Checking in vendor folder for ease of using go get.

vendor/golang.org/x/text/message/catalog.go

@@ -0,0 +1,36 @@
+// Copyright 2015 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 message
+
+// TODO: some types in this file will need to be made public at some time.
+// Documentation and method names will reflect this by using the exported name.
+
+import (
+	"golang.org/x/text/language"
+	"golang.org/x/text/message/catalog"
+)
+
+// MatchLanguage reports the matched tag obtained from language.MatchStrings for
+// the Matcher of the DefaultCatalog.
+func MatchLanguage(preferred ...string) language.Tag {
+	c := DefaultCatalog
+	tag, _ := language.MatchStrings(c.Matcher(), preferred...)
+	return tag
+}
+
+// DefaultCatalog is used by SetString.
+var DefaultCatalog catalog.Catalog = defaultCatalog
+
+var defaultCatalog = catalog.NewBuilder()
+
+// SetString calls SetString on the initial default Catalog.
+func SetString(tag language.Tag, key string, msg string) error {
+	return defaultCatalog.SetString(tag, key, msg)
+}
+
+// Set calls Set on the initial default Catalog.
+func Set(tag language.Tag, key string, msg ...catalog.Message) error {
+	return defaultCatalog.Set(tag, key, msg...)
+}

vendor/golang.org/x/text/message/catalog/catalog.go

@@ -0,0 +1,369 @@
+// 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 catalog defines collections of translated format strings.
+//
+// This package mostly defines types for populating catalogs with messages. The
+// catmsg package contains further definitions for creating custom message and
+// dictionary types as well as packages that use Catalogs.
+//
+// Package catalog defines various interfaces: Dictionary, Loader, and Message.
+// A Dictionary maintains a set of translations of format strings for a single
+// language. The Loader interface defines a source of dictionaries. A
+// translation of a format string is represented by a Message.
+//
+//
+// Catalogs
+//
+// A Catalog defines a programmatic interface for setting message translations.
+// It maintains a set of per-language dictionaries with translations for a set
+// of keys. For message translation to function properly, a translation should
+// be defined for each key for each supported language. A dictionary may be
+// underspecified, though, if there is a parent language that already defines
+// the key. For example, a Dictionary for "en-GB" could leave out entries that
+// are identical to those in a dictionary for "en".
+//
+//
+// Messages
+//
+// A Message is a format string which varies on the value of substitution
+// variables. For instance, to indicate the number of results one could want "no
+// results" if there are none, "1 result" if there is 1, and "%d results" for
+// any other number. Catalog is agnostic to the kind of format strings that are
+// used: for instance, messages can follow either the printf-style substitution
+// from package fmt or use templates.
+//
+// A Message does not substitute arguments in the format string. This job is
+// reserved for packages that render strings, such as message, that use Catalogs
+// to selected string. This separation of concerns allows Catalog to be used to
+// store any kind of formatting strings.
+//
+//
+// Selecting messages based on linguistic features of substitution arguments
+//
+// Messages may vary based on any linguistic features of the argument values.
+// The most common one is plural form, but others exist.
+//
+// Selection messages are provided in packages that provide support for a
+// specific linguistic feature. The following snippet uses plural.Select:
+//
+//   catalog.Set(language.English, "You are %d minute(s) late.",
+//       plural.Select(1,
+//           "one", "You are 1 minute late.",
+//           "other", "You are %d minutes late."))
+//
+// In this example, a message is stored in the Catalog where one of two messages
+// is selected based on the first argument, a number. The first message is
+// selected if the argument is singular (identified by the selector "one") and
+// the second message is selected in all other cases. The selectors are defined
+// by the plural rules defined in CLDR. The selector "other" is special and will
+// always match. Each language always defines one of the linguistic categories
+// to be "other." For English, singular is "one" and plural is "other".
+//
+// Selects can be nested. This allows selecting sentences based on features of
+// multiple arguments or multiple linguistic properties of a single argument.
+//
+//
+// String interpolation
+//
+// There is often a lot of commonality between the possible variants of a
+// message. For instance, in the example above the word "minute" varies based on
+// the plural catogory of the argument, but the rest of the sentence is
+// identical. Using interpolation the above message can be rewritten as:
+//
+//   catalog.Set(language.English, "You are %d minute(s) late.",
+//       catalog.Var("minutes",
+//           plural.Select(1, "one", "minute", "other", "minutes")),
+//       catalog.String("You are %[1]d ${minutes} late."))
+//
+// Var is defined to return the variable name if the message does not yield a
+// match. This allows us to further simplify this snippet to
+//
+//   catalog.Set(language.English, "You are %d minute(s) late.",
+//       catalog.Var("minutes", plural.Select(1, "one", "minute")),
+//       catalog.String("You are %d ${minutes} late."))
+//
+// Overall this is still only a minor improvement, but things can get a lot more
+// unwieldy if more than one linguistic feature is used to determine a message
+// variant. Consider the following example:
+//
+//   // argument 1: list of hosts, argument 2: list of guests
+//   catalog.Set(language.English, "%[1]v invite(s) %[2]v to their party.",
+//     catalog.Var("their",
+//         plural.Select(1,
+//             "one", gender.Select(1, "female", "her", "other", "his"))),
+//     catalog.Var("invites", plural.Select(1, "one", "invite"))
+//     catalog.String("%[1]v ${invites} %[2]v to ${their} party.")),
+//
+// Without variable substitution, this would have to be written as
+//
+//   // argument 1: list of hosts, argument 2: list of guests
+//   catalog.Set(language.English, "%[1]v invite(s) %[2]v to their party.",
+//     plural.Select(1,
+//         "one", gender.Select(1,
+//             "female", "%[1]v invites %[2]v to her party."
+//             "other", "%[1]v invites %[2]v to his party."),
+//         "other", "%[1]v invites %[2]v to their party.")
+//
+// Not necessarily shorter, but using variables there is less duplication and
+// the messages are more maintenance friendly. Moreover, languages may have up
+// to six plural forms. This makes the use of variables more welcome.
+//
+// Different messages using the same inflections can reuse variables by moving
+// them to macros. Using macros we can rewrite the message as:
+//
+//   // argument 1: list of hosts, argument 2: list of guests
+//   catalog.SetString(language.English, "%[1]v invite(s) %[2]v to their party.",
+//       "%[1]v ${invites(1)} %[2]v to ${their(1)} party.")
+//
+// Where the following macros were defined separately.
+//
+//   catalog.SetMacro(language.English, "invites", plural.Select(1, "one", "invite"))
+//   catalog.SetMacro(language.English, "their", plural.Select(1,
+//      "one", gender.Select(1, "female", "her", "other", "his"))),
+//
+// Placeholders use parentheses and the arguments to invoke a macro.
+//
+//
+// Looking up messages
+//
+// Message lookup using Catalogs is typically only done by specialized packages
+// and is not something the user should be concerned with. For instance, to
+// express the tardiness of a user using the related message we defined earlier,
+// the user may use the package message like so:
+//
+//   p := message.NewPrinter(language.English)
+//   p.Printf("You are %d minute(s) late.", 5)
+//
+// Which would print:
+//   You are 5 minutes late.
+//
+//
+// This package is UNDER CONSTRUCTION and its API may change.
+package catalog // import "golang.org/x/text/message/catalog"
+
+// TODO:
+// Some way to freeze a catalog.
+// - Locking on each lockup turns out to be about 50% of the total running time
+//   for some of the benchmarks in the message package.
+// Consider these:
+// - Sequence type to support sequences in user-defined messages.
+// - Garbage collection: Remove dictionaries that can no longer be reached
+//   as other dictionaries have been added that cover all possible keys.
+
+import (
+	"errors"
+	"fmt"
+
+	"golang.org/x/text/internal"
+
+	"golang.org/x/text/internal/catmsg"
+	"golang.org/x/text/language"
+)
+
+// A Catalog allows lookup of translated messages.
+type Catalog interface {
+	// Languages returns all languages for which the Catalog contains variants.
+	Languages() []language.Tag
+
+	// Matcher returns a Matcher for languages from this Catalog.
+	Matcher() language.Matcher
+
+	// A Context is used for evaluating Messages.
+	Context(tag language.Tag, r catmsg.Renderer) *Context
+
+	// This method also makes Catalog a private interface.
+	lookup(tag language.Tag, key string) (data string, ok bool)
+}
+
+// NewFromMap creates a Catalog from the given map. If a Dictionary is
+// underspecified the entry is retrieved from a parent language.
+func NewFromMap(dictionaries map[string]Dictionary, opts ...Option) (Catalog, error) {
+	options := options{}
+	for _, o := range opts {
+		o(&options)
+	}
+	c := &catalog{
+		dicts: map[language.Tag]Dictionary{},
+	}
+	_, hasFallback := dictionaries[options.fallback.String()]
+	if hasFallback {
+		// TODO: Should it be okay to not have a fallback language?
+		// Catalog generators could enforce there is always a fallback.
+		c.langs = append(c.langs, options.fallback)
+	}
+	for lang, dict := range dictionaries {
+		tag, err := language.Parse(lang)
+		if err != nil {
+			return nil, fmt.Errorf("catalog: invalid language tag %q", lang)
+		}
+		if _, ok := c.dicts[tag]; ok {
+			return nil, fmt.Errorf("catalog: duplicate entry for tag %q after normalization", tag)
+		}
+		c.dicts[tag] = dict
+		if !hasFallback || tag != options.fallback {
+			c.langs = append(c.langs, tag)
+		}
+	}
+	if hasFallback {
+		internal.SortTags(c.langs[1:])
+	} else {
+		internal.SortTags(c.langs)
+	}
+	c.matcher = language.NewMatcher(c.langs)
+	return c, nil
+}
+
+// A Dictionary is a source of translations for a single language.
+type Dictionary interface {
+	// Lookup returns a message compiled with catmsg.Compile for the given key.
+	// It returns false for ok if such a message could not be found.
+	Lookup(key string) (data string, ok bool)
+}
+
+type catalog struct {
+	langs   []language.Tag
+	dicts   map[language.Tag]Dictionary
+	macros  store
+	matcher language.Matcher
+}
+
+func (c *catalog) Languages() []language.Tag { return c.langs }
+func (c *catalog) Matcher() language.Matcher { return c.matcher }
+
+func (c *catalog) lookup(tag language.Tag, key string) (data string, ok bool) {
+	for ; ; tag = tag.Parent() {
+		if dict, ok := c.dicts[tag]; ok {
+			if data, ok := dict.Lookup(key); ok {
+				return data, true
+			}
+		}
+		if tag == language.Und {
+			break
+		}
+	}
+	return "", false
+}
+
+// Context returns a Context for formatting messages.
+// Only one Message may be formatted per context at any given time.
+func (c *catalog) Context(tag language.Tag, r catmsg.Renderer) *Context {
+	return &Context{
+		cat: c,
+		tag: tag,
+		dec: catmsg.NewDecoder(tag, r, &dict{&c.macros, tag}),
+	}
+}
+
+// A Builder allows building a Catalog programmatically.
+type Builder struct {
+	options
+	matcher language.Matcher
+
+	index  store
+	macros store
+}
+
+type options struct {
+	fallback language.Tag
+}
+
+// An Option configures Catalog behavior.
+type Option func(*options)
+
+// Fallback specifies the default fallback language. The default is Und.
+func Fallback(tag language.Tag) Option {
+	return func(o *options) { o.fallback = tag }
+}
+
+// TODO:
+// // Catalogs specifies one or more sources for a Catalog.
+// // Lookups are in order.
+// // This can be changed inserting a Catalog used for setting, which implements
+// // Loader, used for setting in the chain.
+// func Catalogs(d ...Loader) Option {
+// 	return nil
+// }
+//
+// func Delims(start, end string) Option {}
+//
+// func Dict(tag language.Tag, d ...Dictionary) Option
+
+// NewBuilder returns an empty mutable Catalog.
+func NewBuilder(opts ...Option) *Builder {
+	c := &Builder{}
+	for _, o := range opts {
+		o(&c.options)
+	}
+	return c
+}
+
+// SetString is shorthand for Set(tag, key, String(msg)).
+func (c *Builder) SetString(tag language.Tag, key string, msg string) error {
+	return c.set(tag, key, &c.index, String(msg))
+}
+
+// Set sets the translation for the given language and key.
+//
+// When evaluation this message, the first Message in the sequence to msgs to
+// evaluate to a string will be the message returned.
+func (c *Builder) Set(tag language.Tag, key string, msg ...Message) error {
+	return c.set(tag, key, &c.index, msg...)
+}
+
+// SetMacro defines a Message that may be substituted in another message.
+// The arguments to a macro Message are passed as arguments in the
+// placeholder the form "${foo(arg1, arg2)}".
+func (c *Builder) SetMacro(tag language.Tag, name string, msg ...Message) error {
+	return c.set(tag, name, &c.macros, msg...)
+}
+
+// ErrNotFound indicates there was no message for the given key.
+var ErrNotFound = errors.New("catalog: message not found")
+
+// String specifies a plain message string. It can be used as fallback if no
+// other strings match or as a simple standalone message.
+//
+// It is an error to pass more than one String in a message sequence.
+func String(name string) Message {
+	return catmsg.String(name)
+}
+
+// Var sets a variable that may be substituted in formatting patterns using
+// named substitution of the form "${name}". The name argument is used as a
+// fallback if the statements do not produce a match. The statement sequence may
+// not contain any Var calls.
+//
+// The name passed to a Var must be unique within message sequence.
+func Var(name string, msg ...Message) Message {
+	return &catmsg.Var{Name: name, Message: firstInSequence(msg)}
+}
+
+// Context returns a Context for formatting messages.
+// Only one Message may be formatted per context at any given time.
+func (b *Builder) Context(tag language.Tag, r catmsg.Renderer) *Context {
+	return &Context{
+		cat: b,
+		tag: tag,
+		dec: catmsg.NewDecoder(tag, r, &dict{&b.macros, tag}),
+	}
+}
+
+// A Context is used for evaluating Messages.
+// Only one Message may be formatted per context at any given time.
+type Context struct {
+	cat Catalog
+	tag language.Tag // TODO: use compact index.
+	dec *catmsg.Decoder
+}
+
+// Execute looks up and executes the message with the given key.
+// It returns ErrNotFound if no message could be found in the index.
+func (c *Context) Execute(key string) error {
+	data, ok := c.cat.lookup(c.tag, key)
+	if !ok {
+		return ErrNotFound
+	}
+	return c.dec.Execute(data)
+}

