Update to k8s v1.20

vendor/golang.org/x/net/http2/client_conn_pool.go

@@ -107,6 +107,7 @@ func (p *clientConnPool) getClientConn(req *http.Request, addr string, dialOnMis
 
 // dialCall is an in-flight Transport dial call to a host.
 type dialCall struct {
+	_    incomparable
 	p    *clientConnPool
 	done chan struct{} // closed when done
 	res  *ClientConn   // valid after done is closed
@@ -180,6 +181,7 @@ func (p *clientConnPool) addConnIfNeeded(key string, t *Transport, c *tls.Conn)
 }
 
 type addConnCall struct {
+	_    incomparable
 	p    *clientConnPool
 	done chan struct{} // closed when done
 	err  error
@@ -200,12 +202,6 @@ func (c *addConnCall) run(t *Transport, key string, tc *tls.Conn) {
 	close(c.done)
 }
 
-func (p *clientConnPool) addConn(key string, cc *ClientConn) {
-	p.mu.Lock()
-	p.addConnLocked(key, cc)
-	p.mu.Unlock()
-}
-
 // p.mu must be held
 func (p *clientConnPool) addConnLocked(key string, cc *ClientConn) {
 	for _, v := range p.conns[key] {

vendor/golang.org/x/net/http2/flow.go

@@ -8,6 +8,8 @@ package http2
 
 // flow is the flow control window's size.
 type flow struct {
+	_ incomparable
+
 	// n is the number of DATA bytes we're allowed to send.
 	// A flow is kept both on a conn and a per-stream.
 	n int32

vendor/golang.org/x/net/http2/hpack/huffman.go

@@ -105,7 +105,14 @@ func huffmanDecode(buf *bytes.Buffer, maxLen int, v []byte) error {
 	return nil
 }
 
+// incomparable is a zero-width, non-comparable type. Adding it to a struct
+// makes that struct also non-comparable, and generally doesn't add
+// any size (as long as it's first).
+type incomparable [0]func()
+
 type node struct {
+	_ incomparable
+
 	// children is non-nil for internal nodes
 	children *[256]*node
 

vendor/golang.org/x/net/http2/http2.go

@@ -19,7 +19,6 @@ package http2 // import "golang.org/x/net/http2"
 import (
 	"bufio"
 	"crypto/tls"
-	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -173,11 +172,6 @@ func (s SettingID) String() string {
 	return fmt.Sprintf("UNKNOWN_SETTING_%d", uint16(s))
 }
 
-var (
-	errInvalidHeaderFieldName  = errors.New("http2: invalid header field name")
-	errInvalidHeaderFieldValue = errors.New("http2: invalid header field value")
-)
-
 // validWireHeaderFieldName reports whether v is a valid header field
 // name (key). See httpguts.ValidHeaderName for the base rules.
 //
@@ -247,6 +241,7 @@ func (cw closeWaiter) Wait() {
 // Its buffered writer is lazily allocated as needed, to minimize
 // idle memory usage with many connections.
 type bufferedWriter struct {
+	_  incomparable
 	w  io.Writer     // immutable
 	bw *bufio.Writer // non-nil when data is buffered
 }
@@ -319,6 +314,7 @@ func bodyAllowedForStatus(status int) bool {
 }
 
 type httpError struct {
+	_       incomparable
 	msg     string
 	timeout bool
 }
@@ -382,3 +378,8 @@ func (s *sorter) SortStrings(ss []string) {
 func validPseudoPath(v string) bool {
 	return (len(v) > 0 && v[0] == '/') || v == "*"
 }
+
+// incomparable is a zero-width, non-comparable type. Adding it to a struct
+// makes that struct also non-comparable, and generally doesn't add
+// any size (as long as it's first).
+type incomparable [0]func()

vendor/golang.org/x/net/http2/server.go

@@ -581,13 +581,10 @@ type stream struct {
 	cancelCtx func()
 
