git-codereview/util_test.go - review - Git at Google

 // Copyright 2014 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.

 package main

 import (
 	"bytes"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"reflect"
 	"strings"
 	"sync"
 	"testing"
 )

 var gitversion = "unknown git version" // git version for error logs

 type gitTest struct {
 	pwd         string // current directory before test
 	tmpdir      string // temporary directory holding repos
 	server      string // server repo root
 	client      string // client repo root
 	nwork       int    // number of calls to work method
 	nworkServer int    // number of calls to serverWork method
 	nworkOther  int    // number of calls to serverWorkUnrelated method
 }

 // resetReadOnlyFlagAll resets windows read-only flag
 // set on path and any children it contains.
 // The flag is set by git and has to be removed.
 // os.Remove refuses to remove files with read-only flag set.
 func resetReadOnlyFlagAll(path string) error {
 	fi, err := os.Stat(path)
 	if err != nil {
 		return err
 	}

 	if !fi.IsDir() {
 		return os.Chmod(path, 0666)
 	}

 	fd, err := os.Open(path)
 	if err != nil {
 		return err
 	}
 	defer fd.Close()

 	names, _ := fd.Readdirnames(-1)
 	for _, name := range names {
 		resetReadOnlyFlagAll(path + string(filepath.Separator) + name)
 	}
 	return nil
 }

 func (gt *gitTest) done() {
 	os.Chdir(gt.pwd) // change out of gt.tmpdir first, otherwise following os.RemoveAll fails on windows
 	resetReadOnlyFlagAll(gt.tmpdir)
 	os.RemoveAll(gt.tmpdir)
 	cachedConfig = nil
 }

 // doWork simulates commit 'n' touching 'file' in 'dir'
 func doWork(t *testing.T, n int, dir, file, changeid string) {
 	write(t, dir+"/"+file, fmt.Sprintf("new content %d", n))
 	trun(t, dir, "git", "add", file)
 	suffix := ""
 	if n > 1 {
 		suffix = fmt.Sprintf(" #%d", n)
 	}
 	msg := fmt.Sprintf("msg%s\n\nChange-Id: I%d%s\n", suffix, n, changeid)
 	trun(t, dir, "git", "commit", "-m", msg)
 }

 func (gt *gitTest) work(t *testing.T) {
 	if gt.nwork == 0 {
 		trun(t, gt.client, "git", "checkout", "-b", "work")
 		trun(t, gt.client, "git", "branch", "--set-upstream-to", "origin/master")
 		trun(t, gt.client, "git", "tag", "work") // make sure commands do the right thing when there is a tag of the same name
 	}

 	// make local change on client
 	gt.nwork++
 	doWork(t, gt.nwork, gt.client, "file", "23456789")
 }

 func (gt *gitTest) serverWork(t *testing.T) {
 	// make change on server
 	// duplicating the sequence of changes in gt.work to simulate them
 	// having gone through Gerrit and submitted with possibly
 	// different commit hashes but the same content.
 	gt.nworkServer++
 	doWork(t, gt.nworkServer, gt.server, "file", "23456789")
 }

 func (gt *gitTest) serverWorkUnrelated(t *testing.T) {
 	// make unrelated change on server
 	// this makes history different on client and server
 	gt.nworkOther++
 	doWork(t, gt.nworkOther, gt.server, "otherfile", "9999")
 }

 func newGitTest(t *testing.T) (gt *gitTest) {
 	// The Linux builders seem not to have git in their paths.
 	// That makes this whole repo a bit useless on such systems,
 	// but make sure the tests don't fail.
 	_, err := exec.LookPath("git")
 	if err != nil {
 		t.Skip("cannot find git in path: %v", err)
 	}

 	tmpdir, err := ioutil.TempDir("", "git-codereview-test")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer func() {
 		if gt == nil {
 			os.RemoveAll(tmpdir)
 		}
 	}()

 	gitversion = trun(t, tmpdir, "git", "--version")

 	server := tmpdir + "/git-origin"

 	mkdir(t, server)
 	write(t, server+"/file", "this is master")
 	write(t, server+"/.gitattributes", "* -text\n")
 	trun(t, server, "git", "init", ".")
 	trun(t, server, "git", "config", "user.name", "gopher")
 	trun(t, server, "git", "config", "user.email", "gopher@example.com")
 	trun(t, server, "git", "add", "file", ".gitattributes")
 	trun(t, server, "git", "commit", "-m", "on master")

 	for _, name := range []string{"dev.branch", "release.branch"} {
 		trun(t, server, "git", "checkout", "master")
 		trun(t, server, "git", "checkout", "-b", name)
 		write(t, server+"/file."+name, "this is "+name)
 		trun(t, server, "git", "add", "file."+name)
 		trun(t, server, "git", "commit", "-m", "on "+name)
 	}
 	trun(t, server, "git", "checkout", "master")

 	client := tmpdir + "/git-client"
 	mkdir(t, client)
 	trun(t, client, "git", "clone", server, ".")
 	trun(t, client, "git", "config", "user.name", "gopher")
 	trun(t, client, "git", "config", "user.email", "gopher@example.com")