vendor/golang.org/x/text/message/catalog/catalog_test.go

@@ -0,0 +1,296 @@
+// 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 catalog
+
+import (
+	"bytes"
+	"path"
+	"reflect"
+	"strings"
+	"testing"
+
+	"golang.org/x/text/internal/catmsg"
+	"golang.org/x/text/language"
+)
+
+type entry struct {
+	tag, key string
+	msg      interface{}
+}
+
+func langs(s string) []language.Tag {
+	t, _, _ := language.ParseAcceptLanguage(s)
+	return t
+}
+
+type testCase struct {
+	desc     string
+	cat      []entry
+	lookup   []entry
+	fallback string
+	match    []string
+	tags     []language.Tag
+}
+
+var testCases = []testCase{{
+	desc: "empty catalog",
+	lookup: []entry{
+		{"en", "key", ""},
+		{"en", "", ""},
+		{"nl", "", ""},
+	},
+	match: []string{
+		"gr -> und",
+		"en-US -> und",
+		"af -> und",
+	},
+	tags: nil, // not an empty list.
+}, {
+	desc: "one entry",
+	cat: []entry{
+		{"en", "hello", "Hello!"},
+	},
+	lookup: []entry{
+		{"und", "hello", ""},
+		{"nl", "hello", ""},
+		{"en", "hello", "Hello!"},
+		{"en-US", "hello", "Hello!"},
+		{"en-GB", "hello", "Hello!"},
+		{"en-oxendict", "hello", "Hello!"},
+		{"en-oxendict-u-ms-metric", "hello", "Hello!"},
+	},
+	match: []string{
+		"gr -> en",
+		"en-US -> en",
+	},
+	tags: langs("en"),
+}, {
+	desc: "hierarchical languages",
+	cat: []entry{
+		{"en", "hello", "Hello!"},
+		{"en-GB", "hello", "Hellø!"},
+		{"en-US", "hello", "Howdy!"},
+		{"en", "greetings", "Greetings!"},
+		{"gsw", "hello", "Grüetzi!"},
+	},
+	lookup: []entry{
+		{"und", "hello", ""},
+		{"nl", "hello", ""},
+		{"en", "hello", "Hello!"},
+		{"en-US", "hello", "Howdy!"},
+		{"en-GB", "hello", "Hellø!"},
+		{"en-oxendict", "hello", "Hello!"},
+		{"en-US-oxendict-u-ms-metric", "hello", "Howdy!"},
+
+		{"und", "greetings", ""},
+		{"nl", "greetings", ""},
+		{"en", "greetings", "Greetings!"},
+		{"en-US", "greetings", "Greetings!"},
+		{"en-GB", "greetings", "Greetings!"},
+		{"en-oxendict", "greetings", "Greetings!"},
+		{"en-US-oxendict-u-ms-metric", "greetings", "Greetings!"},
+	},
+	fallback: "gsw",
+	match: []string{
+		"gr -> gsw",
+		"en-US -> en-US",
+	},
+	tags: langs("gsw, en, en-GB, en-US"),
+}, {
+	desc: "variables",
+	cat: []entry{
+		{"en", "hello %s", []Message{
+			Var("person", String("Jane")),
+			String("Hello ${person}!"),
+		}},
+		{"en", "hello error", []Message{
+			Var("person", String("Jane")),
+			noMatchMessage{}, // trigger sequence path.
+			String("Hello ${person."),
+		}},
+		{"en", "fallback to var value", []Message{
+			Var("you", noMatchMessage{}, noMatchMessage{}),
+			String("Hello ${you}."),
+		}},
+		{"en", "scopes", []Message{
+			Var("person1", String("Mark")),
+			Var("person2", String("Jane")),
+			Var("couple",
+				Var("person1", String("Joe")),
+				String("${person1} and ${person2}")),
+			String("Hello ${couple}."),
+		}},
+		{"en", "missing var", String("Hello ${missing}.")},
+	},
+	lookup: []entry{
+		{"en", "hello %s", "Hello Jane!"},
+		{"en", "hello error", "Hello $!(MISSINGBRACE)"},
+		{"en", "fallback to var value", "Hello you."},
+		{"en", "scopes", "Hello Joe and Jane."},
+		{"en", "missing var", "Hello missing."},
+	},
+	tags: langs("en"),
+}, {
+	desc: "macros",
+	cat: []entry{
+		{"en", "macro1", String("Hello ${macro1(1)}.")},
+		{"en", "macro2", String("Hello ${ macro1(2) }!")},
+		{"en", "macroWS", String("Hello ${ macro1( 2 ) }!")},
+		{"en", "missing", String("Hello ${ missing(1 }.")},
+		{"en", "badnum", String("Hello ${ badnum(1b) }.")},
+		{"en", "undefined", String("Hello ${ undefined(1) }.")},
+		{"en", "macroU", String("Hello ${ macroU(2) }!")},
+	},
+	lookup: []entry{
+		{"en", "macro1", "Hello Joe."},
+		{"en", "macro2", "Hello Joe!"},
+		{"en-US", "macroWS", "Hello Joe!"},
+		{"en-NL", "missing", "Hello $!(MISSINGPAREN)."},
+		{"en", "badnum", "Hello $!(BADNUM)."},
+		{"en", "undefined", "Hello undefined."},
+		{"en", "macroU", "Hello macroU!"},
+	},
+	tags: langs("en"),
+}}
+
+func setMacros(b *Builder) {
+	b.SetMacro(language.English, "macro1", String("Joe"))
+	b.SetMacro(language.Und, "macro2", String("${macro1(1)}"))
+	b.SetMacro(language.English, "macroU", noMatchMessage{})
+}
+
+type buildFunc func(t *testing.T, tc testCase) Catalog
+
+func initBuilder(t *testing.T, tc testCase) Catalog {
+	options := []Option{}
+	if tc.fallback != "" {
+		options = append(options, Fallback(language.MustParse(tc.fallback)))
+	}
+	cat := NewBuilder(options...)
+	for _, e := range tc.cat {
+		tag := language.MustParse(e.tag)
+		switch msg := e.msg.(type) {
+		case string:
+
+			cat.SetString(tag, e.key, msg)
+		case Message:
+			cat.Set(tag, e.key, msg)
+		case []Message:
+			cat.Set(tag, e.key, msg...)
+		}
+	}
+	setMacros(cat)
+	return cat
+}
+
+type dictionary map[string]string
+
+func (d dictionary) Lookup(key string) (data string, ok bool) {
+	data, ok = d[key]
+	return data, ok
+}
+
+func initCatalog(t *testing.T, tc testCase) Catalog {
+	m := map[string]Dictionary{}
+	for _, e := range tc.cat {
+		m[e.tag] = dictionary{}
+	}
+	for _, e := range tc.cat {
+		var msg Message
+		switch x := e.msg.(type) {
+		case string:
+			msg = String(x)
+		case Message:
+			msg = x
+		case []Message:
+			msg = firstInSequence(x)
+		}
+		data, _ := catmsg.Compile(language.MustParse(e.tag), nil, msg)
+		m[e.tag].(dictionary)[e.key] = data
+	}
+	options := []Option{}
+	if tc.fallback != "" {
+		options = append(options, Fallback(language.MustParse(tc.fallback)))
+	}
+	c, err := NewFromMap(m, options...)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// TODO: implement macros for fixed catalogs.
+	b := NewBuilder()
+	setMacros(b)
+	c.(*catalog).macros.index = b.macros.index
+	return c
+}
+
+func TestMatcher(t *testing.T) {
+	test := func(t *testing.T, init buildFunc) {
+		for _, tc := range testCases {
+			for _, s := range tc.match {
+				a := strings.Split(s, "->")
+				t.Run(path.Join(tc.desc, a[0]), func(t *testing.T) {
+					cat := init(t, tc)
+					got, _ := language.MatchStrings(cat.Matcher(), a[0])
+					want := language.MustParse(strings.TrimSpace(a[1]))
+					if got != want {
+						t.Errorf("got %q; want %q", got, want)
+					}
+				})
+			}
+		}
+	}
+	t.Run("Builder", func(t *testing.T) { test(t, initBuilder) })
+	t.Run("Catalog", func(t *testing.T) { test(t, initCatalog) })
+}
+
+func TestCatalog(t *testing.T) {
+	test := func(t *testing.T, init buildFunc) {
+		for _, tc := range testCases {
+			cat := init(t, tc)
+			wantTags := tc.tags
+			if got := cat.Languages(); !reflect.DeepEqual(got, wantTags) {
+				t.Errorf("%s:Languages: got %v; want %v", tc.desc, got, wantTags)
+			}
+
+			for _, e := range tc.lookup {
+				t.Run(path.Join(tc.desc, e.tag, e.key), func(t *testing.T) {
+					tag := language.MustParse(e.tag)
+					buf := testRenderer{}
+					ctx := cat.Context(tag, &buf)
+					want := e.msg.(string)
+					err := ctx.Execute(e.key)
+					gotFound := err != ErrNotFound
+					wantFound := want != ""
+					if gotFound != wantFound {
+						t.Fatalf("err: got %v (%v); want %v", gotFound, err, wantFound)
+					}
+					if got := buf.buf.String(); got != want {
+						t.Errorf("Lookup:\ngot  %q\nwant %q", got, want)
+					}
+				})
+			}
+		}
+	}
+	t.Run("Builder", func(t *testing.T) { test(t, initBuilder) })
+	t.Run("Catalog", func(t *testing.T) { test(t, initCatalog) })
+}
+
+type testRenderer struct {
+	buf bytes.Buffer
+}
+
+func (f *testRenderer) Arg(i int) interface{} { return nil }
+func (f *testRenderer) Render(s string)       { f.buf.WriteString(s) }
+
+var msgNoMatch = catmsg.Register("no match", func(d *catmsg.Decoder) bool {
+	return false // no match
+})
+
+type noMatchMessage struct{}
+
+func (noMatchMessage) Compile(e *catmsg.Encoder) error {
+	e.EncodeMessageType(msgNoMatch)
+	return catmsg.ErrIncomplete
+}

