Feature plural translations

README.md

@@ -11,7 +11,7 @@ koa locales, i18n solution for koa:
 
 1. All locales resources location on `options.dirs`.
 2. resources file supports: `*.js`, `*.json`, `*.yml`, `*.yaml` and `*.properties`, see [examples](test/locales/).
-3. One api: `__(key[, value, ...])`.
+3. Api: `__(key[, value, ...])`, `__n(key, count[, value, ...])`.
 4. Auto detect request locale from `query`, `cookie` and `header: Accept-Language`.
 
 ## Installation
@@ -42,6 +42,7 @@ Patch locales functions to koa app.
 - {Application} app: koa app instance.
 - {Object} options: optional params.
   - {String} functionName: locale function name patch on koa context. Optional, default is `__`.
+  - {String} functionnName: locale function (with plurals management) name patch on koa context. Optional, default is `__n`.
   - {String} dirs: locales resources store directories. Optional, default is `['$PWD/locales']`.
   - {String} defaultLocale: default locale. Optional, default is `en-US`.
   - {String} queryField: locale field name on query. Optional, default is `locale`.
@@ -99,6 +100,86 @@ __('{a} {a} {b} {b} {b}', {a: 'foo', b: 'bar'})
 'foo foo bar bar bar'
 ```
 
+### `context.__n(key, count[, value1[, value2, ...]])`
+
+Get current request locale text with plural.
+
+Works with package [make-plural](https://github.com/eemeli/make-plural/tree/master/packages/plurals) package. Support approximately 200 languages.
+
+```js
+async function home(ctx) {
+  ctx.body = {
+    message: ctx.__n({one: 'I have one apple.', other: 'I have {0} apples.', 2, 2),
+  };
+}
+```
+
+**Note:**  
+The `count` parameter is not part of the displayed values. To have the number 
+`count` displayed, one must add this parameter to the list of values.
+
+
+Examples:
+
+```js
+// With english locale
+__n({one: 'I have one cat.', other: 'I have not one cat.'}, 0)
+=>
+'I have not one cat.'
+
+// With french locale
+// Note that the parameter 0 is put two times:
+// The first one is used as the count parameter and the second is displayed as
+// first value ({0}).
+__n({one: "J'ai {0} chat.", other: "J'ai {0} chats."}, 0, 0)
+=>
+"J'ai 0 chat."
+
+// If the targeted plural is not found (here 'one'), 'other' is selected.
+__n({other: '{a} {a} {b} {b} {b}'}, 1, {a: 'foo', b: 'bar'})
+=>
+'foo foo bar bar bar'
+```
+
+Russian json file (from [i18n](https://github.com/mashpie/i18n-node#i18n__n)
+example):
+```json
+{
+  "cat_key": {
+    "one": "%d кошка",
+    "few": "%d кошки",
+    "many": "%d кошек",
+    "other": "%d кошка",
+  }
+}
+```
+Use:
+```js
+__n('cat_key', 0, 0);
+=>
+'0 кошек'
+
+__n('cat_key', 1, 1); 
+=>
+'1 кошка'
+
+__n('cat_key', 2, 2);
+=>
+'2 кошки'
+
+__n('cat_key', 5, 5); 
+=>
+'5 кошек'
+
+__n('cat_key', 6, 6);
+=>
+'6 кошек'
+
+__n('cat_key', 21, 21);
+=>
+'21 кошка'
+```
+
 ### `context.__getLocale()`
 
 Get locale from query / cookie and header.
@@ -149,6 +230,44 @@ app.use(async (ctx, next) => {
 });
 ```
 
+### `app.__n(locale, key, count[, value1[, value2, ...]])`
+
+Get the given locale text with plural management on application level.
+
+```js
+console.log(app.__n('zh', {other: 'Hello'}, 0));
+// stdout '你好' for Chinese
+```
+
+## Usage on template
+
+```js
+this.state.__n = this.__n.bind(this);
+```
+
+[Nunjucks] example:
+
+```html
+{{ __n({other: 'Hello, %s'}, 2, user.name) }}
+```
+
+[Pug] example:
+
+```pug
+p= __n({other: 'Hello, %s'}, 2, user.name)
+```
+
+[Koa-pug] integration:
+
+You can set the property *locals* on the KoaPug instance, where the default locals are stored.
+
+```js
+app.use(async (ctx, next) => {
+  koaPug.locals.__n = ctx.__n.bind(ctx);
+  await next();
+});
+```
+
 ## Debugging
 
 If you are interested on knowing what locale was chosen and why you can enable the debug messages from [debug].