 	// owned by serverConn's serve loop:
-	bodyBytes        int64   // body bytes seen so far
-	declBodyBytes    int64   // or -1 if undeclared
-	flow             flow    // limits writing from Handler to client
-	inflow           flow    // what the client is allowed to POST/etc to us
-	parent           *stream // or nil
-	numTrailerValues int64
-	weight           uint8
+	bodyBytes        int64 // body bytes seen so far
+	declBodyBytes    int64 // or -1 if undeclared
+	flow             flow  // limits writing from Handler to client
+	inflow           flow  // what the client is allowed to POST/etc to us
 	state            streamState
 	resetQueued      bool        // RST_STREAM queued for write; set by sc.resetStream
 	gotTrailerHeader bool        // HEADER frame for trailers was seen
@@ -764,6 +761,7 @@ func (sc *serverConn) readFrames() {
 
 // frameWriteResult is the message passed from writeFrameAsync to the serve goroutine.
 type frameWriteResult struct {
+	_   incomparable
 	wr  FrameWriteRequest // what was written (or attempted)
 	err error             // result of the writeFrame call
 }
@@ -774,7 +772,7 @@ type frameWriteResult struct {
 // serverConn.
 func (sc *serverConn) writeFrameAsync(wr FrameWriteRequest) {
 	err := wr.write.writeFrame(sc)
-	sc.wroteFrameCh <- frameWriteResult{wr, err}
+	sc.wroteFrameCh <- frameWriteResult{wr: wr, err: err}
 }
 
 func (sc *serverConn) closeAllStreamsOnConnClose() {
@@ -1164,7 +1162,7 @@ func (sc *serverConn) startFrameWrite(wr FrameWriteRequest) {
 	if wr.write.staysWithinBuffer(sc.bw.Available()) {
 		sc.writingFrameAsync = false
 		err := wr.write.writeFrame(sc)
-		sc.wroteFrame(frameWriteResult{wr, err})
+		sc.wroteFrame(frameWriteResult{wr: wr, err: err})
 	} else {
 		sc.writingFrameAsync = true
 		go sc.writeFrameAsync(wr)
@@ -1696,6 +1694,7 @@ func (sc *serverConn) processData(f *DataFrame) error {
 		if len(data) > 0 {
 			wrote, err := st.body.Write(data)
 			if err != nil {
+				sc.sendWindowUpdate(nil, int(f.Length)-wrote)
 				return streamError(id, ErrCodeStreamClosed)
 			}
 			if wrote != len(data) {
@@ -2022,7 +2021,11 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res
 	}
 	if bodyOpen {
 		if vv, ok := rp.header["Content-Length"]; ok {
-			req.ContentLength, _ = strconv.ParseInt(vv[0], 10, 64)
+			if cl, err := strconv.ParseUint(vv[0], 10, 63); err == nil {
+				req.ContentLength = int64(cl)
+			} else {
+				req.ContentLength = 0
+			}
 		} else {
 			req.ContentLength = -1
 		}
@@ -2060,7 +2063,7 @@ func (sc *serverConn) newWriterAndRequestNoBody(st *stream, rp requestParam) (*r
 	var trailer http.Header
 	for _, v := range rp.header["Trailer"] {
 		for _, key := range strings.Split(v, ",") {
-			key = http.CanonicalHeaderKey(strings.TrimSpace(key))
+			key = http.CanonicalHeaderKey(textproto.TrimString(key))
 			switch key {
 			case "Transfer-Encoding", "Trailer", "Content-Length":
 				// Bogus. (copy of http1 rules)
@@ -2278,6 +2281,7 @@ func (sc *serverConn) sendWindowUpdate32(st *stream, n int32) {
 // requestBody is the Handler's Request.Body type.
 // Read and Close may be called concurrently.
 type requestBody struct {
+	_             incomparable
 	stream        *stream
 	conn          *serverConn
 	closed        bool  // for use by Close only
@@ -2404,9 +2408,8 @@ func (rws *responseWriterState) writeChunk(p []byte) (n int, err error) {
 		var ctype, clen string
 		if clen = rws.snapHeader.Get("Content-Length"); clen != "" {
 			rws.snapHeader.Del("Content-Length")
-			clen64, err := strconv.ParseInt(clen, 10, 64)
-			if err == nil && clen64 >= 0 {
-				rws.sentContentLen = clen64
+			if cl, err := strconv.ParseUint(clen, 10, 63); err == nil {
+				rws.sentContentLen = int64(cl)
 			} else {
 				clen = ""
 			}

