Merge pull request #151 from zgoda/lazy_ngettext

Add lazy implementation of ngettext()

Author: TkTech

.gitignore

@@ -5,3 +5,5 @@
 dist/
 docs/_build
 .tox/
+.vscode
+*.code-workspace

flask_babel/__init__.py

@@ -620,6 +620,21 @@ def index():
     return LazyString(gettext, string, **variables)
 
 
+def lazy_ngettext(singular, plural, num, **variables):
+    """Like :func:`ngettext` but the string returned is lazy which means
+    it will be translated when it is used as an actual string.
+
+    Example::
+
+        apples = lazy_ngettext(u'%(num)d Apple', u'%(num)d Apples', num=len(apples))
+
+        @app.route('/')
+        def index():
+            return unicode(apples)
+    """
+    return LazyString(ngettext, singular, plural, num, **variables)
+
+
 def lazy_pgettext(context, string, **variables):
     """Like :func:`pgettext` but the string returned is lazy which means
     it will be translated when it is used as an actual string.

tests/tests.py

@@ -12,7 +12,7 @@
 import flask
 from datetime import datetime, timedelta
 import flask_babel as babel
-from flask_babel import gettext, ngettext, lazy_gettext, get_translations
+from flask_babel import gettext, ngettext, lazy_gettext, lazy_ngettext, get_translations
 from babel.support import NullTranslations
 from flask_babel._compat import text_type
 
@@ -266,6 +266,18 @@ def test_lazy_gettext(self):
             assert text_type(yes) == 'Yes'
             assert yes.__html__() == 'Yes'
 
+    def test_lazy_ngettext(self):
+        app = flask.Flask(__name__)
+        babel.Babel(app, default_locale='de_DE')
+        one_apple = lazy_ngettext(u'%(num)s Apple', u'%(num)s Apples', 1)
+        with app.test_request_context():
+            assert text_type(one_apple) == '1 Apfel'
+            assert one_apple.__html__() == '1 Apfel'
+        two_apples = lazy_ngettext(u'%(num)s Apple', u'%(num)s Apples', 2)
+        with app.test_request_context():
+            assert text_type(two_apples) == u'2 Äpfel'
+            assert two_apples.__html__() == u'2 Äpfel'
+
     def test_list_translations(self):
         app = flask.Flask(__name__)
         b = babel.Babel(app, default_locale='de_DE')