1 files changed, 9 insertions, 0 deletions
diff --git a/tests/cache/tests.py b/tests/cache/tests.py
index dca08ee081..e77cec9151 100644
--- a/tests/cache/tests.py
+++ b/tests/cache/tests.py
@@ -65,6 +65,11 @@ class Unpickable(object):
         raise pickle.PickleError()
 
 
+class UnpicklableType(object):
+    # Unpicklable using the default pickling protocol on Python 2.
+    __slots__ = 'a',
+
+
 @override_settings(CACHES={
     'default': {
         'BACKEND': 'django.core.cache.backends.dummy.DummyCache',
@@ -1221,6 +1226,10 @@ class FileBasedCacheTests(BaseCacheTests, TestCase):
         cache.set('foo', 'bar')
         os.path.exists(self.dirname)
 
+    def test_cache_write_unpickable_type(self):
+        # This fails if not using the highest pickling protocol on Python 2.
+        cache.set('unpickable', UnpicklableType())
+
 
 @override_settings(CACHES={
     'default': {