Fixed #18149 -- Changed language codes for Chinese

Language codes for Chinese are zh_Hans (Simplified) and zh_Hant (Traditional).
Added support for browsers that still send the deprecated language codes.

Thanks to Olli Wang for the report.

2 files changed, 46 insertions, 2 deletions

diff --git a/tests/deprecation/tests.py b/tests/deprecation/tests.py
index f949bea24e..7d9ed16636 100644
--- a/tests/deprecation/tests.py
+++ b/tests/deprecation/tests.py
@@ -1,8 +1,8 @@
 from __future__ import unicode_literals
 import warnings
 
-from django.test import SimpleTestCase, RequestFactory
-from django.utils import six
+from django.test import SimpleTestCase, RequestFactory, override_settings
+from django.utils import six, translation
 from django.utils.deprecation import RenameMethodsBase
 
 
@@ -186,3 +186,22 @@ class DeprecatingRequestMergeDictTest(SimpleTestCase):
                 '`request.POST` instead.',
                 '`MergeDict` is deprecated, use `dict.update()` instead.',
             ])
+
+
+@override_settings(USE_I18N=True)
+class DeprecatedChineseLanguageCodes(SimpleTestCase):
+    def test_deprecation_warning(self):
+        warnings.simplefilter('always')
+
+        with warnings.catch_warnings(record=True) as recorded:
+            with translation.override('zh-cn'):
+                pass
+            with translation.override('zh-tw'):
+                pass
+            msgs = [str(warning.message) for warning in recorded]
+            self.assertEqual(msgs, [
+                "The use of the language code 'zh-cn' is deprecated. "
+                "Please use the 'zh-hans' translation instead.",
+                "The use of the language code 'zh-tw' is deprecated. "
+                "Please use the 'zh-hant' translation instead.",
+            ])
diff --git a/tests/i18n/tests.py b/tests/i18n/tests.py
index 76f59bf919..f68a7361f6 100644
--- a/tests/i18n/tests.py
+++ b/tests/i18n/tests.py
@@ -871,6 +871,31 @@ class MiscTests(TransRealMixin, TestCase):
         r.META = {'HTTP_ACCEPT_LANGUAGE': 'zh-cn,de'}
         self.assertEqual(g(r), 'zh-cn')
 
+    @override_settings(
+        LANGUAGES=(
+            ('en', 'English'),
+            ('zh-hans', 'Simplified Chinese'),
+            ('zh-hant', 'Traditional Chinese'),
+        )
+    )
+    def test_support_for_deprecated_chinese_language_codes(self):
+        """
+        Some browsers (Firefox, IE etc) use deprecated language codes. As these
+        language codes will be removed in Django 1.9, these will be incorrectly
+        matched. For example zh-tw (traditional) will be interpreted as zh-hans
+        (simplified), which is wrong. So we should also accept these deprecated
+        language codes.
+
+        refs #18419 -- this is explicitly for browser compatibility
+        """
+        g = get_language_from_request
+        r = self.rf.get('/')
+        r.COOKIES = {}
+        r.META = {'HTTP_ACCEPT_LANGUAGE': 'zh-cn,en'}
+        self.assertEqual(g(r), 'zh-hans')
+        r.META = {'HTTP_ACCEPT_LANGUAGE': 'zh-tw,en'}
+        self.assertEqual(g(r), 'zh-hant')
+
     def test_parse_language_cookie(self):
         """
         Now test that we parse language preferences stored in a cookie correctly.