Merge branch 'master' into websocket-http2

# Conflicts:
#	http2/transport_test.go

Author: WeidiDeng

Diff for: README.md

@@ -2,17 +2,15 @@
 
 [![Go Reference](https://pkg.go.dev/badge/golang.org/x/net.svg)](https://pkg.go.dev/golang.org/x/net)
 
-This repository holds supplementary Go networking libraries.
+This repository holds supplementary Go networking packages.
 
-## Download/Install
+## Report Issues / Send Patches
 
-The easiest way to install is to run `go get -u golang.org/x/net`. You can
-also manually git clone the repository to `$GOPATH/src/golang.org/x/net`.
+This repository uses Gerrit for code changes. To learn how to submit changes to
+this repository, see https://go.dev/doc/contribute.
 
-## Report Issues / Send Patches
+The git repository is https://go.googlesource.com/net.
 
-This repository uses Gerrit for code changes. To learn how to submit
-changes to this repository, see https://golang.org/doc/contribute.html.
 The main issue tracker for the net repository is located at
-https://github.com/golang/go/issues. Prefix your issue with "x/net:" in the
+https://go.dev/issues. Prefix your issue with "x/net:" in the
 subject line, so it is easy to find.

Diff for: go.mod

@@ -3,8 +3,8 @@ module golang.org/x/net
 go 1.18
 
 require (
-	golang.org/x/crypto v0.27.0
-	golang.org/x/sys v0.25.0
-	golang.org/x/term v0.24.0
-	golang.org/x/text v0.18.0
+	golang.org/x/crypto v0.29.0
+	golang.org/x/sys v0.27.0
+	golang.org/x/term v0.26.0
+	golang.org/x/text v0.20.0
 )

Diff for: go.sum

@@ -1,8 +1,8 @@
-golang.org/x/crypto v0.27.0 h1:GXm2NjJrPaiv/h1tb2UH8QfgC/hOf/+z0p6PT8o1w7A=
-golang.org/x/crypto v0.27.0/go.mod h1:1Xngt8kV6Dvbssa53Ziq6Eqn0HqbZi5Z6R0ZpwQzt70=
-golang.org/x/sys v0.25.0 h1:r+8e+loiHxRqhXVl6ML1nO3l1+oFoWbnlu2Ehimmi34=
-golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/term v0.24.0 h1:Mh5cbb+Zk2hqqXNO7S1iTjEphVL+jb8ZWaqh/g+JWkM=
-golang.org/x/term v0.24.0/go.mod h1:lOBK/LVxemqiMij05LGJ0tzNr8xlmwBRJ81PX6wVLH8=
-golang.org/x/text v0.18.0 h1:XvMDiNzPAl0jr17s6W9lcaIhGUfUORdGCNsuLmPG224=
-golang.org/x/text v0.18.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=
+golang.org/x/crypto v0.29.0 h1:L5SG1JTTXupVV3n6sUqMTeWbjAyfPwoda2DLX8J8FrQ=
+golang.org/x/crypto v0.29.0/go.mod h1:+F4F4N5hv6v38hfeYwTdx20oUvLLc+QfrE9Ax9HtgRg=
+golang.org/x/sys v0.27.0 h1:wBqf8DvsY9Y/2P8gAfPDEYNuS30J4lPHJxXSb/nJZ+s=
+golang.org/x/sys v0.27.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/term v0.26.0 h1:WEQa6V3Gja/BhNxg540hBip/kkaYtRg3cxg4oXSw4AU=
+golang.org/x/term v0.26.0/go.mod h1:Si5m1o57C5nBNQo5z1iq+XDijt21BDBDp2bK0QI8e3E=
+golang.org/x/text v0.20.0 h1:gK/Kv2otX8gz+wn7Rmb3vT96ZwuoxnQlY+HlJVj7Qug=
+golang.org/x/text v0.20.0/go.mod h1:D4IsuqiFMhST5bX19pQ9ikHC2GsaKyk/oF+pn3ducp4=

Diff for: html/doc.go

@@ -78,16 +78,11 @@ example, to process each anchor node in depth-first order:
 	if err != nil {
 		// ...
 	}
-	var f func(*html.Node)
-	f = func(n *html.Node) {
+	for n := range doc.Descendants() {
 		if n.Type == html.ElementNode && n.Data == "a" {
 			// Do something with n...
 		}
-		for c := n.FirstChild; c != nil; c = c.NextSibling {
-			f(c)
-		}
 	}
-	f(doc)
 
 The relevant specifications include:
 https://html.spec.whatwg.org/multipage/syntax.html and

Diff for: html/example_test.go

@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build go1.23
+
 // This example demonstrates parsing HTML data and walking the resulting tree.
 package html_test
 
@@ -11,6 +13,7 @@ import (
 	"strings"
 
