportDialTester(t *testing.T, mode testMode) *transportDialTester {
	t.Helper()
	dt := &transportDialTester{
		t:     t,
		dials: make(chan *transportDialTesterConn),
	}
	dt.cst = newClientServerTest(t, mode, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// Write response headers when we receive a request.
		http.NewResponseController(w).EnableFullDuplex()
		w.WriteHeader(200)

	run(t, testMaxInt64ForMultipartFormMaxMemoryOverflow)
}
func testMaxInt64ForMultipartFormMaxMemoryOverflow(t *testing.T, mode testMode) {
	payloadSize := 1 << 10
	cst := newClientServerTest(t, mode, HandlerFunc(func(rw ResponseWriter, req *Request) {
		// The combination of:
		//      MaxInt64 + payloadSize + (internal spare of 10MiB)
		// triggers the overflow. See issue https://golang.org/issue/40430/