vendor/golang.org/x/text/message/catalog/dict.go

@@ -0,0 +1,129 @@
+// 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 catalog
+
+import (
+	"sync"
+
+	"golang.org/x/text/internal"
+	"golang.org/x/text/internal/catmsg"
+	"golang.org/x/text/language"
+)
+
+// TODO:
+// Dictionary returns a Dictionary that returns the first Message, using the
+// given language tag, that matches:
+//   1. the last one registered by one of the Set methods
+//   2. returned by one of the Loaders
+//   3. repeat from 1. using the parent language
+// This approach allows messages to be underspecified.
+// func (c *Catalog) Dictionary(tag language.Tag) (Dictionary, error) {
+// 	// TODO: verify dictionary exists.
+// 	return &dict{&c.index, tag}, nil
+// }
+
+type dict struct {
+	s   *store
+	tag language.Tag // TODO: make compact tag.
+}
+
+func (d *dict) Lookup(key string) (data string, ok bool) {
+	return d.s.lookup(d.tag, key)
+}
+
+func (b *Builder) lookup(tag language.Tag, key string) (data string, ok bool) {
+	return b.index.lookup(tag, key)
+}
+
+func (c *Builder) set(tag language.Tag, key string, s *store, msg ...Message) error {
+	data, err := catmsg.Compile(tag, &dict{&c.macros, tag}, firstInSequence(msg))
+
+	s.mutex.Lock()
+	defer s.mutex.Unlock()
+
+	m := s.index[tag]
+	if m == nil {
+		m = msgMap{}
+		if s.index == nil {
+			s.index = map[language.Tag]msgMap{}
+		}
+		c.matcher = nil
+		s.index[tag] = m
+	}
+
+	m[key] = data
+	return err
+}
+
+func (c *Builder) Matcher() language.Matcher {
+	c.index.mutex.RLock()
+	m := c.matcher
+	c.index.mutex.RUnlock()
+	if m != nil {
+		return m
+	}
+
+	c.index.mutex.Lock()
+	if c.matcher == nil {
+		c.matcher = language.NewMatcher(c.unlockedLanguages())
+	}
+	m = c.matcher
+	c.index.mutex.Unlock()
+	return m
+}
+
+type store struct {
+	mutex sync.RWMutex
+	index map[language.Tag]msgMap
+}
+
+type msgMap map[string]string
+
+func (s *store) lookup(tag language.Tag, key string) (data string, ok bool) {
+	s.mutex.RLock()
+	defer s.mutex.RUnlock()
+
+	for ; ; tag = tag.Parent() {
+		if msgs, ok := s.index[tag]; ok {
+			if msg, ok := msgs[key]; ok {
+				return msg, true
+			}
+		}
+		if tag == language.Und {
+			break
+		}
+	}
+	return "", false
+}
+
+// Languages returns all languages for which the Catalog contains variants.
+func (b *Builder) Languages() []language.Tag {
+	s := &b.index
+	s.mutex.RLock()
+	defer s.mutex.RUnlock()
+
+	return b.unlockedLanguages()
+}
+
+func (b *Builder) unlockedLanguages() []language.Tag {
+	s := &b.index
+	if len(s.index) == 0 {
+		return nil
+	}
+	tags := make([]language.Tag, 0, len(s.index))
+	_, hasFallback := s.index[b.options.fallback]
+	offset := 0
+	if hasFallback {
+		tags = append(tags, b.options.fallback)
+		offset = 1
+	}
+	for t := range s.index {
+		if t != b.options.fallback {
+			tags = append(tags, t)
+		}
+	}
+	internal.SortTags(tags[offset:])
+	return tags
+}

vendor/golang.org/x/text/message/catalog/go19.go

@@ -0,0 +1,15 @@
+// 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.
+
+// +build go1.9
+
+package catalog
+
+import "golang.org/x/text/internal/catmsg"
+
+// A Message holds a collection of translations for the same phrase that may
+// vary based on the values of substitution arguments.
+type Message = catmsg.Message
+
+type firstInSequence = catmsg.FirstOf

vendor/golang.org/x/text/message/catalog/gopre19.go

@@ -0,0 +1,23 @@
+// 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.
+
+// +build !go1.9
+
+package catalog
+
+import "golang.org/x/text/internal/catmsg"
+
+// A Message holds a collection of translations for the same phrase that may
+// vary based on the values of substitution arguments.
+type Message interface {
+	catmsg.Message
+}
+
+func firstInSequence(m []Message) catmsg.Message {
+	a := []catmsg.Message{}
+	for _, m := range m {
+		a = append(a, m)
+	}
+	return catmsg.FirstOf(a)
+}

vendor/golang.org/x/text/message/catalog_test.go

@@ -0,0 +1,43 @@
+// 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 message
+
+import (
+	"strings"
+	"testing"
+
+	"golang.org/x/text/language"
+	"golang.org/x/text/message/catalog"
+)
+
+func TestMatchLanguage(t *testing.T) {
+	c := catalog.NewBuilder(catalog.Fallback(language.English))
+	c.SetString(language.Bengali, "", "")
+	c.SetString(language.English, "", "")
+	c.SetString(language.German, "", "")
+
+	testCases := []struct {
+		args string // '|'-separated list
+		want string
+	}{{
+		args: "de-CH",
+		want: "de",
+	}, {
+		args: "bn-u-nu-latn|en-US,en;q=0.9,de;q=0.8,nl;q=0.7",
+		want: "bn-u-nu-latn",
+	}, {
+		args: "gr",
+		want: "en",
+	}}
+	for _, tc := range testCases {
+		DefaultCatalog = c
+		t.Run(tc.args, func(t *testing.T) {
+			got := MatchLanguage(strings.Split(tc.args, "|")...)
+			if got != language.Make(tc.want) {
+				t.Errorf("got %q; want %q", got, tc.want)
+			}
+		})
+	}
+}

vendor/golang.org/x/text/message/doc.go

@@ -0,0 +1,100 @@
+// 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 message implements formatted I/O for localized strings with functions
+// analogous to the fmt's print functions. It is a drop-in replacement for fmt.
+//
+//
+// Localized Formatting
+//
+// A format string can be localized by replacing any of the print functions of
+// fmt with an equivalent call to a Printer.
+//
+//    p := message.NewPrinter(message.MatchLanguage("en"))
+//    p.Println(123456.78) // Prints 123,456.78
+//
+//    p.Printf("%d ducks in a row", 4331) // Prints 4,331 ducks in a row
+//
+//    p := message.NewPrinter(message.MatchLanguage("nl"))
+//    p.Println("Hoogte: %f meter", 1244.9) // Prints Hoogte: 1.244,9 meter
+//
+//    p := message.NewPrinter(message.MatchLanguage("bn"))
+//    p.Println(123456.78) // Prints ১,২৩,৪৫৬.৭৮
+//
+// Printer currently supports numbers and specialized types for which packages
+// exist in x/text. Other builtin types such as time.Time and slices are
+// planned.
+//
+// Format strings largely have the same meaning as with fmt with the following
+// notable exceptions:
+//   - flag # always resorts to fmt for printing
+//   - verb 'f', 'e', 'g', 'd' use localized formatting unless the '#' flag is
+//     specified.
+//
+// See package fmt for more options.
+//
+//
+// Translation
+//
+// The format strings that are passed to Printf, Sprintf, Fprintf, or Errorf
+// are used as keys to look up translations for the specified languages.
+// More on how these need to be specified below.
+//
+// One can use arbitrary keys to distinguish between otherwise ambiguous
+// strings:
+//    p := message.NewPrinter(language.English)
+//    p.Printf("archive(noun)")  // Prints "archive"
+//    p.Printf("archive(verb)")  // Prints "archive"
+//
+//    p := message.NewPrinter(language.German)
+//    p.Printf("archive(noun)")  // Prints "Archiv"
+//    p.Printf("archive(verb)")  // Prints "archivieren"
+//
+// To retain the fallback functionality, use Key:
+//    p.Printf(message.Key("archive(noun)", "archive"))
+//    p.Printf(message.Key("archive(verb)", "archive"))
+//
+//
+// Translation Pipeline
+//
+// Format strings that contain text need to be translated to support different
+// locales. The first step is to extract strings that need to be translated.
+//
+// 1. Install gotext
+//    go get -u golang.org/x/text/cmd/gotext
+//    gotext -help
+//
+// 2. Mark strings in your source to be translated by using message.Printer,
+// instead of the functions of the fmt package.
+//
+// 3. Extract the strings from your source
+//
+//    gotext extract
+//
+// The output will be written to the textdata directory.
+//
+// 4. Send the files for translation
+//
+// It is planned to support multiple formats, but for now one will have to
+// rewrite the JSON output to the desired format.
+//
+// 5. Inject translations into program
+//
+// 6. Repeat from 2
+//
+// Right now this has to be done programmatically with calls to Set or
+// SetString. These functions as well as the methods defined in
+// see also package golang.org/x/text/message/catalog can be used to implement
+// either dynamic or static loading of messages.
+//
+//
+// Plural and Gender Forms
+//
+// Translated messages can vary based on the plural and gender forms of
+// substitution values. In general, it is up to the translators to provide
+// alternative translations for such forms. See the packages in
+// golang.org/x/text/feature and golang.org/x/text/message/catalog for more
+// information.
+//
+package message

vendor/golang.org/x/text/message/examples_test.go

@@ -0,0 +1,42 @@
+// 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 message_test
+
+import (
+	"net/http"
+
+	"golang.org/x/text/language"
+	"golang.org/x/text/message"
+)
+
+func Example_http() {
+	// languages supported by this service:
+	matcher := language.NewMatcher(message.DefaultCatalog.Languages())
+
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		lang, _ := r.Cookie("lang")
+		accept := r.Header.Get("Accept-Language")
+		fallback := "en"
+		tag, _ := language.MatchStrings(matcher, lang.String(), accept, fallback)
+
+		p := message.NewPrinter(tag)
+
+		p.Fprintln(w, "User language is", tag)
+	})
+}
+
+func ExamplePrinter_numbers() {
+	for _, lang := range []string{"en", "de", "de-CH", "fr", "bn"} {
+		p := message.NewPrinter(language.Make(lang))
+		p.Printf("%-6s %g\n", lang, 123456.78)
+	}
+
+	// Output:
+	// en     123,456.78
+	// de     123.456,78
+	// de-CH  123’456.78
+	// fr     123 456,78
+	// bn     ১,২৩,৪৫৬.৭৮
+}

