[1.6.x] Fixed #21307 -- Moved TransRealMixin to django.test.utils.

51d2e1fb23 from master.

1 files changed, 18 insertions, 0 deletions

diff --git a/django/test/utils.py b/django/test/utils.py
index 535a70b4f7..818ccafdf3 100644
--- a/django/test/utils.py
+++ b/django/test/utils.py
@@ -2,6 +2,7 @@ from contextlib import contextmanager
 import logging
 import re
 import sys
+from threading import local
 import time
 import warnings
 from functools import wraps
@@ -441,6 +442,23 @@ def patch_logger(logger_name, log_level):
         setattr(logger, log_level, orig)
 
 
+class TransRealMixin(object):
+    """This is the only way to reset the translation machinery. Otherwise
+    the test suite occasionally fails because of global state pollution
+    between tests."""
+    def flush_caches(self):
+        from django.utils.translation import trans_real
+        trans_real._translations = {}
+        trans_real._active = local()
+        trans_real._default = None
+        trans_real._accepted = {}
+        trans_real._checked_languages = {}
+
+    def tearDown(self):
+        self.flush_caches()
+        super(TransRealMixin, self).tearDown()
+
+
 # On OSes that don't provide tzset (Windows), we can't set the timezone
 # in which the program runs. As a consequence, we must skip tests that
 # don't enforce a specific timezone (with timezone.override or equivalent),