[1.2.X] Fixed #15129 -- Fixed stability of data input/output L10N format modules priority order. Thanks tonnzor for the report and fix.

Backport of [15402] from trunk

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15403 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 17 insertions, 3 deletions

diff --git a/django/utils/formats.py b/django/utils/formats.py
index d0c63fb96f..a73b596dbe 100644
--- a/django/utils/formats.py
+++ b/django/utils/formats.py
@@ -36,12 +36,12 @@ def iter_format_modules(lang):
 
 def get_format_modules(reverse=False):
     """
-    Returns an iterator over the format modules found
+    Returns a list of the format modules found
     """
     lang = get_language()
     modules = _format_modules_cache.setdefault(lang, list(iter_format_modules(lang)))
     if reverse:
-        modules.reverse()
+        return list(reversed(modules))
     return modules
 
 def get_format(format_type):
diff --git a/tests/regressiontests/i18n/tests.py b/tests/regressiontests/i18n/tests.py
index e9c4566227..e7f78814b0 100644
--- a/tests/regressiontests/i18n/tests.py
+++ b/tests/regressiontests/i18n/tests.py
@@ -8,7 +8,8 @@ import pickle
 from django.conf import settings
 from django.template import Template, Context
 from django.test import TestCase
-from django.utils.formats import get_format, date_format, time_format, localize, localize_input, iter_format_modules
+from django.utils.formats import (get_format, date_format, time_format,
+    localize, localize_input, iter_format_modules, get_format_modules)
 from django.utils.numberformat import format as nformat
 from django.utils.safestring import mark_safe, SafeString, SafeUnicode
 from django.utils.translation import (ugettext, ugettext_lazy, activate,
@@ -466,6 +467,19 @@ class FormattingTests(TestCase):
         finally:
             settings.USE_L10N = old_l10n
 
+    def test_get_format_modules_stability(self):
+        activate('de')
+        old_format_module_path = settings.FORMAT_MODULE_PATH
+        settings.FORMAT_MODULE_PATH = 'regressiontests.i18n.other.locale'
+        try:
+            settings.USE_L10N = True
+            old = "%r" % get_format_modules(reverse=True)
+            new = "%r" % get_format_modules(reverse=True) # second try
+            self.assertEqual(new, old, 'Value returned by get_formats_modules() must be preserved between calls.')
+        finally:
+            settings.FORMAT_MODULE_PATH = old_format_module_path
+            deactivate()
+
 
 class MiscTests(TestCase):