vendor/golang.org/x/text/message/format.go

@@ -0,0 +1,510 @@
+// 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 message
+
+import (
+	"bytes"
+	"strconv"
+	"unicode/utf8"
+
+	"golang.org/x/text/internal/format"
+)
+
+const (
+	ldigits = "0123456789abcdefx"
+	udigits = "0123456789ABCDEFX"
+)
+
+const (
+	signed   = true
+	unsigned = false
+)
+
+// A formatInfo is the raw formatter used by Printf etc.
+// It prints into a buffer that must be set up separately.
+type formatInfo struct {
+	buf *bytes.Buffer
+
+	format.Parser
+
+	// intbuf is large enough to store %b of an int64 with a sign and
+	// avoids padding at the end of the struct on 32 bit architectures.
+	intbuf [68]byte
+}
+
+func (f *formatInfo) init(buf *bytes.Buffer) {
+	f.ClearFlags()
+	f.buf = buf
+}
+
+// writePadding generates n bytes of padding.
+func (f *formatInfo) writePadding(n int) {
+	if n <= 0 { // No padding bytes needed.
+		return
+	}
+	f.buf.Grow(n)
+	// Decide which byte the padding should be filled with.
+	padByte := byte(' ')
+	if f.Zero {
+		padByte = byte('0')
+	}
+	// Fill padding with padByte.
+	for i := 0; i < n; i++ {
+		f.buf.WriteByte(padByte) // TODO: make more efficient.
+	}
+}
+
+// pad appends b to f.buf, padded on left (!f.minus) or right (f.minus).
+func (f *formatInfo) pad(b []byte) {
+	if !f.WidthPresent || f.Width == 0 {
+		f.buf.Write(b)
+		return
+	}
+	width := f.Width - utf8.RuneCount(b)
+	if !f.Minus {
+		// left padding
+		f.writePadding(width)
+		f.buf.Write(b)
+	} else {
+		// right padding
+		f.buf.Write(b)
+		f.writePadding(width)
+	}
+}
+
+// padString appends s to f.buf, padded on left (!f.minus) or right (f.minus).
+func (f *formatInfo) padString(s string) {
+	if !f.WidthPresent || f.Width == 0 {
+		f.buf.WriteString(s)
+		return
+	}
+	width := f.Width - utf8.RuneCountInString(s)
+	if !f.Minus {
+		// left padding
+		f.writePadding(width)
+		f.buf.WriteString(s)
+	} else {
+		// right padding
+		f.buf.WriteString(s)
+		f.writePadding(width)
+	}
+}
+
+// fmt_boolean formats a boolean.
+func (f *formatInfo) fmt_boolean(v bool) {
+	if v {
+		f.padString("true")
+	} else {
+		f.padString("false")
+	}
+}
+
+// fmt_unicode formats a uint64 as "U+0078" or with f.sharp set as "U+0078 'x'".
+func (f *formatInfo) fmt_unicode(u uint64) {
+	buf := f.intbuf[0:]
+
+	// With default precision set the maximum needed buf length is 18
+	// for formatting -1 with %#U ("U+FFFFFFFFFFFFFFFF") which fits
+	// into the already allocated intbuf with a capacity of 68 bytes.
+	prec := 4
+	if f.PrecPresent && f.Prec > 4 {
+		prec = f.Prec
+		// Compute space needed for "U+" , number, " '", character, "'".
+		width := 2 + prec + 2 + utf8.UTFMax + 1
+		if width > len(buf) {
+			buf = make([]byte, width)
+		}
+	}
+
+	// Format into buf, ending at buf[i]. Formatting numbers is easier right-to-left.
+	i := len(buf)
+
+	// For %#U we want to add a space and a quoted character at the end of the buffer.
+	if f.Sharp && u <= utf8.MaxRune && strconv.IsPrint(rune(u)) {
+		i--
+		buf[i] = '\''
+		i -= utf8.RuneLen(rune(u))
+		utf8.EncodeRune(buf[i:], rune(u))
+		i--
+		buf[i] = '\''
+		i--
+		buf[i] = ' '
+	}
+	// Format the Unicode code point u as a hexadecimal number.
+	for u >= 16 {
+		i--
+		buf[i] = udigits[u&0xF]
+		prec--
+		u >>= 4
+	}
+	i--
+	buf[i] = udigits[u]
+	prec--
+	// Add zeros in front of the number until requested precision is reached.
+	for prec > 0 {
+		i--
+		buf[i] = '0'
+		prec--
+	}
+	// Add a leading "U+".
+	i--
+	buf[i] = '+'
+	i--
+	buf[i] = 'U'
+
+	oldZero := f.Zero
+	f.Zero = false
+	f.pad(buf[i:])
+	f.Zero = oldZero
+}
+
+// fmt_integer formats signed and unsigned integers.
+func (f *formatInfo) fmt_integer(u uint64, base int, isSigned bool, digits string) {
+	negative := isSigned && int64(u) < 0
+	if negative {
+		u = -u
+	}
+
+	buf := f.intbuf[0:]
+	// The already allocated f.intbuf with a capacity of 68 bytes
+	// is large enough for integer formatting when no precision or width is set.
+	if f.WidthPresent || f.PrecPresent {
+		// Account 3 extra bytes for possible addition of a sign and "0x".
+		width := 3 + f.Width + f.Prec // wid and prec are always positive.
+		if width > len(buf) {
+			// We're going to need a bigger boat.
+			buf = make([]byte, width)
+		}
+	}
+
+	// Two ways to ask for extra leading zero digits: %.3d or %03d.
+	// If both are specified the f.zero flag is ignored and
+	// padding with spaces is used instead.
+	prec := 0
+	if f.PrecPresent {
+		prec = f.Prec
+		// Precision of 0 and value of 0 means "print nothing" but padding.
+		if prec == 0 && u == 0 {
+			oldZero := f.Zero
+			f.Zero = false
+			f.writePadding(f.Width)
+			f.Zero = oldZero
+			return
+		}
+	} else if f.Zero && f.WidthPresent {
+		prec = f.Width
+		if negative || f.Plus || f.Space {
+			prec-- // leave room for sign
+		}
+	}
+
+	// Because printing is easier right-to-left: format u into buf, ending at buf[i].
+	// We could make things marginally faster by splitting the 32-bit case out
+	// into a separate block but it's not worth the duplication, so u has 64 bits.
+	i := len(buf)
+	// Use constants for the division and modulo for more efficient code.
+	// Switch cases ordered by popularity.
+	switch base {
+	case 10:
+		for u >= 10 {
+			i--
+			next := u / 10
+			buf[i] = byte('0' + u - next*10)
+			u = next
+		}
+	case 16:
+		for u >= 16 {
+			i--
+			buf[i] = digits[u&0xF]
+			u >>= 4
+		}
+	case 8:
+		for u >= 8 {
+			i--
+			buf[i] = byte('0' + u&7)
+			u >>= 3
+		}
+	case 2:
+		for u >= 2 {
+			i--
+			buf[i] = byte('0' + u&1)
+			u >>= 1
+		}
+	default:
+		panic("fmt: unknown base; can't happen")
+	}
+	i--
+	buf[i] = digits[u]
+	for i > 0 && prec > len(buf)-i {
+		i--
+		buf[i] = '0'
+	}
+
+	// Various prefixes: 0x, -, etc.
+	if f.Sharp {
+		switch base {
+		case 8:
+			if buf[i] != '0' {
+				i--
+				buf[i] = '0'
+			}
+		case 16:
+			// Add a leading 0x or 0X.
+			i--
+			buf[i] = digits[16]
+			i--
+			buf[i] = '0'
+		}
+	}
+
+	if negative {
+		i--
+		buf[i] = '-'
+	} else if f.Plus {
+		i--
+		buf[i] = '+'
+	} else if f.Space {
+		i--
+		buf[i] = ' '
+	}
+
+	// Left padding with zeros has already been handled like precision earlier
+	// or the f.zero flag is ignored due to an explicitly set precision.
+	oldZero := f.Zero
+	f.Zero = false
+	f.pad(buf[i:])
+	f.Zero = oldZero
+}
+
+// truncate truncates the string to the specified precision, if present.
+func (f *formatInfo) truncate(s string) string {
+	if f.PrecPresent {
+		n := f.Prec
+		for i := range s {
+			n--
+			if n < 0 {
+				return s[:i]
+			}
+		}
+	}
+	return s
+}
+
+// fmt_s formats a string.
+func (f *formatInfo) fmt_s(s string) {
+	s = f.truncate(s)
+	f.padString(s)
+}
+
+// fmt_sbx formats a string or byte slice as a hexadecimal encoding of its bytes.
+func (f *formatInfo) fmt_sbx(s string, b []byte, digits string) {
+	length := len(b)
+	if b == nil {
+		// No byte slice present. Assume string s should be encoded.
+		length = len(s)
+	}
+	// Set length to not process more bytes than the precision demands.
+	if f.PrecPresent && f.Prec < length {
+		length = f.Prec
+	}
+	// Compute width of the encoding taking into account the f.sharp and f.space flag.
+	width := 2 * length
+	if width > 0 {
+		if f.Space {
+			// Each element encoded by two hexadecimals will get a leading 0x or 0X.
+			if f.Sharp {
+				width *= 2
+			}
+			// Elements will be separated by a space.
+			width += length - 1
+		} else if f.Sharp {
+			// Only a leading 0x or 0X will be added for the whole string.
+			width += 2
+		}
+	} else { // The byte slice or string that should be encoded is empty.
+		if f.WidthPresent {
+			f.writePadding(f.Width)
+		}
+		return
+	}
+	// Handle padding to the left.
+	if f.WidthPresent && f.Width > width && !f.Minus {
+		f.writePadding(f.Width - width)
+	}
+	// Write the encoding directly into the output buffer.
+	buf := f.buf
+	if f.Sharp {
+		// Add leading 0x or 0X.
+		buf.WriteByte('0')
+		buf.WriteByte(digits[16])
+	}
+	var c byte
+	for i := 0; i < length; i++ {
+		if f.Space && i > 0 {
+			// Separate elements with a space.
+			buf.WriteByte(' ')
+			if f.Sharp {
+				// Add leading 0x or 0X for each element.
+				buf.WriteByte('0')
+				buf.WriteByte(digits[16])
+			}
+		}
+		if b != nil {
+			c = b[i] // Take a byte from the input byte slice.
+		} else {
+			c = s[i] // Take a byte from the input string.
+		}
+		// Encode each byte as two hexadecimal digits.
+		buf.WriteByte(digits[c>>4])
+		buf.WriteByte(digits[c&0xF])
+	}
+	// Handle padding to the right.
+	if f.WidthPresent && f.Width > width && f.Minus {
+		f.writePadding(f.Width - width)
+	}
+}
+
+// fmt_sx formats a string as a hexadecimal encoding of its bytes.
+func (f *formatInfo) fmt_sx(s, digits string) {
+	f.fmt_sbx(s, nil, digits)
+}
+
+// fmt_bx formats a byte slice as a hexadecimal encoding of its bytes.
+func (f *formatInfo) fmt_bx(b []byte, digits string) {
+	f.fmt_sbx("", b, digits)
+}
+
+// fmt_q formats a string as a double-quoted, escaped Go string constant.
+// If f.sharp is set a raw (backquoted) string may be returned instead
+// if the string does not contain any control characters other than tab.
+func (f *formatInfo) fmt_q(s string) {
+	s = f.truncate(s)
+	if f.Sharp && strconv.CanBackquote(s) {
+		f.padString("`" + s + "`")
+		return
+	}
+	buf := f.intbuf[:0]
+	if f.Plus {
+		f.pad(strconv.AppendQuoteToASCII(buf, s))
+	} else {
+		f.pad(strconv.AppendQuote(buf, s))
+	}
+}
+
+// fmt_c formats an integer as a Unicode character.
+// If the character is not valid Unicode, it will print '\ufffd'.
+func (f *formatInfo) fmt_c(c uint64) {
+	r := rune(c)
+	if c > utf8.MaxRune {
+		r = utf8.RuneError
+	}
+	buf := f.intbuf[:0]
+	w := utf8.EncodeRune(buf[:utf8.UTFMax], r)
+	f.pad(buf[:w])
+}
+
+// fmt_qc formats an integer as a single-quoted, escaped Go character constant.
+// If the character is not valid Unicode, it will print '\ufffd'.
+func (f *formatInfo) fmt_qc(c uint64) {
+	r := rune(c)
+	if c > utf8.MaxRune {
+		r = utf8.RuneError
+	}
+	buf := f.intbuf[:0]
+	if f.Plus {
+		f.pad(strconv.AppendQuoteRuneToASCII(buf, r))
+	} else {
+		f.pad(strconv.AppendQuoteRune(buf, r))
+	}
+}
+
+// fmt_float formats a float64. It assumes that verb is a valid format specifier
+// for strconv.AppendFloat and therefore fits into a byte.
+func (f *formatInfo) fmt_float(v float64, size int, verb rune, prec int) {
+	// Explicit precision in format specifier overrules default precision.
+	if f.PrecPresent {
+		prec = f.Prec
+	}
+	// Format number, reserving space for leading + sign if needed.
+	num := strconv.AppendFloat(f.intbuf[:1], v, byte(verb), prec, size)
+	if num[1] == '-' || num[1] == '+' {
+		num = num[1:]
+	} else {
+		num[0] = '+'
+	}
+	// f.space means to add a leading space instead of a "+" sign unless
+	// the sign is explicitly asked for by f.plus.
+	if f.Space && num[0] == '+' && !f.Plus {
+		num[0] = ' '
+	}
+	// Special handling for infinities and NaN,
+	// which don't look like a number so shouldn't be padded with zeros.
+	if num[1] == 'I' || num[1] == 'N' {
+		oldZero := f.Zero
+		f.Zero = false
+		// Remove sign before NaN if not asked for.
+		if num[1] == 'N' && !f.Space && !f.Plus {
+			num = num[1:]
+		}
+		f.pad(num)
+		f.Zero = oldZero
+		return
+	}
+	// The sharp flag forces printing a decimal point for non-binary formats
+	// and retains trailing zeros, which we may need to restore.
+	if f.Sharp && verb != 'b' {
+		digits := 0
+		switch verb {
+		case 'v', 'g', 'G':
+			digits = prec
+			// If no precision is set explicitly use a precision of 6.
+			if digits == -1 {
+				digits = 6
+			}
+		}
+
+		// Buffer pre-allocated with enough room for
+		// exponent notations of the form "e+123".
+		var tailBuf [5]byte
+		tail := tailBuf[:0]
+
+		hasDecimalPoint := false
+		// Starting from i = 1 to skip sign at num[0].
+		for i := 1; i < len(num); i++ {
+			switch num[i] {
+			case '.':
+				hasDecimalPoint = true
+			case 'e', 'E':
+				tail = append(tail, num[i:]...)
+				num = num[:i]
+			default:
+				digits--
+			}
+		}
+		if !hasDecimalPoint {
+			num = append(num, '.')
+		}
+		for digits > 0 {
+			num = append(num, '0')
+			digits--
+		}
+		num = append(num, tail...)
+	}
+	// We want a sign if asked for and if the sign is not positive.
+	if f.Plus || num[0] != '+' {
+		// If we're zero padding to the left we want the sign before the leading zeros.
+		// Achieve this by writing the sign out and then padding the unsigned number.
+		if f.Zero && f.WidthPresent && f.Width > len(num) {
+			f.buf.WriteByte(num[0])
+			f.writePadding(f.Width - len(num))
+			f.buf.Write(num[1:])
+			return
+		}
+		f.pad(num)
+		return
+	}
+	// No sign to show and the number is positive; just print the unsigned number.
+	f.pad(num[1:])
+}

