add TranslateStringLocalizer() and improve core.go documentation

core/core.go

@@ -100,6 +100,7 @@ func Init(dataPath string, localizer *localizations.Localizer) error {
 	return nil
 }
 
+// WriteJSON writes a FullData to disk
 func (d *FullData) WriteJSON(dataPath string) error {
 	// use .new so if there's a corruption when writing the old file is intact
 	path := filepath.Join(dataPath, "comitium.json.new")
@@ -125,5 +126,14 @@ func (d *FullData) WriteJSON(dataPath string) error {
 // replace everything using the localizer replacements, and then substitute that
 // string into the template string.
 func TranslateString(template, localizerTag string, replacements *localizations.Replacements) string {
-	return fmt.Sprintf(template, Localizer.Get(localizerTag, replacements))
+	return TranslateStringLocalizer(Localizer, template, localizerTag, replacements)
+}
+
+// TranslateStringLocalizer takes a localizations.Localizer, template string, a
+// localizer tag, and a localizer replacement set and will get the localized
+// string from the localizer tag, replace everything using the localizer
+// replacements, and then substitute that string into the template string.
+// Should not be used once core.Init() is called, instead use TranslateString().
+func TranslateStringLocalizer(localizer *localizations.Localizer, template, localizerTag string, replacements *localizations.Replacements) string {
+	return fmt.Sprintf(template, localizer.Get(localizerTag, replacements))
 }