 	// write stub hooks to keep installHook from installing its own.
 	// If it installs its own, git will look for git-codereview on the current path
 	// and may find an old git-codereview that does just about anything.
 	// In any event, we wouldn't be testing what we want to test.
 	// Tests that want to exercise hooks need to arrange for a git-codereview
 	// in the path and replace these with the real ones.
 	for _, h := range hookFiles {
 		write(t, client+"/.git/hooks/"+h, "#!/bin/bash\nexit 0\n")
 	}

 	trun(t, client, "git", "config", "core.editor", "false")
 	pwd, err := os.Getwd()
 	if err != nil {
 		t.Fatal(err)
 	}

 	if err := os.Chdir(client); err != nil {
 		t.Fatal(err)
 	}

 	return &gitTest{
 		pwd:    pwd,
 		tmpdir: tmpdir,
 		server: server,
 		client: client,
 	}
 }

 func (gt *gitTest) enableGerrit(t *testing.T) {
 	write(t, gt.server+"/codereview.cfg", "gerrit: myserver\n")
 	trun(t, gt.server, "git", "add", "codereview.cfg")
 	trun(t, gt.server, "git", "commit", "-m", "add gerrit")
 	trun(t, gt.client, "git", "pull", "-r")
 }

 func (gt *gitTest) removeStubHooks() {
 	for _, h := range hookFiles {
 		os.RemoveAll(gt.client + "/.git/hooks/" + h)
 	}
 }

 func mkdir(t *testing.T, dir string) {
 	if err := os.Mkdir(dir, 0777); err != nil {
 		t.Fatal(err)
 	}
 }

 func chdir(t *testing.T, dir string) {
 	if err := os.Chdir(dir); err != nil {
 		t.Fatal(err)
 	}
 }

 func write(t *testing.T, file, data string) {
 	if err := ioutil.WriteFile(file, []byte(data), 0666); err != nil {
 		t.Fatal(err)
 	}
 }

 func read(t *testing.T, file string) []byte {
 	b, err := ioutil.ReadFile(file)
 	if err != nil {
 		t.Fatal(err)
 	}
 	return b
 }

 func remove(t *testing.T, file string) {
 	if err := os.RemoveAll(file); err != nil {
 		t.Fatal(err)
 	}
 }

 func trun(t *testing.T, dir string, cmdline ...string) string {
 	cmd := exec.Command(cmdline[0], cmdline[1:]...)
 	cmd.Dir = dir
 	out, err := cmd.CombinedOutput()
 	if err != nil {
 		if cmdline[0] == "git" {
 			t.Fatalf("in %s/, ran %s with %s:\n%v\n%s", filepath.Base(dir), cmdline, gitversion, err, out)
 		}
 		t.Fatalf("in %s/, ran %s: %v\n%s", filepath.Base(dir), cmdline, err, out)
 	}
 	return string(out)
 }

 // fromSlash is like filepath.FromSlash, but it ignores ! at the start of the path
 // and " (staged)" at the end.
 func fromSlash(path string) string {
 	if len(path) > 0 && path[0] == '!' {
 		return "!" + fromSlash(path[1:])
 	}
 	if strings.HasSuffix(path, " (staged)") {
 		return fromSlash(path[:len(path)-len(" (staged)")]) + " (staged)"
 	}
 	return filepath.FromSlash(path)
 }

 var (
 	runLog     []string
 	testStderr *bytes.Buffer
 	testStdout *bytes.Buffer
 	died       bool
 )

 var mainCanDie bool

 func testMainDied(t *testing.T, args ...string) {
 	mainCanDie = true
 	testMain(t, args...)
 	if !died {
 		t.Fatalf("expected to die, did not\nstdout:\n%sstderr:\n%s", testStdout, testStderr)
 	}
 }

 func testMainCanDie(t *testing.T, args ...string) {
 	mainCanDie = true
 	testMain(t, args...)
 }