vendor/golang.org/x/net/http2/transport.go

@@ -93,7 +93,7 @@ type Transport struct {
 	// send in the initial settings frame. It is how many bytes
 	// of response headers are allowed. Unlike the http2 spec, zero here
 	// means to use a default limit (currently 10MB). If you actually
-	// want to advertise an ulimited value to the peer, Transport
+	// want to advertise an unlimited value to the peer, Transport
 	// interprets the highest possible value here (0xffffffff or 1<<32-1)
 	// to mean no limit.
 	MaxHeaderListSize uint32
@@ -108,6 +108,19 @@ type Transport struct {
 	// waiting for their turn.
 	StrictMaxConcurrentStreams bool
 
+	// ReadIdleTimeout is the timeout after which a health check using ping
+	// frame will be carried out if no frame is received on the connection.
+	// Note that a ping response will is considered a received frame, so if
+	// there is no other traffic on the connection, the health check will
+	// be performed every ReadIdleTimeout interval.
+	// If zero, no health check is performed.
+	ReadIdleTimeout time.Duration
+
+	// PingTimeout is the timeout after which the connection will be closed
+	// if a response to Ping is not received.
+	// Defaults to 15s.
+	PingTimeout time.Duration
+
 	// t1, if non-nil, is the standard library Transport using
 	// this transport. Its settings are used (but not its
 	// RoundTrip method, etc).
@@ -131,14 +144,31 @@ func (t *Transport) disableCompression() bool {
 	return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
 }
 
+func (t *Transport) pingTimeout() time.Duration {
+	if t.PingTimeout == 0 {
+		return 15 * time.Second
+	}
+	return t.PingTimeout
+
+}
+
 // ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2.
 // It returns an error if t1 has already been HTTP/2-enabled.
+//
+// Use ConfigureTransports instead to configure the HTTP/2 Transport.
 func ConfigureTransport(t1 *http.Transport) error {
-	_, err := configureTransport(t1)
+	_, err := ConfigureTransports(t1)
 	return err
 }
 
-func configureTransport(t1 *http.Transport) (*Transport, error) {
+// ConfigureTransports configures a net/http HTTP/1 Transport to use HTTP/2.
+// It returns a new HTTP/2 Transport for further configuration.
+// It returns an error if t1 has already been HTTP/2-enabled.
+func ConfigureTransports(t1 *http.Transport) (*Transport, error) {
+	return configureTransports(t1)
+}
+
+func configureTransports(t1 *http.Transport) (*Transport, error) {
 	connPool := new(clientConnPool)
 	t2 := &Transport{
 		ConnPool: noDialClientConnPool{connPool},
@@ -227,6 +257,7 @@ type ClientConn struct {
 	br              *bufio.Reader
 	fr              *Framer
 	lastActive      time.Time
+	lastIdle        time.Time // time last idle
 	// Settings from peer: (also guarded by mu)
 	maxFrameSize          uint32
 	maxConcurrentStreams  uint32
@@ -667,6 +698,7 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 	cc.inflow.add(transportDefaultConnFlow + initialWindowSize)
 	cc.bw.Flush()
 	if cc.werr != nil {
+		cc.Close()
 		return nil, cc.werr
 	}
 
@@ -674,6 +706,20 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 	return cc, nil
 }
 
