1 files changed, 31 insertions, 0 deletions
diff --git a/tests/test_utils/tests.py b/tests/test_utils/tests.py
index 9255315e98..9465ace804 100644
--- a/tests/test_utils/tests.py
+++ b/tests/test_utils/tests.py
@@ -325,6 +325,37 @@ class AssertQuerysetEqualTests(TestCase):
             ordered=False
         )
 
+    def test_maxdiff(self):
+        names = ['Joe Smith %s' % i for i in range(20)]
+        Person.objects.bulk_create([Person(name=name) for name in names])
+        names.append('Extra Person')
+
+        with self.assertRaises(AssertionError) as ctx:
+            self.assertQuerysetEqual(
+                Person.objects.filter(name__startswith='Joe'),
+                names,
+                ordered=False,
+                transform=lambda p: p.name,
+            )
+        self.assertIn('Set self.maxDiff to None to see it.', str(ctx.exception))
+
+        original = self.maxDiff
+        self.maxDiff = None
+        try:
+            with self.assertRaises(AssertionError) as ctx:
+                self.assertQuerysetEqual(
+                    Person.objects.filter(name__startswith='Joe'),
+                    names,
+                    ordered=False,
+                    transform=lambda p: p.name,
+                )
+        finally:
+            self.maxDiff = original
+        exception_msg = str(ctx.exception)
+        self.assertNotIn('Set self.maxDiff to None to see it.', exception_msg)
+        for name in names:
+            self.assertIn(name, exception_msg)
+
 
 class AssertQuerysetEqualDeprecationTests(TestCase):
     @classmethod