 func testMain(t *testing.T, args ...string) {
 	*noRun = false
 	*verbose = 0
 	cachedConfig = nil

 	t.Logf("git-codereview %s", strings.Join(args, " "))

 	canDie := mainCanDie
 	mainCanDie = false // reset for next invocation

 	defer func() {
 		runLog = runLogTrap
 		testStdout = stdoutTrap
 		testStderr = stderrTrap

 		dieTrap = nil
 		runLogTrap = nil
 		stdoutTrap = nil
 		stderrTrap = nil
 		if err := recover(); err != nil {
 			if died && canDie {
 				return
 			}
 			var msg string
 			if died {
 				msg = "died"
 			} else {
 				msg = fmt.Sprintf("panic: %v", err)
 			}
 			t.Fatalf("%s\nstdout:\n%sstderr:\n%s", msg, testStdout, testStderr)
 		}
 	}()

 	dieTrap = func() {
 		died = true
 		panic("died")
 	}
 	died = false
 	runLogTrap = []string{} // non-nil, to trigger saving of commands
 	stdoutTrap = new(bytes.Buffer)
 	stderrTrap = new(bytes.Buffer)

 	os.Args = append([]string{"git-codereview"}, args...)
 	main()
 }

 func testRan(t *testing.T, cmds ...string) {
 	if cmds == nil {
 		cmds = []string{}
 	}
 	if !reflect.DeepEqual(runLog, cmds) {
 		t.Errorf("ran:\n%s", strings.Join(runLog, "\n"))
 		t.Errorf("wanted:\n%s", strings.Join(cmds, "\n"))
 	}
 }

 func testPrinted(t *testing.T, buf *bytes.Buffer, name string, messages ...string) {
 	all := buf.String()
 	var errors bytes.Buffer
 	for _, msg := range messages {
 		if strings.HasPrefix(msg, "!") {
 			if strings.Contains(all, msg[1:]) {
 				fmt.Fprintf(&errors, "%s does (but should not) contain %q\n", name, msg[1:])
 			}
 			continue
 		}
 		if !strings.Contains(all, msg) {
 			fmt.Fprintf(&errors, "%s does not contain %q\n", name, msg)
 		}
 	}
 	if errors.Len() > 0 {
 		t.Fatalf("wrong output\n%s%s:\n%s", &errors, name, all)
 	}
 }

 func testPrintedStdout(t *testing.T, messages ...string) {
 	testPrinted(t, testStdout, "stdout", messages...)
 }

 func testPrintedStderr(t *testing.T, messages ...string) {
 	testPrinted(t, testStderr, "stderr", messages...)
 }

 func testNoStdout(t *testing.T) {
 	if testStdout.Len() != 0 {
 		t.Fatalf("unexpected stdout:\n%s", testStdout)
 	}
 }

 func testNoStderr(t *testing.T) {
 	if testStderr.Len() != 0 {
 		t.Fatalf("unexpected stderr:\n%s", testStderr)
 	}
 }

 type gerritServer struct {
 	l     net.Listener
 	mu    sync.Mutex
 	reply map[string]gerritReply
 }

 func newGerritServer(t *testing.T) *gerritServer {
 	l, err := net.Listen("tcp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatalf("starting fake gerrit: %v", err)
 	}

 	auth.host = l.Addr().String()
 	auth.url = "http://" + auth.host
 	auth.project = "proj"
 	auth.user = "gopher"
 	auth.password = "PASSWORD"

 	s := &gerritServer{l: l, reply: make(map[string]gerritReply)}
 	go http.Serve(l, s)
 	return s
 }

 func (s *gerritServer) done() {
 	s.l.Close()
 	auth.host = ""
 	auth.url = ""
 	auth.project = ""
 	auth.user = ""
 	auth.password = ""
 }

 type gerritReply struct {
 	status int
 	body   string
 	json   interface{}
 	f      func() gerritReply
 }

 func (s *gerritServer) setReply(path string, reply gerritReply) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	s.reply[path] = reply
 }

 func (s *gerritServer) setJSON(id, json string) {
 	s.setReply("/a/changes/proj~master~"+id, gerritReply{body: ")]}'\n" + json})
 }

 func (s *gerritServer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 	reply, ok := s.reply[req.URL.Path]
 	if !ok {
 		http.NotFound(w, req)
 		return
 	}
 	if reply.f != nil {
 		reply = reply.f()
 	}
 	if reply.status != 0 {
 		w.WriteHeader(reply.status)
 	}
 	if reply.json != nil {
 		body, err := json.Marshal(reply.json)
 		if err != nil {
 			dief("%v", err)
 		}
 		reply.body = ")]}'\n" + string(body)
 	}
 	if len(reply.body) > 0 {
 		w.Write([]byte(reply.body))
 	}
 }
	// Copyright 2014 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.