vendor/golang.org/x/text/message/message.go

@@ -0,0 +1,186 @@
+// Copyright 2015 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 message // import "golang.org/x/text/message"
+
+import (
+	"io"
+	"os"
+
+	// Include features to facilitate generated catalogs.
+	_ "golang.org/x/text/feature/plural"
+
+	"golang.org/x/text/internal/number"
+	"golang.org/x/text/language"
+	"golang.org/x/text/message/catalog"
+)
+
+// A Printer implements language-specific formatted I/O analogous to the fmt
+// package.
+type Printer struct {
+	// the language
+	tag language.Tag
+
+	toDecimal    number.Formatter
+	toScientific number.Formatter
+
+	cat catalog.Catalog
+}
+
+type options struct {
+	cat catalog.Catalog
+	// TODO:
+	// - allow %s to print integers in written form (tables are likely too large
+	//   to enable this by default).
+	// - list behavior
+	//
+}
+
+// An Option defines an option of a Printer.
+type Option func(o *options)
+
+// Catalog defines the catalog to be used.
+func Catalog(c catalog.Catalog) Option {
+	return func(o *options) { o.cat = c }
+}
+
+// NewPrinter returns a Printer that formats messages tailored to language t.
+func NewPrinter(t language.Tag, opts ...Option) *Printer {
+	options := &options{
+		cat: DefaultCatalog,
+	}
+	for _, o := range opts {
+		o(options)
+	}
+	p := &Printer{
+		tag: t,
+		cat: options.cat,
+	}
+	p.toDecimal.InitDecimal(t)
+	p.toScientific.InitScientific(t)
+	return p
+}
+
+// Sprint is like fmt.Sprint, but using language-specific formatting.
+func (p *Printer) Sprint(a ...interface{}) string {
+	pp := newPrinter(p)
+	pp.doPrint(a)
+	s := pp.String()
+	pp.free()
+	return s
+}
+
+// Fprint is like fmt.Fprint, but using language-specific formatting.
+func (p *Printer) Fprint(w io.Writer, a ...interface{}) (n int, err error) {
+	pp := newPrinter(p)
+	pp.doPrint(a)
+	n64, err := io.Copy(w, &pp.Buffer)
+	pp.free()
+	return int(n64), err
+}
+
+// Print is like fmt.Print, but using language-specific formatting.
+func (p *Printer) Print(a ...interface{}) (n int, err error) {
+	return p.Fprint(os.Stdout, a...)
+}
+
+// Sprintln is like fmt.Sprintln, but using language-specific formatting.
+func (p *Printer) Sprintln(a ...interface{}) string {
+	pp := newPrinter(p)
+	pp.doPrintln(a)
+	s := pp.String()
+	pp.free()
+	return s
+}
+
+// Fprintln is like fmt.Fprintln, but using language-specific formatting.
+func (p *Printer) Fprintln(w io.Writer, a ...interface{}) (n int, err error) {
+	pp := newPrinter(p)
+	pp.doPrintln(a)
+	n64, err := io.Copy(w, &pp.Buffer)
+	pp.free()
+	return int(n64), err
+}
+
+// Println is like fmt.Println, but using language-specific formatting.
+func (p *Printer) Println(a ...interface{}) (n int, err error) {
+	return p.Fprintln(os.Stdout, a...)
+}
+
+// Sprintf is like fmt.Sprintf, but using language-specific formatting.
+func (p *Printer) Sprintf(key Reference, a ...interface{}) string {
+	pp := newPrinter(p)
+	lookupAndFormat(pp, key, a)
+	s := pp.String()
+	pp.free()
+	return s
+}
+
+// Fprintf is like fmt.Fprintf, but using language-specific formatting.
+func (p *Printer) Fprintf(w io.Writer, key Reference, a ...interface{}) (n int, err error) {
+	pp := newPrinter(p)
+	lookupAndFormat(pp, key, a)
+	n, err = w.Write(pp.Bytes())
+	pp.free()
+	return n, err
+
+}
+
+// Printf is like fmt.Printf, but using language-specific formatting.
+func (p *Printer) Printf(key Reference, a ...interface{}) (n int, err error) {
+	pp := newPrinter(p)
+	lookupAndFormat(pp, key, a)
+	n, err = os.Stdout.Write(pp.Bytes())
+	pp.free()
+	return n, err
+}
+
+func lookupAndFormat(p *printer, r Reference, a []interface{}) {
+	p.fmt.Reset(a)
+	var id, msg string
+	switch v := r.(type) {
+	case string:
+		id, msg = v, v
+	case key:
+		id, msg = v.id, v.fallback
+	default:
+		panic("key argument is not a Reference")
+	}
+
+	if p.catContext.Execute(id) == catalog.ErrNotFound {
+		if p.catContext.Execute(msg) == catalog.ErrNotFound {
+			p.Render(msg)
+			return
+		}
+	}
+}
+
+// Arg implements catmsg.Renderer.
+func (p *printer) Arg(i int) interface{} { // TODO, also return "ok" bool
+	i--
+	if uint(i) < uint(len(p.fmt.Args)) {
+		return p.fmt.Args[i]
+	}
+	return nil
+}
+
+// Render implements catmsg.Renderer.
+func (p *printer) Render(msg string) {
+	p.doPrintf(msg)
+}
+
+// A Reference is a string or a message reference.
+type Reference interface {
+	// TODO: also allow []string
+}
+
+// Key creates a message Reference for a message where the given id is used for
+// message lookup and the fallback is returned when no matches are found.
+func Key(id string, fallback string) Reference {
+	return key{id, fallback}
+}
+
+type key struct {
+	id, fallback string
+}

vendor/golang.org/x/text/message/message_test.go

@@ -0,0 +1,181 @@
+// Copyright 2015 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 message
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"testing"
+
+	"golang.org/x/text/internal"
+	"golang.org/x/text/internal/format"
+	"golang.org/x/text/language"
+	"golang.org/x/text/message/catalog"
+)
+
+type formatFunc func(s fmt.State, v rune)
+
+func (f formatFunc) Format(s fmt.State, v rune) { f(s, v) }
+
+func TestBinding(t *testing.T) {
+	testCases := []struct {
+		tag   string
+		value interface{}
+		want  string
+	}{
+		{"en", 1, "1"},
+		{"en", "2", "2"},
+		{ // Language is passed.
+			"en",
+			formatFunc(func(fs fmt.State, v rune) {
+				s := fs.(format.State)
+				io.WriteString(s, s.Language().String())
+			}),
+			"en",
+		},
+	}
+	for i, tc := range testCases {
+		p := NewPrinter(language.MustParse(tc.tag))
+		if got := p.Sprint(tc.value); got != tc.want {
+			t.Errorf("%d:%s:Sprint(%v) = %q; want %q", i, tc.tag, tc.value, got, tc.want)
+		}
+		var buf bytes.Buffer
+		p.Fprint(&buf, tc.value)
+		if got := buf.String(); got != tc.want {
+			t.Errorf("%d:%s:Fprint(%v) = %q; want %q", i, tc.tag, tc.value, got, tc.want)
+		}
+	}
+}
+
+func TestLocalization(t *testing.T) {
+	type test struct {
+		tag  string
+		key  Reference
+		args []interface{}
+		want string
+	}
+	args := func(x ...interface{}) []interface{} { return x }
+	empty := []interface{}{}
+	joe := []interface{}{"Joe"}
+	joeAndMary := []interface{}{"Joe", "Mary"}
+
+	testCases := []struct {
+		desc string
+		cat  []entry
+		test []test
+	}{{
+		desc: "empty",
+		test: []test{
+			{"en", "key", empty, "key"},
+			{"en", "", empty, ""},
+			{"nl", "", empty, ""},
+		},
+	}, {
+		desc: "hierarchical languages",
+		cat: []entry{
+			{"en", "hello %s", "Hello %s!"},
+			{"en-GB", "hello %s", "Hellø %s!"},
+			{"en-US", "hello %s", "Howdy %s!"},
+			{"en", "greetings %s and %s", "Greetings %s and %s!"},
+		},
+		test: []test{
+			{"und", "hello %s", joe, "hello Joe"},
+			{"nl", "hello %s", joe, "hello Joe"},
+			{"en", "hello %s", joe, "Hello Joe!"},
+			{"en-US", "hello %s", joe, "Howdy Joe!"},
+			{"en-GB", "hello %s", joe, "Hellø Joe!"},
+			{"en-oxendict", "hello %s", joe, "Hello Joe!"},
+			{"en-US-oxendict-u-ms-metric", "hello %s", joe, "Howdy Joe!"},
+
+			{"und", "greetings %s and %s", joeAndMary, "greetings Joe and Mary"},
+			{"nl", "greetings %s and %s", joeAndMary, "greetings Joe and Mary"},
+			{"en", "greetings %s and %s", joeAndMary, "Greetings Joe and Mary!"},
+			{"en-US", "greetings %s and %s", joeAndMary, "Greetings Joe and Mary!"},
+			{"en-GB", "greetings %s and %s", joeAndMary, "Greetings Joe and Mary!"},
+			{"en-oxendict", "greetings %s and %s", joeAndMary, "Greetings Joe and Mary!"},
+			{"en-US-oxendict-u-ms-metric", "greetings %s and %s", joeAndMary, "Greetings Joe and Mary!"},
+		},
+	}, {
+		desc: "references",
+		cat: []entry{
+			{"en", "hello", "Hello!"},
+		},
+		test: []test{
+			{"en", "hello", empty, "Hello!"},
+			{"en", Key("hello", "fallback"), empty, "Hello!"},
+			{"en", Key("xxx", "fallback"), empty, "fallback"},
+			{"und", Key("hello", "fallback"), empty, "fallback"},
+		},
+	}, {
+		desc: "zero substitution", // work around limitation of fmt
+		cat: []entry{
+			{"en", "hello %s", "Hello!"},
+			{"en", "hi %s and %s", "Hello %[2]s!"},
+		},
+		test: []test{
+			{"en", "hello %s", joe, "Hello!"},
+			{"en", "hello %s", joeAndMary, "Hello!"},
+			{"en", "hi %s and %s", joeAndMary, "Hello Mary!"},
+			// The following tests resolve to the fallback string.
+			{"und", "hello", joeAndMary, "hello"},
+			{"und", "hello %%%%", joeAndMary, "hello %%"},
+			{"und", "hello %#%%4.2%  ", joeAndMary, "hello %%  "},
+			{"und", "hello %s", joeAndMary, "hello Joe%!(EXTRA string=Mary)"},
+			{"und", "hello %+%%s", joeAndMary, "hello %Joe%!(EXTRA string=Mary)"},
+			{"und", "hello %-42%%s ", joeAndMary, "hello %Joe %!(EXTRA string=Mary)"},
+		},
+	}, {
+		desc: "number formatting", // work around limitation of fmt
+		cat: []entry{
+			{"und", "files", "%d files left"},
+			{"und", "meters", "%.2f meters"},
+			{"de", "files", "%d Dateien übrig"},
+		},
+		test: []test{
+			{"en", "meters", args(3000.2), "3,000.20 meters"},
+			{"en-u-nu-gujr", "files", args(123456), "૧૨૩,૪૫૬ files left"},
+			{"de", "files", args(1234), "1.234 Dateien übrig"},
+			{"de-CH", "files", args(1234), "1’234 Dateien übrig"},
+			{"de-CH-u-nu-mong", "files", args(1234), "᠑’᠒᠓᠔ Dateien übrig"},
+		},
+	}}
+
+	for _, tc := range testCases {
+		cat, _ := initCat(tc.cat)
+
+		for i, pt := range tc.test {
+			t.Run(fmt.Sprintf("%s:%d", tc.desc, i), func(t *testing.T) {
+				p := NewPrinter(language.MustParse(pt.tag), Catalog(cat))
+
+				if got := p.Sprintf(pt.key, pt.args...); got != pt.want {
+					t.Errorf("Sprintf(%q, %v) = %s; want %s",
+						pt.key, pt.args, got, pt.want)
+					return // Next error will likely be the same.
+				}
+
+				w := &bytes.Buffer{}
+				p.Fprintf(w, pt.key, pt.args...)
+				if got := w.String(); got != pt.want {
+					t.Errorf("Fprintf(%q, %v) = %s; want %s",
+						pt.key, pt.args, got, pt.want)
+				}
+			})
+		}
+	}
+}
+
+type entry struct{ tag, key, msg string }
+
+func initCat(entries []entry) (*catalog.Builder, []language.Tag) {
+	tags := []language.Tag{}
+	cat := catalog.NewBuilder()
+	for _, e := range entries {
+		tag := language.MustParse(e.tag)
+		tags = append(tags, tag)
+		cat.SetString(tag, e.key, e.msg)
+	}
+	return cat, internal.UniqueTags(tags)
+}

