message/pipeline: copy over files from cmd/gotext
Most of the code will be turned into a package.
Change-Id: I47609e5afb176e42d3b0b29bfa04cca23ab6867f
Reviewed-on: https://go-review.googlesource.com/82235
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>
diff --git a/message/pipeline/common.go b/message/pipeline/common.go
new file mode 100644
index 0000000..ae87e44
--- /dev/null
+++ b/message/pipeline/common.go
@@ -0,0 +1,48 @@
+// Copyright 2017 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 (
+ "fmt"
+ "go/build"
+ "go/parser"
+
+ "golang.org/x/tools/go/loader"
+)
+
+const (
+ extractFile = "extracted.gotext.json"
+ outFile = "out.gotext.json"
+ gotextSuffix = ".gotext.json"
+)
+
+// NOTE: The command line tool already prefixes with "gotext:".
+var (
+ wrap = func(err error, msg string) error {
+ return fmt.Errorf("%s: %v", msg, err)
+ }
+ wrapf = func(err error, msg string, args ...interface{}) error {
+ return wrap(err, fmt.Sprintf(msg, args...))
+ }
+ errorf = fmt.Errorf
+)
+
+func loadPackages(conf *loader.Config, args []string) (*loader.Program, error) {
+ if len(args) == 0 {
+ args = []string{"."}
+ }
+
+ conf.Build = &build.Default
+ conf.ParserMode = parser.ParseComments
+
+ // Use the initial packages from the command line.
+ args, err := conf.FromArgs(args, false)
+ if err != nil {
+ return nil, wrap(err, "loading packages failed")
+ }
+
+ // Load, parse and type-check the whole program.
+ return conf.Load()
+}
diff --git a/message/pipeline/doc.go b/message/pipeline/doc.go
new file mode 100644
index 0000000..2a274f7
--- /dev/null
+++ b/message/pipeline/doc.go
@@ -0,0 +1,53 @@
+// Code generated by go generate. DO NOT EDIT.
+
+// gotext is a tool for managing text in Go source code.
+//
+// Usage:
+//
+// gotext command [arguments]
+//
+// The commands are:
+//
+// extract extracts strings to be translated from code
+// rewrite rewrites fmt functions to use a message Printer
+// generate generates code to insert translated messages
+//
+// Use "go help [command]" for more information about a command.
+//
+// Additional help topics:
+//
+//
+// Use "gotext help [topic]" for more information about that topic.
+//
+//
+// Extracts strings to be translated from code
+//
+// Usage:
+//
+// go extract <package>*
+//
+//
+//
+//
+// Rewrites fmt functions to use a message Printer
+//
+// Usage:
+//
+// go rewrite <package>
+//
+// rewrite is typically done once for a project. It rewrites all usages of
+// fmt to use x/text's message package whenever a message.Printer is in scope.
+// It rewrites Print and Println calls with constant strings to the equivalent
+// using Printf to allow translators to reorder arguments.
+//
+//
+// Generates code to insert translated messages
+//
+// Usage:
+//
+// go generate <package>
+//
+//
+//
+//
+package main
diff --git a/message/pipeline/extract.go b/message/pipeline/extract.go
new file mode 100644
index 0000000..561f050
--- /dev/null
+++ b/message/pipeline/extract.go
@@ -0,0 +1,358 @@
+// Copyright 2016 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"
+ "go/ast"
+ "go/constant"
+ "go/format"
+ "go/token"
+ "go/types"
+ "io/ioutil"
+ "os"
+ "path"
+ "path/filepath"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+
+ "golang.org/x/text/internal"
+ fmtparser "golang.org/x/text/internal/format"
+ "golang.org/x/text/language"
+ "golang.org/x/tools/go/loader"
+)
+
+// TODO:
+// - merge information into existing files
+// - handle different file formats (PO, XLIFF)
+// - handle features (gender, plural)
+// - message rewriting
+
+var (
+ srcLang *string
+ lang *string
+)
+
+func init() {
+ srcLang = cmdExtract.Flag.String("srclang", "en-US", "the source-code language")
+ lang = cmdExtract.Flag.String("lang", "en-US", "comma-separated list of languages to process")
+}
+
+var cmdExtract = &Command{
+ Run: runExtract,
+ UsageLine: "extract <package>*",
+ Short: "extracts strings to be translated from code",
+}
+
+func runExtract(cmd *Command, args []string) error {
+ conf := loader.Config{}
+ prog, err := loadPackages(&conf, args)
+ if err != nil {
+ return wrap(err, "")
+ }
+
+ // print returns Go syntax for the specified node.
+ print := func(n ast.Node) string {
+ var buf bytes.Buffer
+ format.Node(&buf, conf.Fset, n)
+ return buf.String()
+ }
+
+ var messages []Message
+
+ for _, info := range prog.AllPackages {
+ for _, f := range info.Files {
+ // Associate comments with nodes.
+ cmap := ast.NewCommentMap(prog.Fset, f, f.Comments)
+ getComment := func(n ast.Node) string {
+ cs := cmap.Filter(n).Comments()
+ if len(cs) > 0 {
+ return strings.TrimSpace(cs[0].Text())
+ }
+ return ""
+ }
+
+ // Find function calls.
+ ast.Inspect(f, func(n ast.Node) bool {
+ call, ok := n.(*ast.CallExpr)
+ if !ok {
+ return true
+ }
+
+ // Skip calls of functions other than
+ // (*message.Printer).{Sp,Fp,P}rintf.
+ sel, ok := call.Fun.(*ast.SelectorExpr)
+ if !ok {
+ return true
+ }
+ meth := info.Selections[sel]
+ if meth == nil || meth.Kind() != types.MethodVal {
+ return true
+ }
+ // TODO: remove cheap hack and check if the type either
+ // implements some interface or is specifically of type
+ // "golang.org/x/text/message".Printer.
+ m, ok := extractFuncs[path.Base(meth.Recv().String())]
+ if !ok {
+ return true
+ }
+
+ fmtType, ok := m[meth.Obj().Name()]
+ if !ok {
+ return true
+ }
+ // argn is the index of the format string.
