}

		// Calculate input body size with headers
		reqHeaders := r.Header.Clone()
		reqHeaders.Set("Host", r.Host)
		if len(r.TransferEncoding) == 0 {
			reqHeaders.Set("Content-Length", strconv.Itoa(int(r.ContentLength)))
		} else {
			reqHeaders.Set("Transfer-Encoding", strings.Join(r.TransferEncoding, ","))
		}
		inputBytes := reqRecorder.Size()
		for k, v := range reqHeaders {
			inputBytes += len(k) + len(v)
		}

	req.TransferEncoding[0] = "encoding2"

	if req.TransferEncoding[0] != "encoding2" {
		t.Error("expected req.TransferEncoding to be changed")
	}
	if clonedReq.TransferEncoding[0] != "encoding1" {
		t.Error("expected clonedReq.TransferEncoding to be unchanged")
	}
}

// Ensure that Request.Clone works correctly with PathValue.
// See issue 64911.
func TestRequestClonePathValue(t *testing.T) {

		t.Errorf("expected ContentLength of %d; got %d", e, g)
	}
	wantTE := []string{"chunked"}
	if mode == http2Mode {
		wantTE = nil
	}
	if !reflect.DeepEqual(res.TransferEncoding, wantTE) {
		t.Errorf("TransferEncoding = %v; want %v", res.TransferEncoding, wantTE)
	}
	if got, haveCL := res.Header["Content-Length"]; haveCL {
		t.Errorf("Unexpected Content-Length: %q", got)
	}
}

	// also treated as unknown.
	ContentLength int64

	// TransferEncoding lists the transfer encodings from outermost to
	// innermost. An empty list denotes the "identity" encoding.
	// TransferEncoding can usually be ignored; chunked encoding is
	// automatically added and removed as necessary when sending and
	// receiving requests.
	TransferEncoding []string

	// Close indicates whether to close the connection after

			extractedSignedHeaders.Set(header, r.Host)
		case "transfer-encoding":
			// Go http server removes "host" from Request.Header
			extractedSignedHeaders[http.CanonicalHeaderKey(header)] = r.TransferEncoding
		case "content-length":
			// Signature-V4 spec excludes Content-Length from signed headers list for signature calculation.
			// But some clients deviate from this rule. Hence we consider Content-Length for signature

		if r.Method == "GET" && r.FormValue("mode") == "hangup" {
			c, _, _ := w.(http.Hijacker).Hijack()
			c.Close()
			return
		}
		if len(r.TransferEncoding) > 0 {
			t.Errorf("backend got unexpected TransferEncoding: %v", r.TransferEncoding)
		}
		if r.Header.Get("X-Forwarded-For") == "" {
			t.Errorf("didn't get X-Forwarded-For header")
		}
		if c := r.Header.Get("Connection"); c != "" {

			t.Errorf("for %s expected Content-Length header of %q; got %q", url, expected, cl)
		}
		if tl, expected := len(res.TransferEncoding), 0; tl != expected {
			t.Errorf("for %s expected len(res.TransferEncoding) of %d; got %d (%v)",
				url, expected, tl, res.TransferEncoding)
		}
		res.Body.Close()
	}

	// Verify that ErrContentLength is returned
	url := ts.URL + "/?overwrite=1"

// This type is used to avoid extra allocations from cloning and/or populating
// the response Header map and all its 1-element slices.
type extraHeader struct {
	contentType      string
	connection       string
	transferEncoding string
	date             []byte // written if not nil
	contentLength    []byte // written if not nil
}

// Sorted the same as extraHeader.Write's loop.
var extraHeaderKeys = [][]byte{

		addCustomHeaders(req, testCase.headers)

		// Inject faults if specified in testCase.fault
		switch testCase.fault {
		case MissingContentLength:
			req.ContentLength = -1
			req.TransferEncoding = []string{}
		case TooBigObject:
			req.ContentLength = globalMaxObjectSize + 1
		}
		// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.