	package main

	import (
	"bytes"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
	"reflect"
	"strings"
	"sync"
	"testing"
	)

	var gitversion = "unknown git version" // git version for error logs

	type gitTest struct {
	pwd string // current directory before test
	tmpdir string // temporary directory holding repos
	server string // server repo root
	client string // client repo root
	nwork int // number of calls to work method
	nworkServer int // number of calls to serverWork method
	nworkOther int // number of calls to serverWorkUnrelated method
	}

	// resetReadOnlyFlagAll resets windows read-only flag
	// set on path and any children it contains.
	// The flag is set by git and has to be removed.
	// os.Remove refuses to remove files with read-only flag set.
	func resetReadOnlyFlagAll(path string) error {
	fi, err := os.Stat(path)
	if err != nil {
	return err
	}

	if !fi.IsDir() {
	return os.Chmod(path, 0666)
	}

	fd, err := os.Open(path)
	if err != nil {
	return err
	}
	defer fd.Close()

	names, _ := fd.Readdirnames(-1)
	for _, name := range names {
	resetReadOnlyFlagAll(path + string(filepath.Separator) + name)
	}
	return nil
	}

	func (gt *gitTest) done() {
	os.Chdir(gt.pwd) // change out of gt.tmpdir first, otherwise following os.RemoveAll fails on windows
	resetReadOnlyFlagAll(gt.tmpdir)
	os.RemoveAll(gt.tmpdir)
	cachedConfig = nil
	}

	// doWork simulates commit 'n' touching 'file' in 'dir'
	func doWork(t *testing.T, n int, dir, file, changeid string) {
	write(t, dir+"/"+file, fmt.Sprintf("new content %d", n))
	trun(t, dir, "git", "add", file)
	suffix := ""
	if n > 1 {
	suffix = fmt.Sprintf(" #%d", n)
	}
	msg := fmt.Sprintf("msg%s\n\nChange-Id: I%d%s\n", suffix, n, changeid)
	trun(t, dir, "git", "commit", "-m", msg)
	}

	func (gt gitTest) work(t testing.T) {
	if gt.nwork == 0 {
	trun(t, gt.client, "git", "checkout", "-b", "work")
	trun(t, gt.client, "git", "branch", "--set-upstream-to", "origin/master")
	trun(t, gt.client, "git", "tag", "work") // make sure commands do the right thing when there is a tag of the same name
	}

	// make local change on client
	gt.nwork++
	doWork(t, gt.nwork, gt.client, "file", "23456789")
	}

	func (gt gitTest) serverWork(t testing.T) {
	// make change on server
	// duplicating the sequence of changes in gt.work to simulate them
	// having gone through Gerrit and submitted with possibly
	// different commit hashes but the same content.
	gt.nworkServer++
	doWork(t, gt.nworkServer, gt.server, "file", "23456789")
	}

	func (gt gitTest) serverWorkUnrelated(t testing.T) {
	// make unrelated change on server
	// this makes history different on client and server
	gt.nworkOther++
	doWork(t, gt.nworkOther, gt.server, "otherfile", "9999")
	}

	func newGitTest(t testing.T) (gt gitTest) {
	// The Linux builders seem not to have git in their paths.
	// That makes this whole repo a bit useless on such systems,
	// but make sure the tests don't fail.
	_, err := exec.LookPath("git")
	if err != nil {
	t.Skip("cannot find git in path: %v", err)
	}

	tmpdir, err := ioutil.TempDir("", "git-codereview-test")
	if err != nil {
	t.Fatal(err)
	}
	defer func() {
	if gt == nil {
	os.RemoveAll(tmpdir)
	}
	}()

	gitversion = trun(t, tmpdir, "git", "--version")

	server := tmpdir + "/git-origin"

	mkdir(t, server)
	write(t, server+"/file", "this is master")
	write(t, server+"/.gitattributes", "* -text\n")
	trun(t, server, "git", "init", ".")
	trun(t, server, "git", "config", "user.name", "gopher")
	trun(t, server, "git", "config", "user.email", "gopher@example.com")
	trun(t, server, "git", "add", "file", ".gitattributes")
	trun(t, server, "git", "commit", "-m", "on master")

