diff -r 5ff1fc726848 -r c6bca38c1cbf parts/django/tests/regressiontests/utils/checksums.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/parts/django/tests/regressiontests/utils/checksums.py	Sat Jan 08 11:20:57 2011 +0530
@@ -0,0 +1,29 @@
+import unittest
+
+from django.utils import checksums
+
+class TestUtilsChecksums(unittest.TestCase):
+
+    def check_output(self, function, value, output=None):
+        """
+        Check that function(value) equals output.  If output is None,
+        check that function(value) equals value.
+        """
+        if output is None:
+            output = value
+        self.assertEqual(function(value), output)
+
+    def test_luhn(self):
+        f = checksums.luhn
+        items = (
+            (4111111111111111, True), ('4111111111111111', True),
+            (4222222222222, True), (378734493671000, True),
+            (5424000000000015, True), (5555555555554444, True),
+            (1008, True), ('0000001008', True), ('000000001008', True),
+            (4012888888881881, True), (1234567890123456789012345678909, True),
+            (4111111111211111, False), (42222222222224, False),
+            (100, False), ('100', False), ('0000100', False),
+            ('abc', False), (None, False), (object(), False),
+        )
+        for value, output in items:
+            self.check_output(f, value, output)