+ argn := fmtType.arg
+ if argn >= len(call.Args) {
+ return true
+ }
+
+ args := call.Args[fmtType.arg:]
+
+ fmtMsg, ok := msgStr(info, args[0])
+ if !ok {
+ // TODO: identify the type of the format argument. If it
+ // is not a string, multiple keys may be defined.
+ return true
+ }
+ comment := ""
+ key := []string{}
+ if ident, ok := args[0].(*ast.Ident); ok {
+ key = append(key, ident.Name)
+ if v, ok := ident.Obj.Decl.(*ast.ValueSpec); ok && v.Comment != nil {
+ // TODO: get comment above ValueSpec as well
+ comment = v.Comment.Text()
+ }
+ }
+
+ arguments := []argument{}
+ args = args[1:]
+ simArgs := make([]interface{}, len(args))
+ for i, arg := range args {
+ expr := print(arg)
+ val := ""
+ if v := info.Types[arg].Value; v != nil {
+ val = v.ExactString()
+ simArgs[i] = val
+ switch arg.(type) {
+ case *ast.BinaryExpr, *ast.UnaryExpr:
+ expr = val
+ }
+ }
+ arguments = append(arguments, argument{
+ ArgNum: i + 1,
+ Type: info.Types[arg].Type.String(),
+ UnderlyingType: info.Types[arg].Type.Underlying().String(),
+ Expr: expr,
+ Value: val,
+ Comment: getComment(arg),
+ Position: posString(conf, info, arg.Pos()),
+ // TODO report whether it implements
+ // interfaces plural.Interface,
+ // gender.Interface.
+ })
+ }
+ msg := ""
+
+ ph := placeholders{index: map[string]string{}}
+
+ p := fmtparser.Parser{}
+ p.Reset(simArgs)
+ for p.SetFormat(fmtMsg); p.Scan(); {
+ switch p.Status {
+ case fmtparser.StatusText:
+ msg += p.Text()
+ case fmtparser.StatusSubstitution,
+ fmtparser.StatusBadWidthSubstitution,
+ fmtparser.StatusBadPrecSubstitution:
+ arguments[p.ArgNum-1].used = true
+ arg := arguments[p.ArgNum-1]
+ sub := p.Text()
+ if !p.HasIndex {
+ r, sz := utf8.DecodeLastRuneInString(sub)
+ sub = fmt.Sprintf("%s[%d]%c", sub[:len(sub)-sz], p.ArgNum, r)
+ }
+ msg += fmt.Sprintf("{%s}", ph.addArg(&arg, sub))
+ }
+ }
+ key = append(key, msg)
+
+ // Add additional Placeholders that can be used in translations
+ // that are not present in the string.
+ for _, arg := range arguments {
+ if arg.used {
+ continue
+ }
+ ph.addArg(&arg, fmt.Sprintf("%%[%d]v", arg.ArgNum))
+ }
+
+ if c := getComment(call.Args[0]); c != "" {
+ comment = c
+ }
+
+ messages = append(messages, Message{
+ ID: key,
+ Key: fmtMsg,
+ Message: Text{Msg: msg},
+ // TODO(fix): this doesn't get the before comment.
+ Comment: comment,
+ Placeholders: ph.slice,
+ Position: posString(conf, info, call.Lparen),
+ })
+ return true
+ })
+ }
+ }
+
+ tag, err := language.Parse(*srcLang)
+ if err != nil {
+ return wrap(err, "")
+ }
+ out := Locale{
+ Language: tag,
+ Messages: messages,
+ }
+ data, err := json.MarshalIndent(out, "", " ")
+ if err != nil {
+ return wrap(err, "")
+ }
+ os.MkdirAll(*dir, 0755)
+ // TODO: this file can probably go if we replace the extract + generate
+ // cycle with a init once and update cycle.
+ file := filepath.Join(*dir, extractFile)
+ if err := ioutil.WriteFile(file, data, 0644); err != nil {
+ return wrapf(err, "could not create file")
+ }
+
+ langs := append(getLangs(), tag)
+ langs = internal.UniqueTags(langs)
+ for _, tag := range langs {
+ // TODO: inject translations from existing files to avoid retranslation.
+ out.Language = tag
+ data, err := json.MarshalIndent(out, "", " ")
+ if err != nil {
+ return wrap(err, "JSON marshal failed")
+ }
+ file := filepath.Join(*dir, tag.String(), outFile)
+ if err := os.MkdirAll(filepath.Dir(file), 0750); err != nil {
+ return wrap(err, "dir create failed")
+ }
+ if err := ioutil.WriteFile(file, data, 0740); err != nil {
+ return wrap(err, "write failed")
+ }
+ }
+ return nil
+}
+
+func posString(conf loader.Config, info *loader.PackageInfo, pos token.Pos) string {
+ p := conf.Fset.Position(pos)
+ file := fmt.Sprintf("%s:%d:%d", filepath.Base(p.Filename), p.Line, p.Column)
+ return filepath.Join(info.Pkg.Path(), file)
+}
+
+// extractFuncs indicates the types and methods for which to extract strings,
+// and which argument to extract.
+// TODO: use the types in conf.Import("golang.org/x/text/message") to extract
+// the correct instances.
+var extractFuncs = map[string]map[string]extractType{
+ // TODO: Printer -> *golang.org/x/text/message.Printer
+ "message.Printer": {
+ "Printf": extractType{arg: 0, format: true},
+ "Sprintf": extractType{arg: 0, format: true},
+ "Fprintf": extractType{arg: 1, format: true},
+
+ "Lookup": extractType{arg: 0},
+ },
+}
+
+type extractType struct {
+ // format indicates if the next arg is a formatted string or whether to
+ // concatenate all arguments
+ format bool
+ // arg indicates the position of the argument to extract.
+ arg int
+}
+
+func getID(arg *argument) string {
+ s := getLastComponent(arg.Expr)
+ s = strip(s)
+ s = strings.Replace(s, " ", "", -1)
+ // For small variable names, use user-defined types for more info.
+ if len(s) <= 2 && arg.UnderlyingType != arg.Type {
+ s = getLastComponent(arg.Type)
+ }
+ return strings.Title(s)
+}
+
+// strip is a dirty hack to convert function calls to placeholder IDs.