index.js

@@ -10,6 +10,7 @@ const path = require('path');
 const ms = require('humanize-ms');
 const assign = require('object-assign');
 const yaml = require('js-yaml');
+const MakePlural = require('make-plural');
 
 const DEFAULT_OPTIONS = {
   defaultLocale: 'en-US',
@@ -21,6 +22,7 @@ const DEFAULT_OPTIONS = {
   dir: undefined,
   dirs: [path.join(process.cwd(), 'locales')],
   functionName: '__',
+  functionnName: '__n',
 };
 
 module.exports = function (app, options) {
@@ -35,7 +37,9 @@ module.exports = function (app, options) {
   const localeDir = options.dir;
   const localeDirs = options.dirs;
   const functionName = options.functionName;
+  const functionnName = options.functionnName;
   const resources = {};
+  const PluralsForLocale = {};
 
   /**
    * @Deprecated Use options.dirs instead.
@@ -81,7 +85,7 @@ module.exports = function (app, options) {
   function gettext(locale, key, value) {
     if (arguments.length === 0 || arguments.length === 1) {
       // __()
-      // --('en')
+      // __('en')
       return '';
     }
 
@@ -133,6 +137,93 @@ module.exports = function (app, options) {
 
   app[functionName] = gettext;
 
+  function gettextn(locale, key, count, value) {
+    if (arguments.length === 0 || arguments.length === 1) {
+      // __n()
+      // __n('en')
+      return '';
+    }
+
+    if (arguments.length === 2) {
+      // __n('en', key)
+      return gettext(locale, key);
+    }
+
+    const resource = resources[locale] || {};
+
+    // enforce number
+    count = Number(count);
+
+    //**************************************************************//
+    // Directly adapted from __n function of i18n module :
+    // https://github.com/mashpie/i18n-node/blob/master/i18n.js
+    let p;
+    // create a new Plural for locale
+    // and try to cache instance
+    if (PluralsForLocale[locale]) {
+      p = PluralsForLocale[locale];
+    } else {
+    // split locales with a region code
+      const lc = locale.toLowerCase().split(/[_-\s]+/)
+        .filter(function(el){ return true && el; });
+      // take the first part of locale, fallback to full locale
+      p = MakePlural[lc[0] || locale];
+      PluralsForLocale[locale] = p;
+    }
+    // fallback to 'other' on case of missing translations
+    let text = resource[key + '.' + p(count)] || resource[key + '.other'];
+    //**************************************************************//
+
+    if (text === undefined && isObject(key)) {
+      text = key[p(count)] || key['other'];
+    }
+
+    if (text === undefined) {
+      text = key;
+    }
+
+    debugSilly('%s: %j => %j', locale, key, text);
+    if (!text) {
+      return '';
+    }
+
+    if (arguments.length === 3) {
+      // __(locale, key, count)
+      return text;
+    }
+    if (arguments.length === 4) {
+      if (isObject(value)) {
+        // __(locale, key, count, object)
+        // __('zh', {"one": '{a} {b} {b} {a}', "other": '{b} {a} {a} {b}'}, 1, {a: 'foo', b: 'bar'})
+        // =>
+        // foo bar bar foo
+        return formatWithObject(text, value);
+      }
+
+      if (Array.isArray(value)) {
+        // __(locale, key, array)
+        // __('zh', {"one": '{0} {1} {1} {0}', "other": '{1} {0} {0} {1}'}, 2, ['foo', 'bar'])
+        // =>
+        // bar foo foo bar
+        return formatWithArray(text, value);
+      }
+
+      // __(locale, key, count, value)
+      return util.format(text, value);
+    }
+
+    // __(locale, key, count, value1, ...)
+    const args = new Array(arguments.length - 2);
+    args[0] = text;
+    for(let i = 3; i < arguments.length; i++) {
+      args[i - 2] = arguments[i];
+    }
+    return util.format.apply(util, args);
+
+  }
+
+  app[functionnName] = gettextn;
+
   app.context[functionName] = function (key, value) {
     if (arguments.length === 0) {
       // __()
@@ -154,6 +245,32 @@ module.exports = function (app, options) {
     return gettext.apply(this, args);
   };
 
+  app.context[functionnName] = function (key, count, value) {
+    if (arguments.length === 0) {
+      // __n()
+      return '';
+    }
+
+    const locale = this.__getLocale();
+    if (arguments.length === 1) {
+      // __n(key)
+      return gettext(locale, key);
+    }
+
+    if (arguments.length === 2) {
+      return gettextn(locale, key, count);
+    }
+    if (arguments.length === 3) {
+      return gettextn(locale, key, count, value);
+    }
+    const args = new Array(arguments.length + 1);
+    args[0] = locale;
+    for(let i = 0; i < arguments.length; i++) {
+      args[i + 1] = arguments[i];
+    }
+    return gettextn.apply(this, args);
+  };
+
   // 1. query: /?locale=en-US
   // 2. cookie: locale=zh-TW
   // 3. header: Accept-Language: zh-CN,zh;q=0.5

package.json

@@ -19,6 +19,7 @@
     "humanize-ms": "^1.2.0",
     "ini": "^1.3.4",
     "js-yaml": "^3.13.1",
+    "make-plural": "^6.2.1",
     "npminstall": "^3.23.0",
     "object-assign": "^4.1.0"
   },