langs/i18n: Upgrade to go-i18n v2

Fixes #5242

2 files changed, 70 insertions, 78 deletions

diff --git a/langs/i18n/i18n.go b/langs/i18n/i18n.go
index 5beef8683..922b06367 100644
--- a/langs/i18n/i18n.go
+++ b/langs/i18n/i18n.go
@@ -14,35 +14,40 @@
 package i18n
 
 import (
+	"reflect"
+	"strings"
+
+	"github.com/gohugoio/hugo/common/hreflect"
 	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/config"
 	"github.com/gohugoio/hugo/helpers"
 
-	"github.com/nicksnyder/go-i18n/i18n/bundle"
-	"github.com/nicksnyder/go-i18n/i18n/translation"
+	"github.com/nicksnyder/go-i18n/v2/i18n"
 )
 
+type translateFunc func(translationID string, templateData interface{}) string
+
 var (
 	i18nWarningLogger = helpers.NewDistinctFeedbackLogger()
 )
 
 // Translator handles i18n translations.
 type Translator struct {
-	translateFuncs map[string]bundle.TranslateFunc
+	translateFuncs map[string]translateFunc
 	cfg            config.Provider
 	logger         *loggers.Logger
 }
 
 // NewTranslator creates a new Translator for the given language bundle and configuration.
-func NewTranslator(b *bundle.Bundle, cfg config.Provider, logger *loggers.Logger) Translator {
-	t := Translator{cfg: cfg, logger: logger, translateFuncs: make(map[string]bundle.TranslateFunc)}
+func NewTranslator(b *i18n.Bundle, cfg config.Provider, logger *loggers.Logger) Translator {
+	t := Translator{cfg: cfg, logger: logger, translateFuncs: make(map[string]translateFunc)}
 	t.initFuncs(b)
 	return t
 }
 
 // Func gets the translate func for the given language, or for the default
 // configured language if not found.
-func (t Translator) Func(lang string) bundle.TranslateFunc {
+func (t Translator) Func(lang string) translateFunc {
 	if f, ok := t.translateFuncs[lang]; ok {
 		return f
 	}
@@ -50,68 +55,57 @@ func (t Translator) Func(lang string) bundle.TranslateFunc {
 	if f, ok := t.translateFuncs[t.cfg.GetString("defaultContentLanguage")]; ok {
 		return f
 	}
+
 	t.logger.INFO.Println("i18n not initialized; if you need string translations, check that you have a bundle in /i18n that matches the site language or the default language.")
-	return func(translationID string, args ...interface{}) string {
+	return func(translationID string, args interface{}) string {
 		return ""
 	}
 
 }
 
-func (t Translator) initFuncs(bndl *bundle.Bundle) {
-	defaultContentLanguage := t.cfg.GetString("defaultContentLanguage")
-
-	defaultT, err := bndl.Tfunc(defaultContentLanguage)
-	if err != nil {
-		t.logger.INFO.Printf("No translation bundle found for default language %q", defaultContentLanguage)
-	}
-
-	translations := bndl.Translations()
-
+func (t Translator) initFuncs(bndl *i18n.Bundle) {
 	enableMissingTranslationPlaceholders := t.cfg.GetBool("enableMissingTranslationPlaceholders")
 	for _, lang := range bndl.LanguageTags() {
-		currentLang := lang
 
-		t.translateFuncs[currentLang] = func(translationID string, args ...interface{}) string {
-			tFunc, err := bndl.Tfunc(currentLang)
-			if err != nil {
-				t.logger.WARN.Printf("could not load translations for language %q (%s), will use default content language.\n", lang, err)
+		currentLang := lang
+		currentLangStr := currentLang.String()
+		currentLangKey := strings.TrimPrefix(currentLangStr, artificialLangTagPrefix)
+		localizer := i18n.NewLocalizer(bndl, currentLangStr)
+
+		t.translateFuncs[currentLangKey] = func(translationID string, templateData interface{}) string {
+
+			if templateData != nil {
+				tp := reflect.TypeOf(templateData)
+				if hreflect.IsNumber(tp.Kind()) {
+					// This was how go-i18n worked in v1.
+					templateData = map[string]interface{}{
+						"Count": templateData,
+					}
+				}
 			}
 
-			translated := tFunc(translationID, args...)
-			if translated != translationID {
+			translated, translatedLang, err := localizer.LocalizeWithTag(&i18n.LocalizeConfig{
+				MessageID:    translationID,
+				TemplateData: templateData,
+			})
+
+			if err == nil && currentLang == translatedLang {
 				return translated
 			}
-			// If there is no translation for translationID,
-			// then Tfunc returns translationID itself.
-			// But if user set same translationID and translation, we should check
-			// if it really untranslated:
-			if isIDTranslated(translations, currentLang, translationID) {
-				return translated
+
+			if _, ok := err.(*i18n.MessageNotFoundErr); !ok {
+				t.logger.WARN.Printf("Failed to get translated string for language %q and ID %q: %s", currentLangStr, translationID, err)
 			}
 