+func strip(s string) string {
+ s = strings.Map(func(r rune) rune {
+ if unicode.IsSpace(r) || r == '-' {
+ return '_'
+ }
+ if !unicode.In(r, unicode.Letter, unicode.Mark) {
+ return -1
+ }
+ return r
+ }, s)
+ // Strip "Get" from getter functions.
+ if strings.HasPrefix(s, "Get") || strings.HasPrefix(s, "get") {
+ if len(s) > len("get") {
+ r, _ := utf8.DecodeRuneInString(s)
+ if !unicode.In(r, unicode.Ll, unicode.M) { // not lower or mark
+ s = s[len("get"):]
+ }
+ }
+ }
+ return s
+}
+
+type placeholders struct {
+ index map[string]string
+ slice []Placeholder
+}
+
+func (p *placeholders) addArg(arg *argument, sub string) (id string) {
+ id = getID(arg)
+ id1 := id
+ alt, ok := p.index[id1]
+ for i := 1; ok && alt != sub; i++ {
+ id1 = fmt.Sprintf("%s_%d", id, i)
+ alt, ok = p.index[id1]
+ }
+ p.index[id1] = sub
+ p.slice = append(p.slice, Placeholder{
+ ID: id1,
+ String: sub,
+ Type: arg.Type,
+ UnderlyingType: arg.UnderlyingType,
+ ArgNum: arg.ArgNum,
+ Expr: arg.Expr,
+ Comment: arg.Comment,
+ })
+ return id1
+}
+
+func getLastComponent(s string) string {
+ return s[1+strings.LastIndexByte(s, '.'):]
+}
+
+func msgStr(info *loader.PackageInfo, e ast.Expr) (s string, ok bool) {
+ v := info.Types[e].Value
+ if v == nil || v.Kind() != constant.String {
+ return "", false
+ }
+ s = constant.StringVal(v)
+ // Only record strings with letters.
+ for _, r := range s {
+ if unicode.In(r, unicode.L) {
+ return s, true
+ }
+ }
+ return "", false
+}
diff --git a/message/pipeline/generate.go b/message/pipeline/generate.go
new file mode 100644
index 0000000..0293273
--- /dev/null
+++ b/message/pipeline/generate.go
@@ -0,0 +1,322 @@
+// Copyright 2017 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 (
+ "encoding/json"
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "regexp"
+ "sort"
+ "strings"
+ "text/template"
+
+ "golang.org/x/text/collate"
+ "golang.org/x/text/feature/plural"
+ "golang.org/x/text/internal"
+ "golang.org/x/text/internal/catmsg"
+ "golang.org/x/text/internal/gen"
+ "golang.org/x/text/language"
+ "golang.org/x/tools/go/loader"
+)
+
+func init() {
+ out = cmdGenerate.Flag.String("out", "", "output file to write to")
+}
+
+var (
+ out *string
+)
+
+var cmdGenerate = &Command{
+ Run: runGenerate,
+ UsageLine: "generate <package>",
+ Short: "generates code to insert translated messages",
+}
+
+var transRe = regexp.MustCompile(`messages\.(.*)\.json`)
+
+func runGenerate(cmd *Command, args []string) error {
+ prog, err := loadPackages(&loader.Config{}, args)
+ if err != nil {
+ return wrap(err, "could not load package")
+ }
+
+ pkgs := prog.InitialPackages()
+ if len(pkgs) != 1 {
+ return fmt.Errorf("more than one package selected: %v", pkgs)
+ }
+
+ // TODO: add in external input. Right now we assume that all files are
+ // manually created and stored in the textdata directory.
+
+ // Build up index of translations and original messages.
+ extracted := Locale{}
+ translations := map[language.Tag]map[string]Message{}
+ languages := []language.Tag{}
+ langVars := []string{}
+ usedKeys := map[string]int{}
+
+ err = filepath.Walk(*dir, func(path string, f os.FileInfo, err error) error {
+ if err != nil {
+ return wrap(err, "loading data")
+ }
+ if f.IsDir() {
+ return nil
+ }
+ if f.Name() == extractFile {
+ b, err := ioutil.ReadFile(path)
+ if err != nil {
+ return wrap(err, "read file failed")
+ }
+ if err := json.Unmarshal(b, &extracted); err != nil {
+ return wrap(err, "unmarshal source failed")
+ }
+ return nil
+ }
+ if f.Name() == outFile {
+ return nil
+ }
+ if !strings.HasSuffix(path, gotextSuffix) {
+ return nil
+ }
+ b, err := ioutil.ReadFile(path)
+ if err != nil {
+ return wrap(err, "read file failed")
+ }
+ var locale Locale
+ if err := json.Unmarshal(b, &locale); err != nil {
+ return wrap(err, "parsing translation file failed")
+ }
+ tag := locale.Language
+ if _, ok := translations[tag]; !ok {
+ translations[tag] = map[string]Message{}
+ languages = append(languages, tag)
+ }
+ for _, m := range locale.Messages {
+ if !m.Translation.IsEmpty() {
+ for _, id := range m.ID {
+ if _, ok := translations[tag][id]; ok {
+ logf("Duplicate translation in locale %q for message %q", tag, id)
+ }
+ translations[tag][id] = m
+ }
+ }
+ }
+ return nil
+ })
+ if err != nil {
+ return err
+ }
+
+ // Verify completeness and register keys.
+ internal.SortTags(languages)
+
+ for _, tag := range languages {
+ langVars = append(langVars, strings.Replace(tag.String(), "-", "_", -1))
+ dict := translations[tag]
+ for _, msg := range extracted.Messages {
+ for _, id := range msg.ID {
+ if trans, ok := dict[id]; ok && !trans.Translation.IsEmpty() {
+ if _, ok := usedKeys[msg.Key]; !ok {
+ usedKeys[msg.Key] = len(usedKeys)
+ }
+ break
+ }
+ // TODO: log missing entry.