+func (cc *ClientConn) healthCheck() {
+	pingTimeout := cc.t.pingTimeout()
+	// We don't need to periodically ping in the health check, because the readLoop of ClientConn will
+	// trigger the healthCheck again if there is no frame received.
+	ctx, cancel := context.WithTimeout(context.Background(), pingTimeout)
+	defer cancel()
+	err := cc.Ping(ctx)
+	if err != nil {
+		cc.closeForLostPing()
+		cc.t.connPool().MarkDead(cc)
+		return
+	}
+}
+
 func (cc *ClientConn) setGoAway(f *GoAwayFrame) {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
@@ -736,7 +782,8 @@ func (cc *ClientConn) idleStateLocked() (st clientConnIdleState) {
 	}
 
 	st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && maxConcurrentOkay &&
-		int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32
+		int64(cc.nextStreamID)+2*int64(cc.pendingRequests) < math.MaxInt32 &&
+		!cc.tooIdleLocked()
 	st.freshConn = cc.nextStreamID == 1 && st.canTakeNewRequest
 	return
 }
@@ -746,6 +793,16 @@ func (cc *ClientConn) canTakeNewRequestLocked() bool {
 	return st.canTakeNewRequest
 }
 
+// tooIdleLocked reports whether this connection has been been sitting idle
+// for too much wall time.
+func (cc *ClientConn) tooIdleLocked() bool {
+	// The Round(0) strips the monontonic clock reading so the
+	// times are compared based on their wall time. We don't want
+	// to reuse a connection that's been sitting idle during
+	// VM/laptop suspend if monotonic time was also frozen.
+	return cc.idleTimeout != 0 && !cc.lastIdle.IsZero() && time.Since(cc.lastIdle.Round(0)) > cc.idleTimeout
+}
+
 // onIdleTimeout is called from a time.AfterFunc goroutine. It will
 // only be called when we're idle, but because we're coming from a new
 // goroutine, there could be a new request coming in at the same time,
@@ -834,14 +891,12 @@ func (cc *ClientConn) sendGoAway() error {
 	return nil
 }
 
-// Close closes the client connection immediately.
-//
-// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
-func (cc *ClientConn) Close() error {
+// closes the client connection immediately. In-flight requests are interrupted.
+// err is sent to streams.
+func (cc *ClientConn) closeForError(err error) error {
 	cc.mu.Lock()
 	defer cc.cond.Broadcast()
 	defer cc.mu.Unlock()
-	err := errors.New("http2: client connection force closed via ClientConn.Close")
 	for id, cs := range cc.streams {
 		select {
 		case cs.resc <- resAndError{err: err}:
@@ -854,6 +909,20 @@ func (cc *ClientConn) Close() error {
 	return cc.tconn.Close()
 }
 
+// Close closes the client connection immediately.
+//
+// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead.
+func (cc *ClientConn) Close() error {
+	err := errors.New("http2: client connection force closed via ClientConn.Close")
+	return cc.closeForError(err)
+}
+
+// closes the client connection immediately. In-flight requests are interrupted.
+func (cc *ClientConn) closeForLostPing() error {
+	err := errors.New("http2: client connection lost")
+	return cc.closeForError(err)
+}
+
 const maxAllocFrameSize = 512 << 10
 
 // frameBuffer returns a scratch buffer suitable for writing DATA frames.
@@ -904,7 +973,7 @@ func commaSeparatedTrailers(req *http.Request) (string, error) {
 		k = http.CanonicalHeaderKey(k)
 		switch k {
 		case "Transfer-Encoding", "Trailer", "Content-Length":
-			return "", &badStringError{"invalid Trailer key", k}
+			return "", fmt.Errorf("invalid Trailer key %q", k)
 		}
 		keys = append(keys, k)
 	}
@@ -1021,6 +1090,15 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 	bodyWriter := cc.t.getBodyWriterState(cs, body)
 	cs.on100 = bodyWriter.on100
 