vendor/golang.org/x/text/message/pipeline/extract.go

@@ -0,0 +1,305 @@
+// 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 pipeline
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/constant"
+	"go/format"
+	"go/token"
+	"go/types"
+	"path"
+	"path/filepath"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	fmtparser "golang.org/x/text/internal/format"
+	"golang.org/x/tools/go/loader"
+)
+
+// TODO:
+// - merge information into existing files
+// - handle different file formats (PO, XLIFF)
+// - handle features (gender, plural)
+// - message rewriting
+
+// Extract extracts all strings form the package defined in Config.
+func Extract(c *Config) (*Locale, error) {
+	conf := loader.Config{}
+	prog, err := loadPackages(&conf, c.Packages)
+	if err != nil {
+		return nil, 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
+			})
+		}
+	}
+
+	out := &Locale{
+		Language: c.SourceLanguage,
+		Messages: messages,
+	}
+	return out, 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
+}

vendor/golang.org/x/text/message/pipeline/generate.go

@@ -0,0 +1,251 @@
+// 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 pipeline
+
+import (
+	"fmt"
+	"io"
+	"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"
+)
+
+var transRe = regexp.MustCompile(`messages\.(.*)\.json`)
+
+// Generate writes a Go file with the given package name to w, which defines a
+// Catalog with translated messages.
+func Generate(w io.Writer, pkg string, extracted *Locale, trans ...*Locale) (n int, err error) {
+	// 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.
+	translations := map[language.Tag]map[string]Message{}
+	languages := []language.Tag{}
+	langVars := []string{}
+	usedKeys := map[string]int{}
+
+	for _, loc := range trans {
+		tag := loc.Language
+		if _, ok := translations[tag]; !ok {
+			translations[tag] = map[string]Message{}
+			languages = append(languages, tag)
+		}
+		for _, m := range loc.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
+				}
+			}
+		}
+	}
+
+	// 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)
+			}
+		}
+	}
+
+	cw := gen.NewCodeWriter()
+
+	x := &struct {
+		Fallback  language.Tag
+		Languages []string
+	}{
+		Fallback:  extracted.Language,
+		Languages: langVars,
+	}
+
+	if err := lookup.Execute(cw, x); err != nil {
+		return 0, wrap(err, "error")
+	}
+
+	keyToIndex := []string{}
+	for k := range usedKeys {
+		keyToIndex = append(keyToIndex, k)
+	}
+	sort.Strings(keyToIndex)
+	fmt.Fprint(cw, "var messageKeyToIndex = map[string]int{\n")
+	for _, k := range keyToIndex {
+		fmt.Fprintf(cw, "%q: %d,\n", k, usedKeys[k])
+	}
+	fmt.Fprint(cw, "}\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 0, wrap(err, "error")
+					}
+					// TODO: support macros.
+					data, err := catmsg.Compile(tag, nil, m)
+					if err != nil {
+						return 0, 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))
+		}
+
+		cw.WriteVar(langVars[i]+"Index", index)
+		cw.WriteConst(langVars[i]+"Data", strings.Join(a, ""))
+	}
+	return cw.WriteGo(w, pkg, "")
+}
+
+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
+}
+
+`))

vendor/golang.org/x/text/message/pipeline/message.go

@@ -0,0 +1,241 @@
+// 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 pipeline
+
+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.
+
+// Config contains configuration for the translation pipeline.
+type Config struct {
+	SourceLanguage language.Tag
+
+	// Supported indicates the languages for which data should be generated.
+	// If unspecified, it will attempt to derive the set of supported languages
+	// from the context.
+	Supported []language.Tag
+
+	Packages []string
+
+	// TODO:
+	// - Printf-style configuration
+	// - Template-style configuration
+	// - Extraction options
+	// - Rewrite options
+	// - Generation options
+}
+
+// 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"`
+// }

vendor/golang.org/x/text/message/pipeline/pipeline.go

@@ -0,0 +1,57 @@
+// 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 pipeline provides tools for creating translation pipelines.
+//
+// NOTE: UNDER DEVELOPMENT. API MAY CHANGE.
+package pipeline
+
+import (
+	"fmt"
+	"go/build"
+	"go/parser"
+	"log"
+
+	"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
+)
+
+// TODO: don't log.
+func logf(format string, args ...interface{}) {
+	log.Printf(format, args...)
+}
+
+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()
+}

vendor/golang.org/x/text/message/pipeline/rewrite.go

@@ -0,0 +1,268 @@
+// 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 pipeline
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/constant"
+	"go/format"
+	"go/token"
+	"io"
+	"os"
+	"strings"
+
+	"golang.org/x/tools/go/loader"
+)
+
+const printerType = "golang.org/x/text/message.Printer"
+
+// Rewrite rewrites the Go files in a single package to use the localization
+// machinery and rewrites strings to adopt best practices when possible.
+// If w is not nil the generated files are written to it, each files with a
+// "--- <filename>" header. Otherwise the files are overwritten.
+func Rewrite(w io.Writer, goPackage string) error {
+	conf := &loader.Config{
+		AllowErrors: true, // Allow unused instances of message.Printer.
+	}
+	prog, err := loadPackages(conf, []string{goPackage})
+	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 := w
+			if w == nil {
+				var err error
+				if w, err = os.Create(conf.Fset.File(f.Pos()).Name()); err != nil {
+					return wrap(err, "open failed")
+				}
+			} else {
+				fmt.Fprintln(w, "---", conf.Fset.File(f.Pos()).Name())
+			}
+
+			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
+}