+ logf("%s: Missing entry for %q.", tag, id)
+ }
+ }
+ }
+
+ w := gen.NewCodeWriter()
+
+ x := &struct {
+ Fallback language.Tag
+ Languages []string
+ }{
+ Fallback: extracted.Language,
+ Languages: langVars,
+ }
+
+ if err := lookup.Execute(w, x); err != nil {
+ return wrap(err, "error")
+ }
+
+ keyToIndex := []string{}
+ for k := range usedKeys {
+ keyToIndex = append(keyToIndex, k)
+ }
+ sort.Strings(keyToIndex)
+ fmt.Fprint(w, "var messageKeyToIndex = map[string]int{\n")
+ for _, k := range keyToIndex {
+ fmt.Fprintf(w, "%q: %d,\n", k, usedKeys[k])
+ }
+ fmt.Fprint(w, "}\n\n")
+
+ for i, tag := range languages {
+ dict := translations[tag]
+ a := make([]string, len(usedKeys))
+ for _, msg := range extracted.Messages {
+ for _, id := range msg.ID {
+ if trans, ok := dict[id]; ok && !trans.Translation.IsEmpty() {
+ m, err := assemble(&msg, &trans.Translation)
+ if err != nil {
+ return wrap(err, "error")
+ }
+ // TODO: support macros.
+ data, err := catmsg.Compile(tag, nil, m)
+ if err != nil {
+ return wrap(err, "error")
+ }
+ key := usedKeys[msg.Key]
+ if d := a[key]; d != "" && d != data {
+ logf("Duplicate non-consistent translation for key %q, picking the one for message %q", msg.Key, id)
+ }
+ a[key] = string(data)
+ break
+ }
+ }
+ }
+ index := []uint32{0}
+ p := 0
+ for _, s := range a {
+ p += len(s)
+ index = append(index, uint32(p))
+ }
+
+ w.WriteVar(langVars[i]+"Index", index)
+ w.WriteConst(langVars[i]+"Data", strings.Join(a, ""))
+ }
+
+ pkg := pkgs[0].Pkg.Name()
+ if *out == "" {
+ if _, err = w.WriteGo(os.Stdout, pkg); err != nil {
+ return wrap(err, "could not write go file")
+ }
+ } else {
+ w.WriteGoFile(*out, pkg)
+ }
+
+ return nil
+}
+
+func assemble(m *Message, t *Text) (msg catmsg.Message, err error) {
+ keys := []string{}
+ for k := range t.Var {
+ keys = append(keys, k)
+ }
+ sort.Strings(keys)
+ var a []catmsg.Message
+ for _, k := range keys {
+ t := t.Var[k]
+ m, err := assemble(m, &t)
+ if err != nil {
+ return nil, err
+ }
+ a = append(a, &catmsg.Var{Name: k, Message: m})
+ }
+ if t.Select != nil {
+ s, err := assembleSelect(m, t.Select)
+ if err != nil {
+ return nil, err
+ }
+ a = append(a, s)
+ }
+ if t.Msg != "" {
+ sub, err := m.Substitute(t.Msg)
+ if err != nil {
+ return nil, err
+ }
+ a = append(a, catmsg.String(sub))
+ }
+ switch len(a) {
+ case 0:
+ return nil, errorf("generate: empty message")
+ case 1:
+ return a[0], nil
+ default:
+ return catmsg.FirstOf(a), nil
+
+ }
+}
+
+func assembleSelect(m *Message, s *Select) (msg catmsg.Message, err error) {
+ cases := []string{}
+ for c := range s.Cases {
+ cases = append(cases, c)
+ }
+ sortCases(cases)
+
+ caseMsg := []interface{}{}
+ for _, c := range cases {
+ cm := s.Cases[c]
+ m, err := assemble(m, &cm)
+ if err != nil {
+ return nil, err
+ }
+ caseMsg = append(caseMsg, c, m)
+ }
+
+ ph := m.Placeholder(s.Arg)
+
+ switch s.Feature {
+ case "plural":
+ // TODO: only printf-style selects are supported as of yet.
+ return plural.Selectf(ph.ArgNum, ph.String, caseMsg...), nil
+ }
+ return nil, errorf("unknown feature type %q", s.Feature)
+}
+
+func sortCases(cases []string) {
+ // TODO: implement full interface.
+ sort.Slice(cases, func(i, j int) bool {
+ if cases[j] == "other" && cases[i] != "other" {
+ return true
+ }
+ // the following code relies on '<' < '=' < any letter.
+ return cmpNumeric(cases[i], cases[j]) == -1
+ })
+}
+
+var cmpNumeric = collate.New(language.Und, collate.Numeric).CompareString
+
+var lookup = template.Must(template.New("gen").Parse(`
+import (
+ "golang.org/x/text/language"
+ "golang.org/x/text/message"
+ "golang.org/x/text/message/catalog"
+)
+
+type dictionary struct {
+ index []uint32
+ data string
+}
+
+func (d *dictionary) Lookup(key string) (data string, ok bool) {
+ p := messageKeyToIndex[key]
+ start, end := d.index[p], d.index[p+1]
+ if start == end {
+ return "", false
+ }
+ return d.data[start:end], true
+}
+
+func init() {
+ dict := map[string]catalog.Dictionary{
+ {{range .Languages}}"{{.}}": &dictionary{index: {{.}}Index, data: {{.}}Data },
+ {{end}}
+ }
+ fallback := language.MustParse("{{.Fallback}}")
+ cat, err := catalog.NewFromMap(dict, catalog.Fallback(fallback))
+ if err != nil {
+ panic(err)
+ }
+ message.DefaultCatalog = cat
+}
+
+`))
diff --git a/message/pipeline/main.go b/message/pipeline/main.go
new file mode 100644
index 0000000..f3f50d7
--- /dev/null
+++ b/message/pipeline/main.go
@@ -0,0 +1,352 @@
+// Copyright 2016 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:generate go build -o gotext.latest
+//go:generate ./gotext.latest help gendocumentation
+//go:generate rm gotext.latest
+
+package main
+
+import (
+ "bufio"
+ "bytes"
+ "flag"
+ "fmt"
+ "go/build"
+ "go/format"
+ "io"
+ "io/ioutil"
+ "log"
+ "os"
+ "strings"
+ "sync"
+ "text/template"
+ "unicode"
+ "unicode/utf8"
+
+ "golang.org/x/text/language"
+ "golang.org/x/tools/go/buildutil"
+)
+
+func init() {
+ flag.Var((*buildutil.TagsFlag)(&build.Default.BuildTags), "tags", buildutil.TagsFlagDoc)
+}
+
+var dir = flag.String("dir", "locales", "default subdirectory to store translation files")
+
+// NOTE: the Command struct is copied from the go tool in core.
