--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/parts/django/tests/modeltests/ordering/tests.py	Sat Jan 08 11:20:57 2011 +0530
@@ -0,0 +1,137 @@
+from datetime import datetime
+from operator import attrgetter
+
+from django.test import TestCase
+
+from models import Article
+
+
+class OrderingTests(TestCase):
+    def test_basic(self):
+        a1 = Article.objects.create(
+            headline="Article 1", pub_date=datetime(2005, 7, 26)
+        )
+        a2 = Article.objects.create(
+            headline="Article 2", pub_date=datetime(2005, 7, 27)
+        )
+        a3 = Article.objects.create(
+            headline="Article 3", pub_date=datetime(2005, 7, 27)
+        )
+        a4 = Article.objects.create(
+            headline="Article 4", pub_date=datetime(2005, 7, 28)
+        )
+
+        # By default, Article.objects.all() orders by pub_date descending, then
+        # headline ascending.
+        self.assertQuerysetEqual(
+            Article.objects.all(), [
+                "Article 4",
+                "Article 2",
+                "Article 3",
+                "Article 1",
+            ],
+            attrgetter("headline")
+        )
+
+        # Override ordering with order_by, which is in the same format as the
+        # ordering attribute in models.
+        self.assertQuerysetEqual(
+            Article.objects.order_by("headline"), [
+                "Article 1",
+                "Article 2",
+                "Article 3",
+                "Article 4",
+            ],
+            attrgetter("headline")
+        )
+        self.assertQuerysetEqual(
+            Article.objects.order_by("pub_date", "-headline"), [
+                "Article 1",
+                "Article 3",
+                "Article 2",
+                "Article 4",
+            ],
+            attrgetter("headline")
+        )
+
+        # Only the last order_by has any effect (since they each override any
+        # previous ordering).
+        self.assertQuerysetEqual(
+            Article.objects.order_by("id"), [
+                "Article 1",
+                "Article 2",
+                "Article 3",
+                "Article 4",
+            ],
+            attrgetter("headline")
+        )
+        self.assertQuerysetEqual(
+            Article.objects.order_by("id").order_by("-headline"), [
+                "Article 4",
+                "Article 3",
+                "Article 2",
+                "Article 1",
+            ],
+            attrgetter("headline")
+        )
+
+        # Use the 'stop' part of slicing notation to limit the results.
+        self.assertQuerysetEqual(
+            Article.objects.order_by("headline")[:2], [
+                "Article 1",
+                "Article 2",
+            ],
+            attrgetter("headline")
+        )
+
+        # Use the 'stop' and 'start' parts of slicing notation to offset the
+        # result list.
+        self.assertQuerysetEqual(
+            Article.objects.order_by("headline")[1:3], [
+                "Article 2",
+                "Article 3",
+            ],
+            attrgetter("headline")
+        )
+
+        # Getting a single item should work too:
+        self.assertEqual(Article.objects.all()[0], a4)
+
+        # Use '?' to order randomly.
+        self.assertEqual(
+            len(list(Article.objects.order_by("?"))), 4
+        )
+
+        # Ordering can be reversed using the reverse() method on a queryset.
+        # This allows you to extract things like "the last two items" (reverse
+        # and then take the first two).
+        self.assertQuerysetEqual(
+            Article.objects.all().reverse()[:2], [
+                "Article 1",
+                "Article 3",
+            ],
+            attrgetter("headline")
+        )
+
+        # Ordering can be based on fields included from an 'extra' clause
+        self.assertQuerysetEqual(
+            Article.objects.extra(select={"foo": "pub_date"}, order_by=["foo", "headline"]), [
+                "Article 1",
+                "Article 2",
+                "Article 3",
+                "Article 4",
+            ],
+            attrgetter("headline")
+        )
+
+        # If the extra clause uses an SQL keyword for a name, it will be
+        # protected by quoting.
+        self.assertQuerysetEqual(
+            Article.objects.extra(select={"order": "pub_date"}, order_by=["order", "headline"]), [
+                "Article 1",
+                "Article 2",
+                "Article 3",
+                "Article 4",
+            ],
+            attrgetter("headline")
+        )