 	"golang.org/x/net/html"
+	"golang.org/x/net/html/atom"
 )
 
 func ExampleParse() {
@@ -19,21 +22,17 @@ func ExampleParse() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	var f func(*html.Node)
-	f = func(n *html.Node) {
-		if n.Type == html.ElementNode && n.Data == "a" {
+	for n := range doc.Descendants() {
+		if n.Type == html.ElementNode && n.DataAtom == atom.A {
 			for _, a := range n.Attr {
 				if a.Key == "href" {
 					fmt.Println(a.Val)
 					break
 				}
 			}
 		}
-		for c := n.FirstChild; c != nil; c = c.NextSibling {
-			f(c)
-		}
 	}
-	f(doc)
+
 	// Output:
 	// foo
 	// /bar/baz

Diff for: html/iter.go

@@ -0,0 +1,56 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.23
+
+package html
+
+import "iter"
+
+// Ancestors returns an iterator over the ancestors of n, starting with n.Parent.
+//
+// Mutating a Node or its parents while iterating may have unexpected results.
+func (n *Node) Ancestors() iter.Seq[*Node] {
+	_ = n.Parent // eager nil check
+
+	return func(yield func(*Node) bool) {
+		for p := n.Parent; p != nil && yield(p); p = p.Parent {
+		}
+	}
+}
+
+// ChildNodes returns an iterator over the immediate children of n,
+// starting with n.FirstChild.
+//
+// Mutating a Node or its children while iterating may have unexpected results.
+func (n *Node) ChildNodes() iter.Seq[*Node] {
+	_ = n.FirstChild // eager nil check
+
+	return func(yield func(*Node) bool) {
+		for c := n.FirstChild; c != nil && yield(c); c = c.NextSibling {
+		}
+	}
+
+}
+
+// Descendants returns an iterator over all nodes recursively beneath
+// n, excluding n itself. Nodes are visited in depth-first preorder.
+//
+// Mutating a Node or its descendants while iterating may have unexpected results.
+func (n *Node) Descendants() iter.Seq[*Node] {
+	_ = n.FirstChild // eager nil check
+
+	return func(yield func(*Node) bool) {
+		n.descendants(yield)
+	}
+}
+
+func (n *Node) descendants(yield func(*Node) bool) bool {
+	for c := range n.ChildNodes() {
+		if !yield(c) || !c.descendants(yield) {
+			return false
+		}
+	}
+	return true
+}

Diff for: html/iter_test.go

@@ -0,0 +1,96 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.23
+
+package html
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestNode_ChildNodes(t *testing.T) {
+	tests := []struct {
+		in   string
+		want string
+	}{
+		{"", ""},
+		{"<a></a>", "a"},
+		{"a", "a"},
+		{"<a></a><!--b-->", "a b"},
+		{"a<b></b>c", "a b c"},
+		{"a<b><!--c--></b>d", "a b d"},
+		{"<a><b>c<!--d-->e</b></a>f<!--g--><h>i</h>", "a f g h"},
+	}
+	for _, test := range tests {
+		doc, err := Parse(strings.NewReader(test.in))
+		if err != nil {
+			t.Fatal(err)
+		}
+		// Drill to <html><head></head><body>
+		n := doc.FirstChild.FirstChild.NextSibling
+		var results []string
+		for c := range n.ChildNodes() {
+			results = append(results, c.Data)
+		}
+		if got := strings.Join(results, " "); got != test.want {
+			t.Errorf("ChildNodes = %q, want %q", got, test.want)
+		}
+	}
+}
+
+func TestNode_Descendants(t *testing.T) {
+	tests := []struct {
+		in   string
+		want string
+	}{
+		{"", ""},
+		{"<a></a>", "a"},
+		{"<a><b></b></a>", "a b"},
+		{"<a>b</a>", "a b"},
+		{"<a><!--b--></a>", "a b"},
+		{"<a>b<c></c>d</a>", "a b c d"},
+		{"<a>b<c><!--d--></c>e</a>", "a b c d e"},
+		{"<a><b><c>d<!--e-->f</c></b>g<!--h--><i>j</i></a>", "a b c d e f g h i j"},
+	}
+	for _, test := range tests {
+		doc, err := Parse(strings.NewReader(test.in))
+		if err != nil {
+			t.Fatal(err)
+		}
+		// Drill to <html><head></head><body>
+		n := doc.FirstChild.FirstChild.NextSibling
+		var results []string
+		for c := range n.Descendants() {
+			results = append(results, c.Data)
+		}
+		if got := strings.Join(results, " "); got != test.want {
+			t.Errorf("Descendants = %q; want: %q", got, test.want)
+		}
+	}
+}
+
+func TestNode_Ancestors(t *testing.T) {
+	for _, size := range []int{0, 1, 2, 10, 100, 10_000} {
+		n := buildChain(size)
+		nParents := 0
+		for _ = range n.Ancestors() {
+			nParents++
+		}
+		if nParents != size {
+			t.Errorf("number of Ancestors = %d; want: %d", nParents, size)
+		}
+	}
+}
+
+func buildChain(size int) *Node {
+	child := new(Node)
+	for range size {
+		parent := child
+		child = new(Node)
+		parent.AppendChild(child)
+	}
+	return child
+}