+
+// A Command is an implementation of a go command
+// like go build or go fix.
+type Command struct {
+ // Run runs the command.
+ // The args are the arguments after the command name.
+ Run func(cmd *Command, args []string) error
+
+ // UsageLine is the one-line usage message.
+ // The first word in the line is taken to be the command name.
+ UsageLine string
+
+ // Short is the short description shown in the 'go help' output.
+ Short string
+
+ // Long is the long message shown in the 'go help <this-command>' output.
+ Long string
+
+ // Flag is a set of flags specific to this command.
+ Flag flag.FlagSet
+}
+
+// Name returns the command's name: the first word in the usage line.
+func (c *Command) Name() string {
+ name := c.UsageLine
+ i := strings.Index(name, " ")
+ if i >= 0 {
+ name = name[:i]
+ }
+ return name
+}
+
+func (c *Command) Usage() {
+ fmt.Fprintf(os.Stderr, "usage: %s\n\n", c.UsageLine)
+ fmt.Fprintf(os.Stderr, "%s\n", strings.TrimSpace(c.Long))
+ os.Exit(2)
+}
+
+// Runnable reports whether the command can be run; otherwise
+// it is a documentation pseudo-command such as importpath.
+func (c *Command) Runnable() bool {
+ return c.Run != nil
+}
+
+// Commands lists the available commands and help topics.
+// The order here is the order in which they are printed by 'go help'.
+var commands = []*Command{
+ cmdExtract,
+ cmdRewrite,
+ cmdGenerate,
+ // TODO:
+ // - update: full-cycle update of extraction, sending, and integration
+ // - report: report of freshness of translations
+}
+
+var exitStatus = 0
+var exitMu sync.Mutex
+
+func setExitStatus(n int) {
+ exitMu.Lock()
+ if exitStatus < n {
+ exitStatus = n
+ }
+ exitMu.Unlock()
+}
+
+var origEnv []string
+
+func main() {
+ flag.Usage = usage
+ flag.Parse()
+ log.SetFlags(0)
+
+ args := flag.Args()
+ if len(args) < 1 {
+ usage()
+ }
+
+ if args[0] == "help" {
+ help(args[1:])
+ return
+ }
+
+ for _, cmd := range commands {
+ if cmd.Name() == args[0] && cmd.Runnable() {
+ cmd.Flag.Usage = func() { cmd.Usage() }
+ cmd.Flag.Parse(args[1:])
+ args = cmd.Flag.Args()
+ if err := cmd.Run(cmd, args); err != nil {
+ fatalf("gotext: %+v", err)
+ }
+ exit()
+ return
+ }
+ }
+
+ fmt.Fprintf(os.Stderr, "gotext: unknown subcommand %q\nRun 'go help' for usage.\n", args[0])
+ setExitStatus(2)
+ exit()
+}
+
+var usageTemplate = `gotext is a tool for managing text in Go source code.
+
+Usage:
+
+ gotext command [arguments]
+
+The commands are:
+{{range .}}{{if .Runnable}}
+ {{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
+
+Use "go help [command]" for more information about a command.
+
+Additional help topics:
+{{range .}}{{if not .Runnable}}
+ {{.Name | printf "%-11s"}} {{.Short}}{{end}}{{end}}
+
+Use "gotext help [topic]" for more information about that topic.
+
+`
+
+var helpTemplate = `{{if .Runnable}}usage: go {{.UsageLine}}
+
+{{end}}{{.Long | trim}}
+`
+
+var documentationTemplate = `{{range .}}{{if .Short}}{{.Short | capitalize}}
+
+{{end}}{{if .Runnable}}Usage:
+
+ go {{.UsageLine}}
+
+{{end}}{{.Long | trim}}
+
+
+{{end}}`
+
+// commentWriter writes a Go comment to the underlying io.Writer,
+// using line comment form (//).
+type commentWriter struct {
+ W io.Writer
+ wroteSlashes bool // Wrote "//" at the beginning of the current line.
+}
+
+func (c *commentWriter) Write(p []byte) (int, error) {
+ var n int
+ for i, b := range p {
+ if !c.wroteSlashes {
+ s := "//"
+ if b != '\n' {
+ s = "// "
+ }
+ if _, err := io.WriteString(c.W, s); err != nil {
+ return n, err
+ }
+ c.wroteSlashes = true
+ }
+ n0, err := c.W.Write(p[i : i+1])
+ n += n0
+ if err != nil {
+ return n, err
+ }
+ if b == '\n' {
+ c.wroteSlashes = false
+ }
+ }
+ return len(p), nil
+}
+
+// An errWriter wraps a writer, recording whether a write error occurred.
+type errWriter struct {
+ w io.Writer
+ err error
+}
+
+func (w *errWriter) Write(b []byte) (int, error) {
+ n, err := w.w.Write(b)
+ if err != nil {
+ w.err = err
+ }
+ return n, err
+}
+
+// tmpl executes the given template text on data, writing the result to w.
+func tmpl(w io.Writer, text string, data interface{}) {
+ t := template.New("top")
+ t.Funcs(template.FuncMap{"trim": strings.TrimSpace, "capitalize": capitalize})
+ template.Must(t.Parse(text))
+ ew := &errWriter{w: w}
+ err := t.Execute(ew, data)
+ if ew.err != nil {
+ // I/O error writing. Ignore write on closed pipe.
+ if strings.Contains(ew.err.Error(), "pipe") {
+ os.Exit(1)
+ }
+ fatalf("writing output: %v", ew.err)
+ }
+ if err != nil {
+ panic(err)
+ }
+}
+
+func capitalize(s string) string {
+ if s == "" {
+ return s
+ }
+ r, n := utf8.DecodeRuneInString(s)
+ return string(unicode.ToTitle(r)) + s[n:]
+}
+
+func printUsage(w io.Writer) {
+ bw := bufio.NewWriter(w)
+ tmpl(bw, usageTemplate, commands)
+ bw.Flush()
+}
+
+func usage() {
+ printUsage(os.Stderr)
+ os.Exit(2)
+}
+
+// help implements the 'help' command.
+func help(args []string) {
+ if len(args) == 0 {
+ printUsage(os.Stdout)
+ // not exit 2: succeeded at 'go help'.