vendor/golang.org/x/text/message/print.go

@@ -0,0 +1,979 @@
+// 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 message
+
+import (
+	"bytes"
+	"fmt" // TODO: consider copying interfaces from package fmt to avoid dependency.
+	"math"
+	"reflect"
+	"sync"
+	"unicode/utf8"
+
+	"golang.org/x/text/internal/format"
+	"golang.org/x/text/internal/number"
+	"golang.org/x/text/language"
+	"golang.org/x/text/message/catalog"
+)
+
+// Strings for use with buffer.WriteString.
+// This is less overhead than using buffer.Write with byte arrays.
+const (
+	commaSpaceString  = ", "
+	nilAngleString    = "<nil>"
+	nilParenString    = "(nil)"
+	nilString         = "nil"
+	mapString         = "map["
+	percentBangString = "%!"
+	missingString     = "(MISSING)"
+	badIndexString    = "(BADINDEX)"
+	panicString       = "(PANIC="
+	extraString       = "%!(EXTRA "
+	badWidthString    = "%!(BADWIDTH)"
+	badPrecString     = "%!(BADPREC)"
+	noVerbString      = "%!(NOVERB)"
+
+	invReflectString = "<invalid reflect.Value>"
+)
+
+var printerPool = sync.Pool{
+	New: func() interface{} { return new(printer) },
+}
+
+// newPrinter allocates a new printer struct or grabs a cached one.
+func newPrinter(pp *Printer) *printer {
+	p := printerPool.Get().(*printer)
+	p.Printer = *pp
+	// TODO: cache most of the following call.
+	p.catContext = pp.cat.Context(pp.tag, p)
+
+	p.panicking = false
+	p.erroring = false
+	p.fmt.init(&p.Buffer)
+	return p
+}
+
+// free saves used printer structs in printerFree; avoids an allocation per invocation.
+func (p *printer) free() {
+	p.Buffer.Reset()
+	p.arg = nil
+	p.value = reflect.Value{}
+	printerPool.Put(p)
+}
+
+// printer is used to store a printer's state.
+// It implements "golang.org/x/text/internal/format".State.
+type printer struct {
+	Printer
+
+	// the context for looking up message translations
+	catContext *catalog.Context
+
+	// buffer for accumulating output.
+	bytes.Buffer
+
+	// arg holds the current item, as an interface{}.
+	arg interface{}
+	// value is used instead of arg for reflect values.
+	value reflect.Value
+
+	// fmt is used to format basic items such as integers or strings.
+	fmt formatInfo
+
+	// panicking is set by catchPanic to avoid infinite panic, recover, panic, ... recursion.
+	panicking bool
+	// erroring is set when printing an error string to guard against calling handleMethods.
+	erroring bool
+}
+
+// Language implements "golang.org/x/text/internal/format".State.
+func (p *printer) Language() language.Tag { return p.tag }
+
+func (p *printer) Width() (wid int, ok bool) { return p.fmt.Width, p.fmt.WidthPresent }
+
+func (p *printer) Precision() (prec int, ok bool) { return p.fmt.Prec, p.fmt.PrecPresent }
+
+func (p *printer) Flag(b int) bool {
+	switch b {
+	case '-':
+		return p.fmt.Minus
+	case '+':
+		return p.fmt.Plus || p.fmt.PlusV
+	case '#':
+		return p.fmt.Sharp || p.fmt.SharpV
+	case ' ':
+		return p.fmt.Space
+	case '0':
+		return p.fmt.Zero
+	}
+	return false
+}
+
+// getField gets the i'th field of the struct value.
+// If the field is itself is an interface, return a value for
+// the thing inside the interface, not the interface itself.
+func getField(v reflect.Value, i int) reflect.Value {
+	val := v.Field(i)
+	if val.Kind() == reflect.Interface && !val.IsNil() {
+		val = val.Elem()
+	}
+	return val
+}
+
+func (p *printer) unknownType(v reflect.Value) {
+	if !v.IsValid() {
+		p.WriteString(nilAngleString)
+		return
+	}
+	p.WriteByte('?')
+	p.WriteString(v.Type().String())
+	p.WriteByte('?')
+}
+
+func (p *printer) badVerb(verb rune) {
+	p.erroring = true
+	p.WriteString(percentBangString)
+	p.WriteRune(verb)
+	p.WriteByte('(')
+	switch {
+	case p.arg != nil:
+		p.WriteString(reflect.TypeOf(p.arg).String())
+		p.WriteByte('=')
+		p.printArg(p.arg, 'v')
+	case p.value.IsValid():
+		p.WriteString(p.value.Type().String())
+		p.WriteByte('=')
+		p.printValue(p.value, 'v', 0)
+	default:
+		p.WriteString(nilAngleString)
+	}
+	p.WriteByte(')')
+	p.erroring = false
+}
+
+func (p *printer) fmtBool(v bool, verb rune) {
+	switch verb {
+	case 't', 'v':
+		p.fmt.fmt_boolean(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
+// not, as requested, by temporarily setting the sharp flag.
+func (p *printer) fmt0x64(v uint64, leading0x bool) {
+	sharp := p.fmt.Sharp
+	p.fmt.Sharp = leading0x
+	p.fmt.fmt_integer(v, 16, unsigned, ldigits)
+	p.fmt.Sharp = sharp
+}
+
+// fmtInteger formats a signed or unsigned integer.
+func (p *printer) fmtInteger(v uint64, isSigned bool, verb rune) {
+	switch verb {
+	case 'v':
+		if p.fmt.SharpV && !isSigned {
+			p.fmt0x64(v, true)
+			return
+		}
+		fallthrough
+	case 'd':
+		if p.fmt.Sharp || p.fmt.SharpV {
+			p.fmt.fmt_integer(v, 10, isSigned, ldigits)
+		} else {
+			p.fmtDecimalInt(v, isSigned)
+		}
+	case 'b':
+		p.fmt.fmt_integer(v, 2, isSigned, ldigits)
+	case 'o':
+		p.fmt.fmt_integer(v, 8, isSigned, ldigits)
+	case 'x':
+		p.fmt.fmt_integer(v, 16, isSigned, ldigits)
+	case 'X':
+		p.fmt.fmt_integer(v, 16, isSigned, udigits)
+	case 'c':
+		p.fmt.fmt_c(v)
+	case 'q':
+		if v <= utf8.MaxRune {
+			p.fmt.fmt_qc(v)
+		} else {
+			p.badVerb(verb)
+		}
+	case 'U':
+		p.fmt.fmt_unicode(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmtFloat formats a float. The default precision for each verb
+// is specified as last argument in the call to fmt_float.
+func (p *printer) fmtFloat(v float64, size int, verb rune) {
+	switch verb {
+	case 'b':
+		p.fmt.fmt_float(v, size, verb, -1)
+	case 'v':
+		verb = 'g'
+		fallthrough
+	case 'g', 'G':
+		if p.fmt.Sharp || p.fmt.SharpV {
+			p.fmt.fmt_float(v, size, verb, -1)
+		} else {
+			p.fmtVariableFloat(v, size)
+		}
+	case 'e', 'E':
+		if p.fmt.Sharp || p.fmt.SharpV {
+			p.fmt.fmt_float(v, size, verb, 6)
+		} else {
+			p.fmtScientific(v, size, 6)
+		}
+	case 'f', 'F':
+		if p.fmt.Sharp || p.fmt.SharpV {
+			p.fmt.fmt_float(v, size, verb, 6)
+		} else {
+			p.fmtDecimalFloat(v, size, 6)
+		}
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *printer) setFlags(f *number.Formatter) {
+	f.Flags &^= number.ElideSign
+	if p.fmt.Plus || p.fmt.Space {
+		f.Flags |= number.AlwaysSign
+		if !p.fmt.Plus {
+			f.Flags |= number.ElideSign
+		}
+	} else {
+		f.Flags &^= number.AlwaysSign
+	}
+}
+
+func (p *printer) updatePadding(f *number.Formatter) {
+	f.Flags &^= number.PadMask
+	if p.fmt.Minus {
+		f.Flags |= number.PadAfterSuffix
+	} else {
+		f.Flags |= number.PadBeforePrefix
+	}
+	f.PadRune = ' '
+	f.FormatWidth = uint16(p.fmt.Width)
+}
+
+func (p *printer) initDecimal(minFrac, maxFrac int) {
+	f := &p.toDecimal
+	f.MinIntegerDigits = 1
+	f.MaxIntegerDigits = 0
+	f.MinFractionDigits = uint8(minFrac)
+	f.MaxFractionDigits = int16(maxFrac)
+	p.setFlags(f)
+	f.PadRune = 0
+	if p.fmt.WidthPresent {
+		if p.fmt.Zero {
+			wid := p.fmt.Width
+			// Use significant integers for this.
+			// TODO: this is not the same as width, but so be it.
+			if f.MinFractionDigits > 0 {
+				wid -= 1 + int(f.MinFractionDigits)
+			}
+			if p.fmt.Plus || p.fmt.Space {
+				wid--
+			}
+			if wid > 0 && wid > int(f.MinIntegerDigits) {
+				f.MinIntegerDigits = uint8(wid)
+			}
+		}
+		p.updatePadding(f)
+	}
+}
+
+func (p *printer) initScientific(minFrac, maxFrac int) {
+	f := &p.toScientific
+	if maxFrac < 0 {
+		f.SetPrecision(maxFrac)
+	} else {
+		f.SetPrecision(maxFrac + 1)
+		f.MinFractionDigits = uint8(minFrac)
+		f.MaxFractionDigits = int16(maxFrac)
+	}
+	f.MinExponentDigits = 2
+	p.setFlags(f)
+	f.PadRune = 0
+	if p.fmt.WidthPresent {
+		f.Flags &^= number.PadMask
+		if p.fmt.Zero {
+			f.PadRune = f.Digit(0)
+			f.Flags |= number.PadAfterPrefix
+		} else {
+			f.PadRune = ' '
+			f.Flags |= number.PadBeforePrefix
+		}
+		p.updatePadding(f)
+	}
+}
+
+func (p *printer) fmtDecimalInt(v uint64, isSigned bool) {
+	var d number.Decimal
+
+	f := &p.toDecimal
+	if p.fmt.PrecPresent {
+		p.setFlags(f)
+		f.MinIntegerDigits = uint8(p.fmt.Prec)
+		f.MaxIntegerDigits = 0
+		f.MinFractionDigits = 0
+		f.MaxFractionDigits = 0
+		if p.fmt.WidthPresent {
+			p.updatePadding(f)
+		}
+	} else {
+		p.initDecimal(0, 0)
+	}
+	d.ConvertInt(p.toDecimal.RoundingContext, isSigned, v)
+
+	out := p.toDecimal.Format([]byte(nil), &d)
+	p.Buffer.Write(out)
+}
+
+func (p *printer) fmtDecimalFloat(v float64, size, prec int) {
+	var d number.Decimal
+	if p.fmt.PrecPresent {
+		prec = p.fmt.Prec
+	}
+	p.initDecimal(prec, prec)
+	d.ConvertFloat(p.toDecimal.RoundingContext, v, size)
+
+	out := p.toDecimal.Format([]byte(nil), &d)
+	p.Buffer.Write(out)
+}
+
+func (p *printer) fmtVariableFloat(v float64, size int) {
+	prec := -1
+	if p.fmt.PrecPresent {
+		prec = p.fmt.Prec
+	}
+	var d number.Decimal
+	p.initScientific(0, prec)
+	d.ConvertFloat(p.toScientific.RoundingContext, v, size)
+
+	// Copy logic of 'g' formatting from strconv. It is simplified a bit as
+	// we don't have to mind having prec > len(d.Digits).
+	shortest := prec < 0
+	ePrec := prec
+	if shortest {
+		prec = len(d.Digits)
+		ePrec = 6
+	} else if prec == 0 {
+		prec = 1
+		ePrec = 1
+	}
+	exp := int(d.Exp) - 1
+	if exp < -4 || exp >= ePrec {
+		p.initScientific(0, prec)
+
+		out := p.toScientific.Format([]byte(nil), &d)
+		p.Buffer.Write(out)
+	} else {
+		if prec > int(d.Exp) {
+			prec = len(d.Digits)
+		}
+		if prec -= int(d.Exp); prec < 0 {
+			prec = 0
+		}
+		p.initDecimal(0, prec)
+
+		out := p.toDecimal.Format([]byte(nil), &d)
+		p.Buffer.Write(out)
+	}
+}
+
+func (p *printer) fmtScientific(v float64, size, prec int) {
+	var d number.Decimal
+	if p.fmt.PrecPresent {
+		prec = p.fmt.Prec
+	}
+	p.initScientific(prec, prec)
+	rc := p.toScientific.RoundingContext
+	d.ConvertFloat(rc, v, size)
+
+	out := p.toScientific.Format([]byte(nil), &d)
+	p.Buffer.Write(out)
+
+}
+
+// fmtComplex formats a complex number v with
+// r = real(v) and j = imag(v) as (r+ji) using
+// fmtFloat for r and j formatting.
+func (p *printer) fmtComplex(v complex128, size int, verb rune) {
+	// Make sure any unsupported verbs are found before the
+	// calls to fmtFloat to not generate an incorrect error string.
+	switch verb {
+	case 'v', 'b', 'g', 'G', 'f', 'F', 'e', 'E':
+		p.WriteByte('(')
+		p.fmtFloat(real(v), size/2, verb)
+		// Imaginary part always has a sign.
+		if math.IsNaN(imag(v)) {
+			// By CLDR's rules, NaNs do not use patterns or signs. As this code
+			// relies on AlwaysSign working for imaginary parts, we need to
+			// manually handle NaNs.
+			f := &p.toScientific
+			p.setFlags(f)
+			p.updatePadding(f)
+			p.setFlags(f)
+			nan := f.Symbol(number.SymNan)
+			extra := 0
+			if w, ok := p.Width(); ok {
+				extra = w - utf8.RuneCountInString(nan) - 1
+			}
+			if f.Flags&number.PadAfterNumber == 0 {
+				for ; extra > 0; extra-- {
+					p.WriteRune(f.PadRune)
+				}
+			}
+			p.WriteString(f.Symbol(number.SymPlusSign))
+			p.WriteString(nan)
+			for ; extra > 0; extra-- {
+				p.WriteRune(f.PadRune)
+			}
+			p.WriteString("i)")
+			return
+		}
+		oldPlus := p.fmt.Plus
+		p.fmt.Plus = true
+		p.fmtFloat(imag(v), size/2, verb)
+		p.WriteString("i)") // TODO: use symbol?
+		p.fmt.Plus = oldPlus
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *printer) fmtString(v string, verb rune) {
+	switch verb {
+	case 'v':
+		if p.fmt.SharpV {
+			p.fmt.fmt_q(v)
+		} else {
+			p.fmt.fmt_s(v)
+		}
+	case 's':
+		p.fmt.fmt_s(v)
+	case 'x':
+		p.fmt.fmt_sx(v, ldigits)
+	case 'X':
+		p.fmt.fmt_sx(v, udigits)
+	case 'q':
+		p.fmt.fmt_q(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *printer) fmtBytes(v []byte, verb rune, typeString string) {
+	switch verb {
+	case 'v', 'd':
+		if p.fmt.SharpV {
+			p.WriteString(typeString)
+			if v == nil {
+				p.WriteString(nilParenString)
+				return
+			}
+			p.WriteByte('{')
+			for i, c := range v {
+				if i > 0 {
+					p.WriteString(commaSpaceString)
+				}
+				p.fmt0x64(uint64(c), true)
+			}
+			p.WriteByte('}')
+		} else {
+			p.WriteByte('[')
+			for i, c := range v {
+				if i > 0 {
+					p.WriteByte(' ')
+				}
+				p.fmt.fmt_integer(uint64(c), 10, unsigned, ldigits)
+			}
+			p.WriteByte(']')
+		}
+	case 's':
+		p.fmt.fmt_s(string(v))
+	case 'x':
+		p.fmt.fmt_bx(v, ldigits)
+	case 'X':
+		p.fmt.fmt_bx(v, udigits)
+	case 'q':
+		p.fmt.fmt_q(string(v))
+	default:
+		p.printValue(reflect.ValueOf(v), verb, 0)