+	defer func() {
+		cc.wmu.Lock()
+		werr := cc.werr
+		cc.wmu.Unlock()
+		if werr != nil {
+			cc.Close()
+		}
+	}()
+
 	cc.wmu.Lock()
 	endStream := !hasBody && !hasTrailers
 	werr := cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs)
@@ -1070,6 +1148,9 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 			// we can keep it.
 			bodyWriter.cancel()
 			cs.abortRequestBodyWrite(errStopReqBodyWrite)
+			if hasBody && !bodyWritten {
+				<-bodyWriter.resc
+			}
 		}
 		if re.err != nil {
 			cc.forgetStreamID(cs.ID)
@@ -1090,6 +1171,7 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 			} else {
 				bodyWriter.cancel()
 				cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
+				<-bodyWriter.resc
 			}
 			cc.forgetStreamID(cs.ID)
 			return nil, cs.getStartedWrite(), errTimeout
@@ -1099,6 +1181,7 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 			} else {
 				bodyWriter.cancel()
 				cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
+				<-bodyWriter.resc
 			}
 			cc.forgetStreamID(cs.ID)
 			return nil, cs.getStartedWrite(), ctx.Err()
@@ -1108,6 +1191,7 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 			} else {
 				bodyWriter.cancel()
 				cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel)
+				<-bodyWriter.resc
 			}
 			cc.forgetStreamID(cs.ID)
 			return nil, cs.getStartedWrite(), errRequestCanceled
@@ -1117,6 +1201,7 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 			// forgetStreamID.
 			return nil, cs.getStartedWrite(), cs.resetErr
 		case err := <-bodyWriter.resc:
+			bodyWritten = true
 			// Prefer the read loop's response, if available. Issue 16102.
 			select {
 			case re := <-readLoopResCh:
@@ -1127,7 +1212,6 @@ func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAf
 				cc.forgetStreamID(cs.ID)
 				return nil, cs.getStartedWrite(), err
 			}
-			bodyWritten = true
 			if d := cc.responseHeaderTimeout(); d != 0 {
 				timer := time.NewTimer(d)
 				defer timer.Stop()
@@ -1150,6 +1234,7 @@ func (cc *ClientConn) awaitOpenSlotForRequest(req *http.Request) error {
 			}
 			return errClientConnUnusable
 		}
+		cc.lastIdle = time.Time{}
 		if int64(len(cc.streams))+1 <= int64(cc.maxConcurrentStreams) {
 			if waitingForConn != nil {
 				close(waitingForConn)
@@ -1381,13 +1466,6 @@ func (cs *clientStream) awaitFlowControl(maxBytes int) (taken int32, err error)
 	}
 }
 
-type badStringError struct {
-	what string
-	str  string
-}
-
-func (e *badStringError) Error() string { return fmt.Sprintf("%s %q", e.what, e.str) }
-
 // requires cc.mu be held.
 func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) {
 	cc.hbuf.Reset()
@@ -1603,6 +1681,7 @@ func (cc *ClientConn) writeHeader(name, value string) {
 }
 
 type resAndError struct {
+	_   incomparable
 	res *http.Response
 	err error
 }
@@ -1638,6 +1717,7 @@ func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream {
 		delete(cc.streams, id)
 		if len(cc.streams) == 0 && cc.idleTimer != nil {
 			cc.idleTimer.Reset(cc.idleTimeout)
+			cc.lastIdle = time.Now()
 		}
 		close(cs.done)
 		// Wake up checkResetOrDone via clientStream.awaitFlowControl and
@@ -1649,6 +1729,7 @@ func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream {
 
 // clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop.
 type clientConnReadLoop struct {
+	_             incomparable
 	cc            *ClientConn
 	closeWhenIdle bool
 }
@@ -1728,8 +1809,17 @@ func (rl *clientConnReadLoop) run() error {
 	rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse
 	gotReply := false // ever saw a HEADERS reply
 	gotSettings := false
+	readIdleTimeout := cc.t.ReadIdleTimeout
+	var t *time.Timer
+	if readIdleTimeout != 0 {
+		t = time.AfterFunc(readIdleTimeout, cc.healthCheck)
+		defer t.Stop()
+	}
 	for {
 		f, err := cc.fr.ReadFrame()
+		if t != nil {
+			t.Reset(readIdleTimeout)
+		}
 		if err != nil {
 			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
 		}
@@ -1878,7 +1968,9 @@ func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFra
 		return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header")
 	}
 
-	header := make(http.Header)
+	regularFields := f.RegularFields()
+	strs := make([]string, len(regularFields))
+	header := make(http.Header, len(regularFields))
 	res := &http.Response{
 		Proto:      "HTTP/2.0",
 		ProtoMajor: 2,
@@ -1886,7 +1978,7 @@ func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFra
 		StatusCode: statusCode,
 		Status:     status + " " + http.StatusText(statusCode),
 	}
-	for _, hf := range f.RegularFields() {
+	for _, hf := range regularFields {
 		key := http.CanonicalHeaderKey(hf.Name)
 		if key == "Trailer" {
 			t := res.Trailer
@@ -1898,7 +1990,18 @@ func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFra
 				t[http.CanonicalHeaderKey(v)] = nil
 			})
 		} else {
-			header[key] = append(header[key], hf.Value)
+			vv := header[key]
+			if vv == nil && len(strs) > 0 {
+				// More than likely this will be a single-element key.
+				// Most headers aren't multi-valued.
+				// Set the capacity on strs[0] to 1, so any future append
+				// won't extend the slice into the other strings.
+				vv, strs = strs[:1:1], strs[1:]
+				vv[0] = hf.Value
+				header[key] = vv
+			} else {
+				header[key] = append(vv, hf.Value)
+			}
 		}
 	}
 
@@ -1928,8 +2031,8 @@ func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFra
 	if !streamEnded || isHead {
 		res.ContentLength = -1
 		if clens := res.Header["Content-Length"]; len(clens) == 1 {
-			if clen64, err := strconv.ParseInt(clens[0], 10, 64); err == nil {
-				res.ContentLength = clen64
+			if cl, err := strconv.ParseUint(clens[0], 10, 63); err == nil {
+				res.ContentLength = int64(cl)
 			} else {
 				// TODO: care? unlike http/1, it won't mess up our framing, so it's
 				// more safe smuggling-wise to ignore.
@@ -2184,8 +2287,6 @@ func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 	return nil
 }
 
-var errInvalidTrailers = errors.New("http2: invalid trailers")
-
 func (rl *clientConnReadLoop) endStream(cs *clientStream) {
 	// TODO: check that any declared content-length matches, like
 	// server.go's (*stream).endStream method.
@@ -2416,7 +2517,6 @@ func (cc *ClientConn) writeStreamReset(streamID uint32, code ErrCode, err error)
 var (
 	errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit")
 	errRequestHeaderListSize  = errors.New("http2: request header list larger than peer's advertised limit")
-	errPseudoTrailers         = errors.New("http2: invalid pseudo header in trailers")
 )
 
 func (cc *ClientConn) logf(format string, args ...interface{}) {
@@ -2450,11 +2550,13 @@ func strSliceContains(ss []string, s string) bool {
 
 type erringRoundTripper struct{ err error }
 
+func (rt erringRoundTripper) RoundTripErr() error                             { return rt.err }
 func (rt erringRoundTripper) RoundTrip(*http.Request) (*http.Response, error) { return nil, rt.err }
 
 // gzipReader wraps a response body so it can lazily
 // call gzip.NewReader on the first call to Read
 type gzipReader struct {
+	_    incomparable
 	body io.ReadCloser // underlying Response.Body
 	zr   *gzip.Reader  // lazily-initialized gzip reader
 	zerr error         // sticky error