+ return
+ }
+ if len(args) != 1 {
+ fmt.Fprintf(os.Stderr, "usage: go help command\n\nToo many arguments given.\n")
+ os.Exit(2) // failed at 'go help'
+ }
+
+ arg := args[0]
+
+ // 'go help documentation' generates doc.go.
+ if strings.HasSuffix(arg, "documentation") {
+ w := &bytes.Buffer{}
+
+ fmt.Fprintln(w, "// Code generated by go generate. DO NOT EDIT.")
+ fmt.Fprintln(w)
+ buf := new(bytes.Buffer)
+ printUsage(buf)
+ usage := &Command{Long: buf.String()}
+ tmpl(&commentWriter{W: w}, documentationTemplate, append([]*Command{usage}, commands...))
+ fmt.Fprintln(w, "package main")
+ if arg == "gendocumentation" {
+ b, err := format.Source(w.Bytes())
+ if err != nil {
+ logf("Could not format generated docs: %v\n", err)
+ }
+ if err := ioutil.WriteFile("doc.go", b, 0666); err != nil {
+ logf("Could not create file alldocs.go: %v\n", err)
+ }
+ } else {
+ fmt.Println(w.String())
+ }
+ return
+ }
+
+ for _, cmd := range commands {
+ if cmd.Name() == arg {
+ tmpl(os.Stdout, helpTemplate, cmd)
+ // not exit 2: succeeded at 'go help cmd'.
+ return
+ }
+ }
+
+ fmt.Fprintf(os.Stderr, "Unknown help topic %#q. Run 'go help'.\n", arg)
+ os.Exit(2) // failed at 'go help cmd'
+}
+
+func getLangs() (tags []language.Tag) {
+ for _, t := range strings.Split(*lang, ",") {
+ if t == "" {
+ continue
+ }
+ tag, err := language.Parse(t)
+ if err != nil {
+ fatalf("gotext: could not parse language %q: %v", t, err)
+ }
+ tags = append(tags, tag)
+ }
+ return tags
+}
+
+var atexitFuncs []func()
+
+func atexit(f func()) {
+ atexitFuncs = append(atexitFuncs, f)
+}
+
+func exit() {
+ for _, f := range atexitFuncs {
+ f()
+ }
+ os.Exit(exitStatus)
+}
+
+func fatalf(format string, args ...interface{}) {
+ logf(format, args...)
+ exit()
+}
+
+func logf(format string, args ...interface{}) {
+ log.Printf(format, args...)
+ setExitStatus(1)
+}
+
+func exitIfErrors() {
+ if exitStatus != 0 {
+ exit()
+ }
+}
diff --git a/message/pipeline/message.go b/message/pipeline/message.go
new file mode 100644
index 0000000..990ba52
--- /dev/null
+++ b/message/pipeline/message.go
@@ -0,0 +1,222 @@
+// Copyright 2016 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 (
+ "encoding/json"
+ "strings"
+
+ "golang.org/x/text/language"
+)
+
+// TODO: these definitions should be moved to a package so that the can be used
+// by other tools.
+
+// The file contains the structures used to define translations of a certain
+// messages.
+//
+// A translation may have multiple translations strings, or messages, depending
+// on the feature values of the various arguments. For instance, consider
+// a hypothetical translation from English to English, where the source defines
+// the format string "%d file(s) remaining".
+// See the examples directory for examples of extracted messages.
+
+// A Locale is used to store all information for a single locale. This type is
+// used both for extraction and injection.
+type Locale struct {
+ Language language.Tag `json:"language"`
+ Messages []Message `json:"messages"`
+ Macros map[string]Text `json:"macros,omitempty"`
+}
+
+// A Message describes a message to be translated.
+type Message struct {
+ // ID contains a list of identifiers for the message.
+ ID IDList `json:"id"`
+ // Key is the string that is used to look up the message at runtime.
+ Key string `json:"key"`
+ Meaning string `json:"meaning,omitempty"`
+ Message Text `json:"message"`
+ Translation Text `json:"translation"`
+
+ Comment string `json:"comment,omitempty"`
+ TranslatorComment string `json:"translatorComment,omitempty"`
+
+ Placeholders []Placeholder `json:"placeholders,omitempty"`
+
+ // TODO: default placeholder syntax is {foo}. Allow alternative escaping
+ // like `foo`.
+
+ // Extraction information.
+ Position string `json:"position,omitempty"` // filePosition:line
+}
+
+// Placeholder reports the placeholder for the given ID if it is defined or nil
+// otherwise.
+func (m *Message) Placeholder(id string) *Placeholder {
+ for _, p := range m.Placeholders {
+ if p.ID == id {
+ return &p
+ }
+ }
+ return nil
+}
+
+// Substitute replaces placeholders in msg with their original value.
+func (m *Message) Substitute(msg string) (sub string, err error) {
+ last := 0
+ for i := 0; i < len(msg); {
+ pLeft := strings.IndexByte(msg[i:], '{')
+ if pLeft == -1 {
+ break
+ }
+ pLeft += i
+ pRight := strings.IndexByte(msg[pLeft:], '}')
+ if pRight == -1 {
+ return "", errorf("unmatched '}'")
+ }
+ pRight += pLeft
+ id := strings.TrimSpace(msg[pLeft+1 : pRight])
+ i = pRight + 1
+ if id != "" && id[0] == '$' {
+ continue
+ }
+ sub += msg[last:pLeft]
+ last = i
+ ph := m.Placeholder(id)
+ if ph == nil {
+ return "", errorf("unknown placeholder %q in message %q", id, msg)
+ }
+ sub += ph.String
+ }
+ sub += msg[last:]
+ return sub, err
+}
+
+// A Placeholder is a part of the message that should not be changed by a
+// translator. It can be used to hide or prettify format strings (e.g. %d or
+// {{.Count}}), hide HTML, or mark common names that should not be translated.
+type Placeholder struct {
+ // ID is the placeholder identifier without the curly braces.
+ ID string `json:"id"`
+
+ // String is the string with which to replace the placeholder. This may be a
+ // formatting string (for instance "%d" or "{{.Count}}") or a literal string
+ // (<div>).
+ String string `json:"string"`
+
+ Type string `json:"type"`
+ UnderlyingType string `json:"underlyingType"`
+ // ArgNum and Expr are set if the placeholder is a substitution of an
+ // argument.