+	}
+}
+
+func (p *printer) fmtPointer(value reflect.Value, verb rune) {
+	var u uintptr
+	switch value.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr, reflect.Slice, reflect.UnsafePointer:
+		u = value.Pointer()
+	default:
+		p.badVerb(verb)
+		return
+	}
+
+	switch verb {
+	case 'v':
+		if p.fmt.SharpV {
+			p.WriteByte('(')
+			p.WriteString(value.Type().String())
+			p.WriteString(")(")
+			if u == 0 {
+				p.WriteString(nilString)
+			} else {
+				p.fmt0x64(uint64(u), true)
+			}
+			p.WriteByte(')')
+		} else {
+			if u == 0 {
+				p.fmt.padString(nilAngleString)
+			} else {
+				p.fmt0x64(uint64(u), !p.fmt.Sharp)
+			}
+		}
+	case 'p':
+		p.fmt0x64(uint64(u), !p.fmt.Sharp)
+	case 'b', 'o', 'd', 'x', 'X':
+		if verb == 'd' {
+			p.fmt.Sharp = true // Print as standard go. TODO: does this make sense?
+		}
+		p.fmtInteger(uint64(u), unsigned, verb)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *printer) catchPanic(arg interface{}, verb rune) {
+	if err := recover(); err != nil {
+		// If it's a nil pointer, just say "<nil>". The likeliest causes are a
+		// Stringer that fails to guard against nil or a nil pointer for a
+		// value receiver, and in either case, "<nil>" is a nice result.
+		if v := reflect.ValueOf(arg); v.Kind() == reflect.Ptr && v.IsNil() {
+			p.WriteString(nilAngleString)
+			return
+		}
+		// Otherwise print a concise panic message. Most of the time the panic
+		// value will print itself nicely.
+		if p.panicking {
+			// Nested panics; the recursion in printArg cannot succeed.
+			panic(err)
+		}
+
+		oldFlags := p.fmt.Parser
+		// For this output we want default behavior.
+		p.fmt.ClearFlags()
+
+		p.WriteString(percentBangString)
+		p.WriteRune(verb)
+		p.WriteString(panicString)
+		p.panicking = true
+		p.printArg(err, 'v')
+		p.panicking = false
+		p.WriteByte(')')
+
+		p.fmt.Parser = oldFlags
+	}
+}
+
+func (p *printer) handleMethods(verb rune) (handled bool) {
+	if p.erroring {
+		return
+	}
+	// Is it a Formatter?
+	if formatter, ok := p.arg.(format.Formatter); ok {
+		handled = true
+		defer p.catchPanic(p.arg, verb)
+		formatter.Format(p, verb)
+		return
+	}
+	if formatter, ok := p.arg.(fmt.Formatter); ok {
+		handled = true
+		defer p.catchPanic(p.arg, verb)
+		formatter.Format(p, verb)
+		return
+	}
+
+	// If we're doing Go syntax and the argument knows how to supply it, take care of it now.
+	if p.fmt.SharpV {
+		if stringer, ok := p.arg.(fmt.GoStringer); ok {
+			handled = true
+			defer p.catchPanic(p.arg, verb)
+			// Print the result of GoString unadorned.
+			p.fmt.fmt_s(stringer.GoString())
+			return
+		}
+	} else {
+		// If a string is acceptable according to the format, see if
+		// the value satisfies one of the string-valued interfaces.
+		// Println etc. set verb to %v, which is "stringable".
+		switch verb {
+		case 'v', 's', 'x', 'X', 'q':
+			// Is it an error or Stringer?
+			// The duplication in the bodies is necessary:
+			// setting handled and deferring catchPanic
+			// must happen before calling the method.
+			switch v := p.arg.(type) {
+			case error:
+				handled = true
+				defer p.catchPanic(p.arg, verb)
+				p.fmtString(v.Error(), verb)
+				return
+
+			case fmt.Stringer:
+				handled = true
+				defer p.catchPanic(p.arg, verb)
+				p.fmtString(v.String(), verb)
+				return
+			}
+		}
+	}
+	return false
+}
+
+func (p *printer) printArg(arg interface{}, verb rune) {
+	p.arg = arg
+	p.value = reflect.Value{}
+
+	if arg == nil {
+		switch verb {
+		case 'T', 'v':
+			p.fmt.padString(nilAngleString)
+		default:
+			p.badVerb(verb)
+		}
+		return
+	}
+
+	// Special processing considerations.
+	// %T (the value's type) and %p (its address) are special; we always do them first.
+	switch verb {
+	case 'T':
+		p.fmt.fmt_s(reflect.TypeOf(arg).String())
+		return
+	case 'p':
+		p.fmtPointer(reflect.ValueOf(arg), 'p')
+		return
+	}
+
+	// Some types can be done without reflection.
+	switch f := arg.(type) {
+	case bool:
+		p.fmtBool(f, verb)
+	case float32:
+		p.fmtFloat(float64(f), 32, verb)
+	case float64:
+		p.fmtFloat(f, 64, verb)
+	case complex64:
+		p.fmtComplex(complex128(f), 64, verb)
+	case complex128:
+		p.fmtComplex(f, 128, verb)
+	case int:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int8:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int16:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int32:
+		p.fmtInteger(uint64(f), signed, verb)
+	case int64:
+		p.fmtInteger(uint64(f), signed, verb)
+	case uint:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint8:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint16:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint32:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case uint64:
+		p.fmtInteger(f, unsigned, verb)
+	case uintptr:
+		p.fmtInteger(uint64(f), unsigned, verb)
+	case string:
+		p.fmtString(f, verb)
+	case []byte:
+		p.fmtBytes(f, verb, "[]byte")
+	case reflect.Value:
+		// Handle extractable values with special methods
+		// since printValue does not handle them at depth 0.
+		if f.IsValid() && f.CanInterface() {
+			p.arg = f.Interface()
+			if p.handleMethods(verb) {
+				return
+			}
+		}
+		p.printValue(f, verb, 0)
+	default:
+		// If the type is not simple, it might have methods.
+		if !p.handleMethods(verb) {
+			// Need to use reflection, since the type had no
+			// interface methods that could be used for formatting.
+			p.printValue(reflect.ValueOf(f), verb, 0)
+		}
+	}
+}
+
+// printValue is similar to printArg but starts with a reflect value, not an interface{} value.
+// It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
+func (p *printer) printValue(value reflect.Value, verb rune, depth int) {
+	// Handle values with special methods if not already handled by printArg (depth == 0).
+	if depth > 0 && value.IsValid() && value.CanInterface() {
+		p.arg = value.Interface()
+		if p.handleMethods(verb) {
+			return
+		}
+	}
+	p.arg = nil
+	p.value = value
+
+	switch f := value; value.Kind() {
+	case reflect.Invalid:
+		if depth == 0 {
+			p.WriteString(invReflectString)
+		} else {
+			switch verb {
+			case 'v':
+				p.WriteString(nilAngleString)
+			default:
+				p.badVerb(verb)
+			}
+		}
+	case reflect.Bool:
+		p.fmtBool(f.Bool(), verb)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p.fmtInteger(uint64(f.Int()), signed, verb)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p.fmtInteger(f.Uint(), unsigned, verb)
+	case reflect.Float32:
+		p.fmtFloat(f.Float(), 32, verb)
+	case reflect.Float64:
+		p.fmtFloat(f.Float(), 64, verb)
+	case reflect.Complex64:
+		p.fmtComplex(f.Complex(), 64, verb)
+	case reflect.Complex128:
+		p.fmtComplex(f.Complex(), 128, verb)
+	case reflect.String:
+		p.fmtString(f.String(), verb)
+	case reflect.Map:
+		if p.fmt.SharpV {
+			p.WriteString(f.Type().String())
+			if f.IsNil() {
+				p.WriteString(nilParenString)
+				return
+			}
+			p.WriteByte('{')
+		} else {
+			p.WriteString(mapString)
+		}
+		keys := f.MapKeys()
+		for i, key := range keys {
+			if i > 0 {
+				if p.fmt.SharpV {
+					p.WriteString(commaSpaceString)
+				} else {
+					p.WriteByte(' ')
+				}
+			}
+			p.printValue(key, verb, depth+1)
+			p.WriteByte(':')
+			p.printValue(f.MapIndex(key), verb, depth+1)
+		}
+		if p.fmt.SharpV {
+			p.WriteByte('}')
+		} else {
+			p.WriteByte(']')
+		}
+	case reflect.Struct:
+		if p.fmt.SharpV {
+			p.WriteString(f.Type().String())
+		}
+		p.WriteByte('{')
+		for i := 0; i < f.NumField(); i++ {
+			if i > 0 {
+				if p.fmt.SharpV {
+					p.WriteString(commaSpaceString)
+				} else {
+					p.WriteByte(' ')
+				}
+			}
+			if p.fmt.PlusV || p.fmt.SharpV {
+				if name := f.Type().Field(i).Name; name != "" {
+					p.WriteString(name)
+					p.WriteByte(':')
+				}
+			}
+			p.printValue(getField(f, i), verb, depth+1)
+		}
+		p.WriteByte('}')
+	case reflect.Interface:
+		value := f.Elem()
+		if !value.IsValid() {
+			if p.fmt.SharpV {
+				p.WriteString(f.Type().String())
+				p.WriteString(nilParenString)
+			} else {
+				p.WriteString(nilAngleString)
+			}
+		} else {
+			p.printValue(value, verb, depth+1)
+		}
+	case reflect.Array, reflect.Slice:
+		switch verb {
+		case 's', 'q', 'x', 'X':
+			// Handle byte and uint8 slices and arrays special for the above verbs.
+			t := f.Type()
+			if t.Elem().Kind() == reflect.Uint8 {
+				var bytes []byte
+				if f.Kind() == reflect.Slice {
+					bytes = f.Bytes()
+				} else if f.CanAddr() {
+					bytes = f.Slice(0, f.Len()).Bytes()
+				} else {
+					// We have an array, but we cannot Slice() a non-addressable array,
+					// so we build a slice by hand. This is a rare case but it would be nice
+					// if reflection could help a little more.
+					bytes = make([]byte, f.Len())
+					for i := range bytes {
+						bytes[i] = byte(f.Index(i).Uint())
+					}
+				}
+				p.fmtBytes(bytes, verb, t.String())
+				return
+			}
+		}
+		if p.fmt.SharpV {
+			p.WriteString(f.Type().String())
+			if f.Kind() == reflect.Slice && f.IsNil() {
+				p.WriteString(nilParenString)
+				return
+			}
+			p.WriteByte('{')
+			for i := 0; i < f.Len(); i++ {
+				if i > 0 {
+					p.WriteString(commaSpaceString)
+				}
+				p.printValue(f.Index(i), verb, depth+1)
+			}
+			p.WriteByte('}')
+		} else {
+			p.WriteByte('[')
+			for i := 0; i < f.Len(); i++ {
+				if i > 0 {
+					p.WriteByte(' ')
+				}
+				p.printValue(f.Index(i), verb, depth+1)
+			}
+			p.WriteByte(']')
+		}
+	case reflect.Ptr:
+		// pointer to array or slice or struct?  ok at top level
+		// but not embedded (avoid loops)
+		if depth == 0 && f.Pointer() != 0 {
+			switch a := f.Elem(); a.Kind() {
+			case reflect.Array, reflect.Slice, reflect.Struct, reflect.Map:
+				p.WriteByte('&')
+				p.printValue(a, verb, depth+1)
+				return
+			}
+		}
+		fallthrough
+	case reflect.Chan, reflect.Func, reflect.UnsafePointer:
+		p.fmtPointer(f, verb)
+	default:
+		p.unknownType(f)
+	}
+}
+
+func (p *printer) badArgNum(verb rune) {
+	p.WriteString(percentBangString)
+	p.WriteRune(verb)
+	p.WriteString(badIndexString)
+}
+
+func (p *printer) missingArg(verb rune) {
+	p.WriteString(percentBangString)
+	p.WriteRune(verb)
+	p.WriteString(missingString)
+}
+
+func (p *printer) doPrintf(fmt string) {
+	for p.fmt.Parser.SetFormat(fmt); p.fmt.Scan(); {
+		switch p.fmt.Status {
+		case format.StatusText:
+			p.WriteString(p.fmt.Text())
+		case format.StatusSubstitution:
+			p.printArg(p.Arg(p.fmt.ArgNum), p.fmt.Verb)
+		case format.StatusBadWidthSubstitution:
+			p.WriteString(badWidthString)
+			p.printArg(p.Arg(p.fmt.ArgNum), p.fmt.Verb)
+		case format.StatusBadPrecSubstitution:
+			p.WriteString(badPrecString)
+			p.printArg(p.Arg(p.fmt.ArgNum), p.fmt.Verb)
+		case format.StatusNoVerb:
+			p.WriteString(noVerbString)
+		case format.StatusBadArgNum:
+			p.badArgNum(p.fmt.Verb)
+		case format.StatusMissingArg:
+			p.missingArg(p.fmt.Verb)
+		default:
+			panic("unreachable")
+		}
+	}
+
+	// Check for extra arguments, but only if there was at least one ordered
+	// argument. Note that this behavior is necessarily different from fmt:
+	// different variants of messages may opt to drop some or all of the
+	// arguments.
+	if !p.fmt.Reordered && p.fmt.ArgNum < len(p.fmt.Args) && p.fmt.ArgNum != 0 {
+		p.fmt.ClearFlags()
+		p.WriteString(extraString)
+		for i, arg := range p.fmt.Args[p.fmt.ArgNum:] {
+			if i > 0 {
+				p.WriteString(commaSpaceString)
+			}
+			if arg == nil {
+				p.WriteString(nilAngleString)
+			} else {
+				p.WriteString(reflect.TypeOf(arg).String())
+				p.WriteString("=")
+				p.printArg(arg, 'v')
+			}
+		}
+		p.WriteByte(')')
+	}
+}
+
+func (p *printer) doPrint(a []interface{}) {
+	prevString := false
+	for argNum, arg := range a {
+		isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
+		// Add a space between two non-string arguments.
+		if argNum > 0 && !isString && !prevString {
+			p.WriteByte(' ')
+		}
+		p.printArg(arg, 'v')
+		prevString = isString
+	}
+}
+
+// doPrintln is like doPrint but always adds a space between arguments
+// and a newline after the last argument.
+func (p *printer) doPrintln(a []interface{}) {
+	for argNum, arg := range a {
+		if argNum > 0 {
+			p.WriteByte(' ')
+		}
+		p.printArg(arg, 'v')
+	}
+	p.WriteByte('\n')
+}