	for _, name := range []string{"dev.branch", "release.branch"} {
	trun(t, server, "git", "checkout", "master")
	trun(t, server, "git", "checkout", "-b", name)
	write(t, server+"/file."+name, "this is "+name)
	trun(t, server, "git", "add", "file."+name)
	trun(t, server, "git", "commit", "-m", "on "+name)
	}
	trun(t, server, "git", "checkout", "master")

	client := tmpdir + "/git-client"
	mkdir(t, client)
	trun(t, client, "git", "clone", server, ".")
	trun(t, client, "git", "config", "user.name", "gopher")
	trun(t, client, "git", "config", "user.email", "gopher@example.com")

	// write stub hooks to keep installHook from installing its own.
	// If it installs its own, git will look for git-codereview on the current path
	// and may find an old git-codereview that does just about anything.
	// In any event, we wouldn't be testing what we want to test.
	// Tests that want to exercise hooks need to arrange for a git-codereview
	// in the path and replace these with the real ones.
	for _, h := range hookFiles {
	write(t, client+"/.git/hooks/"+h, "#!/bin/bash\nexit 0\n")
	}

	trun(t, client, "git", "config", "core.editor", "false")
	pwd, err := os.Getwd()
	if err != nil {
	t.Fatal(err)
	}

	if err := os.Chdir(client); err != nil {
	t.Fatal(err)
	}

	return &gitTest{
	pwd: pwd,
	tmpdir: tmpdir,
	server: server,
	client: client,
	}
	}

	func (gt gitTest) enableGerrit(t testing.T) {
	write(t, gt.server+"/codereview.cfg", "gerrit: myserver\n")
	trun(t, gt.server, "git", "add", "codereview.cfg")
	trun(t, gt.server, "git", "commit", "-m", "add gerrit")
	trun(t, gt.client, "git", "pull", "-r")
	}

	func (gt *gitTest) removeStubHooks() {
	for _, h := range hookFiles {
	os.RemoveAll(gt.client + "/.git/hooks/" + h)
	}
	}

	func mkdir(t *testing.T, dir string) {
	if err := os.Mkdir(dir, 0777); err != nil {
	t.Fatal(err)
	}
	}

	func chdir(t *testing.T, dir string) {
	if err := os.Chdir(dir); err != nil {
	t.Fatal(err)
	}
	}

	func write(t *testing.T, file, data string) {
	if err := ioutil.WriteFile(file, []byte(data), 0666); err != nil {
	t.Fatal(err)
	}
	}

	func read(t *testing.T, file string) []byte {
	b, err := ioutil.ReadFile(file)
	if err != nil {
	t.Fatal(err)
	}
	return b
	}

	func remove(t *testing.T, file string) {
	if err := os.RemoveAll(file); err != nil {
	t.Fatal(err)
	}
	}

	func trun(t *testing.T, dir string, cmdline ...string) string {
	cmd := exec.Command(cmdline[0], cmdline[1:]...)
	cmd.Dir = dir
	out, err := cmd.CombinedOutput()
	if err != nil {
	if cmdline[0] == "git" {
	t.Fatalf("in %s/, ran %s with %s:\n%v\n%s", filepath.Base(dir), cmdline, gitversion, err, out)
	}
	t.Fatalf("in %s/, ran %s: %v\n%s", filepath.Base(dir), cmdline, err, out)
	}
	return string(out)
	}

	// fromSlash is like filepath.FromSlash, but it ignores ! at the start of the path
	// and " (staged)" at the end.
	func fromSlash(path string) string {
	if len(path) > 0 && path[0] == '!' {
	return "!" + fromSlash(path[1:])
	}
	if strings.HasSuffix(path, " (staged)") {
	return fromSlash(path[:len(path)-len(" (staged)")]) + " (staged)"
	}
	return filepath.FromSlash(path)
	}

	var (
	runLog []string
	testStderr *bytes.Buffer
	testStdout *bytes.Buffer
	died bool
	)

	var mainCanDie bool

	func testMainDied(t *testing.T, args ...string) {
	mainCanDie = true
	testMain(t, args...)
	if !died {
	t.Fatalf("expected to die, did not\nstdout:\n%sstderr:\n%s", testStdout, testStderr)
	}
	}

	func testMainCanDie(t *testing.T, args ...string) {
	mainCanDie = true
	testMain(t, args...)
	}

	func testMain(t *testing.T, args ...string) {
	*noRun = false
	*verbose = 0
	cachedConfig = nil