+ ArgNum int `json:"argNum,omitempty"`
+ Expr string `json:"expr,omitempty"`
+
+ Comment string `json:"comment,omitempty"`
+ Example string `json:"example,omitempty"`
+
+ // Features contains the features that are available for the implementation
+ // of this argument.
+ Features []Feature `json:"features,omitempty"`
+}
+
+// An argument contains information about the arguments passed to a message.
+type argument struct {
+ // ArgNum corresponds to the number that should be used for explicit argument indexes (e.g.
+ // "%[1]d").
+ ArgNum int `json:"argNum,omitempty"`
+
+ used bool // Used by Placeholder
+ Type string `json:"type"`
+ UnderlyingType string `json:"underlyingType"`
+ Expr string `json:"expr"`
+ Value string `json:"value,omitempty"`
+ Comment string `json:"comment,omitempty"`
+ Position string `json:"position,omitempty"`
+}
+
+// Feature holds information about a feature that can be implemented by
+// an Argument.
+type Feature struct {
+ Type string `json:"type"` // Right now this is only gender and plural.
+
+ // TODO: possible values and examples for the language under consideration.
+
+}
+
+// Text defines a message to be displayed.
+type Text struct {
+ // Msg and Select contains the message to be displayed. Msg may be used as
+ // a fallback value if none of the select cases match.
+ Msg string `json:"msg,omitempty"`
+ Select *Select `json:"select,omitempty"`
+
+ // Var defines a map of variables that may be substituted in the selected
+ // message.
+ Var map[string]Text `json:"var,omitempty"`
+
+ // Example contains an example message formatted with default values.
+ Example string `json:"example,omitempty"`
+}
+
+// IsEmpty reports whether this Text can generate anything.
+func (t *Text) IsEmpty() bool {
+ return t.Msg == "" && t.Select == nil && t.Var == nil
+}
+
+// rawText erases the UnmarshalJSON method.
+type rawText Text
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (t *Text) UnmarshalJSON(b []byte) error {
+ if b[0] == '"' {
+ return json.Unmarshal(b, &t.Msg)
+ }
+ return json.Unmarshal(b, (*rawText)(t))
+}
+
+// MarshalJSON implements json.Marshaler.
+func (t *Text) MarshalJSON() ([]byte, error) {
+ if t.Select == nil && t.Var == nil && t.Example == "" {
+ return json.Marshal(t.Msg)
+ }
+ return json.Marshal((*rawText)(t))
+}
+
+// IDList is a set identifiers that each may refer to possibly different
+// versions of the same message. When looking up a messages, the first
+// identifier in the list takes precedence.
+type IDList []string
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (id *IDList) UnmarshalJSON(b []byte) error {
+ if b[0] == '"' {
+ *id = []string{""}
+ return json.Unmarshal(b, &((*id)[0]))
+ }
+ return json.Unmarshal(b, (*[]string)(id))
+}
+
+// MarshalJSON implements json.Marshaler.
+func (id *IDList) MarshalJSON() ([]byte, error) {
+ if len(*id) == 1 {
+ return json.Marshal((*id)[0])
+ }
+ return json.Marshal((*[]string)(id))
+}
+
+// Select selects a Text based on the feature value associated with a feature of
+// a certain argument.
+type Select struct {
+ Feature string `json:"feature"` // Name of Feature type (e.g plural)
+ Arg string `json:"arg"` // The placeholder ID
+ Cases map[string]Text `json:"cases"`
+}
+
+// TODO: order matters, but can we derive the ordering from the case keys?
+// type Case struct {
+// Key string `json:"key"`
+// Value Text `json:"value"`
+// }
diff --git a/message/pipeline/rewrite.go b/message/pipeline/rewrite.go
new file mode 100644
index 0000000..f4641c8
--- /dev/null
+++ b/message/pipeline/rewrite.go
@@ -0,0 +1,287 @@
+// Copyright 2017 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"
+ "fmt"
+ "go/ast"
+ "go/constant"
+ "go/format"
+ "go/token"
+ "os"
+ "strings"
+
+ "golang.org/x/tools/go/loader"
+)
+
+const printerType = "golang.org/x/text/message.Printer"
+
+// TODO:
+// - merge information into existing files
+// - handle different file formats (PO, XLIFF)
+// - handle features (gender, plural)
+// - message rewriting
+
+func init() {
+ overwrite = cmdRewrite.Flag.Bool("w", false, "write files in place")
+}
+
+var (
+ overwrite *bool
+)
+
+var cmdRewrite = &Command{
+ Run: runRewrite,
+ UsageLine: "rewrite <package>",
+ Short: "rewrites fmt functions to use a message Printer",
+ Long: `
+rewrite is typically done once for a project. It rewrites all usages of
+fmt to use x/text's message package whenever a message.Printer is in scope.
+It rewrites Print and Println calls with constant strings to the equivalent
+using Printf to allow translators to reorder arguments.
+`,
+}
+
+func runRewrite(cmd *Command, args []string) error {
+ conf := &loader.Config{
+ AllowErrors: true, // Allow unused instances of message.Printer.
+ }
+ prog, err := loadPackages(conf, args)
+ if err != nil {
+ return wrap(err, "")
+ }
+
+ for _, info := range prog.InitialPackages() {
+ for _, f := range info.Files {
+ // Associate comments with nodes.
+
+ // Pick up initialized Printers at the package level.
+ r := rewriter{info: info, conf: conf}
+ for _, n := range info.InitOrder {
+ if t := r.info.Types[n.Rhs].Type.String(); strings.HasSuffix(t, printerType) {
+ r.printerVar = n.Lhs[0].Name()
+ }
+ }
+
+ ast.Walk(&r, f)
+
+ w := os.Stdout
+ if *overwrite {
+ var err error
+ if w, err = os.Create(conf.Fset.File(f.Pos()).Name()); err != nil {
+ return wrap(err, "open failed")
+ }
+ }
+
+ if err := format.Node(w, conf.Fset, f); err != nil {
+ return wrap(err, "go format failed")
+ }
+ }
+ }
+
+ return nil
+}
+
+type rewriter struct {
+ info *loader.PackageInfo
+ conf *loader.Config
+ printerVar string
+}
+
+// print returns Go syntax for the specified node.