Diff for: html/node.go

@@ -38,6 +38,10 @@ var scopeMarker = Node{Type: scopeMarkerNode}
 // that it looks like "a<b" rather than "a&lt;b". For element nodes, DataAtom
 // is the atom for Data, or zero if Data is not a known tag name.
 //
+// Node trees may be navigated using the link fields (Parent,
+// FirstChild, and so on) or a range loop over iterators such as
+// [Node.Descendants].
+//
 // An empty Namespace implies a "http://www.w3.org/1999/xhtml" namespace.
 // Similarly, "math" is short for "http://www.w3.org/1998/Math/MathML", and
 // "svg" is short for "http://www.w3.org/2000/svg".

Diff for: http2/client_conn_pool.go

@@ -8,8 +8,8 @@ package http2
 
 import (
 	"context"
-	"crypto/tls"
 	"errors"
+	"net"
 	"net/http"
 	"sync"
 )
@@ -158,7 +158,7 @@ func (c *dialCall) dial(ctx context.Context, addr string) {
 // This code decides which ones live or die.
 // The return value used is whether c was used.
 // c is never closed.
-func (p *clientConnPool) addConnIfNeeded(key string, t *Transport, c *tls.Conn) (used bool, err error) {
+func (p *clientConnPool) addConnIfNeeded(key string, t *Transport, c net.Conn) (used bool, err error) {
 	p.mu.Lock()
 	for _, cc := range p.conns[key] {
 		if cc.CanTakeNewRequest() {
@@ -194,8 +194,8 @@ type addConnCall struct {
 	err  error
 }
 
-func (c *addConnCall) run(t *Transport, key string, tc *tls.Conn) {
-	cc, err := t.NewClientConn(tc)
+func (c *addConnCall) run(t *Transport, key string, nc net.Conn) {
+	cc, err := t.NewClientConn(nc)
 
 	p := c.p
 	p.mu.Lock()

Diff for: http2/clientconn_test.go

@@ -10,6 +10,7 @@ package http2
 import (
 	"bytes"
 	"context"
+	"crypto/tls"
 	"fmt"
 	"io"
 	"net/http"
@@ -112,27 +113,40 @@ func newTestClientConnFromClientConn(t *testing.T, cc *ClientConn) *testClientCo
 		cc:    cc,
 		group: cc.t.transportTestHooks.group.(*synctestGroup),
 	}
-	cli, srv := synctestNetPipe(tc.group)
+
+	// srv is the side controlled by the test.
+	var srv *synctestNetConn
+	if cc.tconn == nil {
+		// If cc.tconn is nil, we're being called with a new conn created by the
+		// Transport's client pool. This path skips dialing the server, and we
+		// create a test connection pair here.
+		cc.tconn, srv = synctestNetPipe(tc.group)
+	} else {
+		// If cc.tconn is non-nil, we're in a test which provides a conn to the
+		// Transport via a TLSNextProto hook. Extract the test connection pair.
+		if tc, ok := cc.tconn.(*tls.Conn); ok {
+			// Unwrap any *tls.Conn to the underlying net.Conn,
+			// to avoid dealing with encryption in tests.
+			cc.tconn = tc.NetConn()
+		}
+		srv = cc.tconn.(*synctestNetConn).peer
+	}
+
 	srv.SetReadDeadline(tc.group.Now())
 	srv.autoWait = true
 	tc.netconn = srv
 	tc.enc = hpack.NewEncoder(&tc.encbuf)
-
-	// all writes and reads are finished.
-	//
-	// cli is the ClientConn's side, srv is the side controlled by the test.
-	cc.tconn = cli
 	tc.fr = NewFramer(srv, srv)
 	tc.testConnFramer = testConnFramer{
 		t:   t,
 		fr:  tc.fr,
 		dec: hpack.NewDecoder(initialHeaderTableSize, nil),
 	}
-
 	tc.fr.SetMaxReadFrameSize(10 << 20)
 	t.Cleanup(func() {
 		tc.closeWrite()
 	})
+
 	return tc
 }
 
@@ -503,6 +517,8 @@ func newTestTransport(t *testing.T, opts ...any) *testTransport {
 			o(tr.t1)
 		case func(*Transport):
 			o(tr)
+		case *Transport:
+			tr = o
 		}
 	}
 	tt.tr = tr

Diff for: http2/http2_test.go

@@ -283,3 +283,11 @@ func TestNoUnicodeStrings(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+// must returns v if err is nil, or panics otherwise.
+func must[T any](v T, err error) T {
+	if err != nil {
+		panic(err)
+	}
+	return v
+}