 			if t.cfg.GetBool("logI18nWarnings") {
-				i18nWarningLogger.Printf("i18n|MISSING_TRANSLATION|%s|%s", currentLang, translationID)
+				i18nWarningLogger.Printf("i18n|MISSING_TRANSLATION|%s|%s", currentLangStr, translationID)
 			}
+
 			if enableMissingTranslationPlaceholders {
 				return "[i18n] " + translationID
 			}
-			if defaultT != nil {
-				translated := defaultT(translationID, args...)
-				if translated != translationID {
-					return translated
-				}
-				if isIDTranslated(translations, defaultContentLanguage, translationID) {
-					return translated
-				}
-			}
-			return ""
+
+			return translated
 		}
 	}
 }
-
-// If the translation map contains translationID for specified currentLang,
-// then the translationID is actually translated.
-func isIDTranslated(translations map[string]map[string]translation.Translation, lang, id string) bool {
-	_, contains := translations[lang][id]
-	return contains
-}
diff --git a/langs/i18n/translationProvider.go b/langs/i18n/translationProvider.go
index 4ce9b59fe..d191c0077 100644
--- a/langs/i18n/translationProvider.go
+++ b/langs/i18n/translationProvider.go
@@ -14,16 +14,19 @@
 package i18n
 
 import (
-	"errors"
+	"encoding/json"
 
 	"github.com/gohugoio/hugo/common/herrors"
+	"golang.org/x/text/language"
+	yaml "gopkg.in/yaml.v2"
 
-	"github.com/gohugoio/hugo/deps"
+	"github.com/BurntSushi/toml"
 	"github.com/gohugoio/hugo/helpers"
+	"github.com/nicksnyder/go-i18n/v2/i18n"
+
+	"github.com/gohugoio/hugo/deps"
 	"github.com/gohugoio/hugo/hugofs"
 	"github.com/gohugoio/hugo/source"
-	"github.com/nicksnyder/go-i18n/i18n/bundle"
-	"github.com/nicksnyder/go-i18n/i18n/language"
 	_errors "github.com/pkg/errors"
 )
 
@@ -42,13 +45,10 @@ func NewTranslationProvider() *TranslationProvider {
 func (tp *TranslationProvider) Update(d *deps.Deps) error {
 	spec := source.NewSourceSpec(d.PathSpec, nil)
 
-	i18nBundle := bundle.New()
-
-	en := language.GetPluralSpec("en")
-	if en == nil {
-		return errors.New("the English language has vanished like an old oak table")
-	}
-	var newLangs []string
+	bundle := i18n.NewBundle(language.English)
+	bundle.RegisterUnmarshalFunc("toml", toml.Unmarshal)
+	bundle.RegisterUnmarshalFunc("yaml", yaml.Unmarshal)
+	bundle.RegisterUnmarshalFunc("json", json.Unmarshal)
 
 	// The source dirs are ordered so the most important comes first. Since this is a
 	// last key win situation, we have to reverse the iteration order.
@@ -56,33 +56,18 @@ func (tp *TranslationProvider) Update(d *deps.Deps) error {
 	for i := len(dirs) - 1; i >= 0; i-- {
 		dir := dirs[i]
 		src := spec.NewFilesystemFromFileMetaInfo(dir)
-
 		files, err := src.Files()
 		if err != nil {
 			return err
 		}
-
-		for _, r := range files {
-			currentSpec := language.GetPluralSpec(r.BaseFileName())
-			if currentSpec == nil {
-				// This may is a language code not supported by go-i18n, it may be
-				// Klingon or ... not even a fake language. Make sure it works.
-				newLangs = append(newLangs, r.BaseFileName())
-			}
-		}
-
-		if len(newLangs) > 0 {
-			language.RegisterPluralSpec(newLangs, en)
-		}
-
 		for _, file := range files {
-			if err := addTranslationFile(i18nBundle, file); err != nil {
+			if err := addTranslationFile(bundle, file); err != nil {
 				return err
 			}
 		}
 	}
 
-	tp.t = NewTranslator(i18nBundle, d.Cfg, d.Log)
+	tp.t = NewTranslator(bundle, d.Cfg, d.Log)
 
 	d.Translate = tp.t.Func(d.Language.Lang)
 
@@ -90,16 +75,29 @@ func (tp *TranslationProvider) Update(d *deps.Deps) error {
 
 }
 
-func addTranslationFile(bundle *bundle.Bundle, r source.File) error {
+const artificialLangTagPrefix = "art-x-"
+
+func addTranslationFile(bundle *i18n.Bundle, r source.File) error {
 	f, err := r.FileInfo().Meta().Open()
 	if err != nil {
 		return _errors.Wrapf(err, "failed to open translations file %q:", r.LogicalName())
 	}
-	err = bundle.ParseTranslationFileBytes(r.LogicalName(), helpers.ReaderToBytes(f))
+
+	b := helpers.ReaderToBytes(f)
 	f.Close()
+
+	name := r.LogicalName()
+	lang := helpers.Filename(name)
+	tag := language.Make(lang)
+	if tag == language.Und {
+		name = artificialLangTagPrefix + name
+	}
+
+	_, err = bundle.ParseMessageFileBytes(b, name)
 	if err != nil {
 		return errWithFileContext(_errors.Wrapf(err, "failed to load translations"), r)
 	}
+
 	return nil
 }