+func (r *rewriter) print(n ast.Node) string {
+ var buf bytes.Buffer
+ format.Node(&buf, r.conf.Fset, n)
+ return buf.String()
+}
+
+func (r *rewriter) Visit(n ast.Node) ast.Visitor {
+ // Save the state by scope.
+ if _, ok := n.(*ast.BlockStmt); ok {
+ r := *r
+ return &r
+ }
+ // Find Printers created by assignment.
+ stmt, ok := n.(*ast.AssignStmt)
+ if ok {
+ for _, v := range stmt.Lhs {
+ if r.printerVar == r.print(v) {
+ r.printerVar = ""
+ }
+ }
+ for i, v := range stmt.Rhs {
+ if t := r.info.Types[v].Type.String(); strings.HasSuffix(t, printerType) {
+ r.printerVar = r.print(stmt.Lhs[i])
+ return r
+ }
+ }
+ }
+ // Find Printers created by variable declaration.
+ spec, ok := n.(*ast.ValueSpec)
+ if ok {
+ for _, v := range spec.Names {
+ if r.printerVar == r.print(v) {
+ r.printerVar = ""
+ }
+ }
+ for i, v := range spec.Values {
+ if t := r.info.Types[v].Type.String(); strings.HasSuffix(t, printerType) {
+ r.printerVar = r.print(spec.Names[i])
+ return r
+ }
+ }
+ }
+ if r.printerVar == "" {
+ return r
+ }
+ call, ok := n.(*ast.CallExpr)
+ if !ok {
+ return r
+ }
+
+ // TODO: Handle literal values?
+ sel, ok := call.Fun.(*ast.SelectorExpr)
+ if !ok {
+ return r
+ }
+ meth := r.info.Selections[sel]
+
+ source := r.print(sel.X)
+ fun := r.print(sel.Sel)
+ if meth != nil {
+ source = meth.Recv().String()
+ fun = meth.Obj().Name()
+ }
+
+ // TODO: remove cheap hack and check if the type either
+ // implements some interface or is specifically of type
+ // "golang.org/x/text/message".Printer.
+ m, ok := rewriteFuncs[source]
+ if !ok {
+ return r
+ }
+
+ rewriteType, ok := m[fun]
+ if !ok {
+ return r
+ }
+ ident := ast.NewIdent(r.printerVar)
+ ident.NamePos = sel.X.Pos()
+ sel.X = ident
+ if rewriteType.method != "" {
+ sel.Sel.Name = rewriteType.method
+ }
+
+ // Analyze arguments.
+ argn := rewriteType.arg
+ if rewriteType.format || argn >= len(call.Args) {
+ return r
+ }
+ hasConst := false
+ for _, a := range call.Args[argn:] {
+ if v := r.info.Types[a].Value; v != nil && v.Kind() == constant.String {
+ hasConst = true
+ break
+ }
+ }
+ if !hasConst {
+ return r
+ }
+ sel.Sel.Name = rewriteType.methodf
+
+ // We are done if there is only a single string that does not need to be
+ // escaped.
+ if len(call.Args) == 1 {
+ s, ok := constStr(r.info, call.Args[0])
+ if ok && !strings.Contains(s, "%") && !rewriteType.newLine {
+ return r
+ }
+ }
+
+ // Rewrite arguments as format string.
+ expr := &ast.BasicLit{
+ ValuePos: call.Lparen,
+ Kind: token.STRING,
+ }
+ newArgs := append(call.Args[:argn:argn], expr)
+ newStr := []string{}
+ for i, a := range call.Args[argn:] {
+ if s, ok := constStr(r.info, a); ok {
+ newStr = append(newStr, strings.Replace(s, "%", "%%", -1))
+ } else {
+ newStr = append(newStr, "%v")
+ newArgs = append(newArgs, call.Args[argn+i])
+ }
+ }
+ s := strings.Join(newStr, rewriteType.sep)
+ if rewriteType.newLine {
+ s += "\n"
+ }
+ expr.Value = fmt.Sprintf("%q", s)
+
+ call.Args = newArgs
+
+ // TODO: consider creating an expression instead of a constant string and
+ // then wrapping it in an escape function or so:
+ // call.Args[argn+i] = &ast.CallExpr{
+ // Fun: &ast.SelectorExpr{
+ // X: ast.NewIdent("message"),
+ // Sel: ast.NewIdent("Lookup"),
+ // },
+ // Args: []ast.Expr{a},
+ // }
+ // }
+
+ return r
+}
+
+type rewriteType struct {
+ // method is the name of the equivalent method on a printer, or "" if it is
+ // the same.
+ method string
+
+ // methodf is the method to use if the arguments can be rewritten as a
+ // arguments to a printf-style call.
+ methodf string
+
+ // format is true if the method takes a formatting string followed by
+ // substitution arguments.
+ format bool
+
+ // arg indicates the position of the argument to extract. If all is
+ // positive, all arguments from this argument onwards needs to be extracted.
+ arg int
+
+ sep string
+ newLine bool
+}
+
+// rewriteFuncs list functions that can be directly mapped to the printer
+// functions of the message package.
+var rewriteFuncs = map[string]map[string]rewriteType{
+ // TODO: Printer -> *golang.org/x/text/message.Printer
+ "fmt": {
+ "Print": rewriteType{methodf: "Printf"},
+ "Sprint": rewriteType{methodf: "Sprintf"},
+ "Fprint": rewriteType{methodf: "Fprintf"},
+
+ "Println": rewriteType{methodf: "Printf", sep: " ", newLine: true},
+ "Sprintln": rewriteType{methodf: "Sprintf", sep: " ", newLine: true},
+ "Fprintln": rewriteType{methodf: "Fprintf", sep: " ", newLine: true},
+
+ "Printf": rewriteType{method: "Printf", format: true},
+ "Sprintf": rewriteType{method: "Sprintf", format: true},
+ "Fprintf": rewriteType{method: "Fprintf", format: true},
+ },
+}
+
+func constStr(info *loader.PackageInfo, e ast.Expr) (s string, ok bool) {
+ v := info.Types[e].Value
+ if v == nil || v.Kind() != constant.String {
+ return "", false
+ }
+ return constant.StringVal(v), true
+}