	t.Logf("git-codereview %s", strings.Join(args, " "))

	canDie := mainCanDie
	mainCanDie = false // reset for next invocation

	defer func() {
	runLog = runLogTrap
	testStdout = stdoutTrap
	testStderr = stderrTrap

	dieTrap = nil
	runLogTrap = nil
	stdoutTrap = nil
	stderrTrap = nil
	if err := recover(); err != nil {
	if died && canDie {
	return
	}
	var msg string
	if died {
	msg = "died"
	} else {
	msg = fmt.Sprintf("panic: %v", err)
	}
	t.Fatalf("%s\nstdout:\n%sstderr:\n%s", msg, testStdout, testStderr)
	}
	}()

	dieTrap = func() {
	died = true
	panic("died")
	}
	died = false
	runLogTrap = []string{} // non-nil, to trigger saving of commands
	stdoutTrap = new(bytes.Buffer)
	stderrTrap = new(bytes.Buffer)

	os.Args = append([]string{"git-codereview"}, args...)
	main()
	}

	func testRan(t *testing.T, cmds ...string) {
	if cmds == nil {
	cmds = []string{}
	}
	if !reflect.DeepEqual(runLog, cmds) {
	t.Errorf("ran:\n%s", strings.Join(runLog, "\n"))
	t.Errorf("wanted:\n%s", strings.Join(cmds, "\n"))
	}
	}

	func testPrinted(t testing.T, buf bytes.Buffer, name string, messages ...string) {
	all := buf.String()
	var errors bytes.Buffer
	for _, msg := range messages {
	if strings.HasPrefix(msg, "!") {
	if strings.Contains(all, msg[1:]) {
	fmt.Fprintf(&errors, "%s does (but should not) contain %q\n", name, msg[1:])
	}
	continue
	}
	if !strings.Contains(all, msg) {
	fmt.Fprintf(&errors, "%s does not contain %q\n", name, msg)
	}
	}
	if errors.Len() > 0 {
	t.Fatalf("wrong output\n%s%s:\n%s", &errors, name, all)
	}
	}

	func testPrintedStdout(t *testing.T, messages ...string) {
	testPrinted(t, testStdout, "stdout", messages...)
	}

	func testPrintedStderr(t *testing.T, messages ...string) {
	testPrinted(t, testStderr, "stderr", messages...)
	}

	func testNoStdout(t *testing.T) {
	if testStdout.Len() != 0 {
	t.Fatalf("unexpected stdout:\n%s", testStdout)
	}
	}

	func testNoStderr(t *testing.T) {
	if testStderr.Len() != 0 {
	t.Fatalf("unexpected stderr:\n%s", testStderr)
	}
	}

	type gerritServer struct {
	l net.Listener
	mu sync.Mutex
	reply map[string]gerritReply
	}

	func newGerritServer(t testing.T) gerritServer {
	l, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
	t.Fatalf("starting fake gerrit: %v", err)
	}

	auth.host = l.Addr().String()
	auth.url = "http://" + auth.host
	auth.project = "proj"
	auth.user = "gopher"
	auth.password = "PASSWORD"

	s := &gerritServer{l: l, reply: make(map[string]gerritReply)}
	go http.Serve(l, s)
	return s
	}

	func (s *gerritServer) done() {
	s.l.Close()
	auth.host = ""
	auth.url = ""
	auth.project = ""
	auth.user = ""
	auth.password = ""
	}

	type gerritReply struct {
	status int
	body string
	json interface{}
	f func() gerritReply
	}

	func (s *gerritServer) setReply(path string, reply gerritReply) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.reply[path] = reply
	}

	func (s *gerritServer) setJSON(id, json string) {
	s.setReply("/a/changes/proj~master~"+id, gerritReply{body: ")]}'\n" + json})
	}

	func (s gerritServer) ServeHTTP(w http.ResponseWriter, req http.Request) {
	s.mu.Lock()
	defer s.mu.Unlock()
	reply, ok := s.reply[req.URL.Path]
	if !ok {
	http.NotFound(w, req)
	return
	}
	if reply.f != nil {
	reply = reply.f()
	}
	if reply.status != 0 {
	w.WriteHeader(reply.status)
	}
	if reply.json != nil {
	body, err := json.Marshal(reply.json)
	if err != nil {
	dief("%v", err)
	}
	reply.body = ")]}'\n" + string(body)
	}
	if len(reply.body) > 0 {
	w.Write([]byte(reply.body))
	}
	}