python/lib/django_1_4/tests/modeltests/ordering/tests.py

   1 from __future__ import absolute_import
   2
   3 from datetime import datetime
   4 from operator import attrgetter
   5
   6 from django.test import TestCase
   7
   8 from .models import Article, ArticlePKOrdering
   9
  10
  11 class OrderingTests(TestCase):
  12     def test_basic(self):
  13         a1 = Article.objects.create(
  14             headline="Article 1", pub_date=datetime(2005, 7, 26)
  15         )
  16         a2 = Article.objects.create(
  17             headline="Article 2", pub_date=datetime(2005, 7, 27)
  18         )
  19         a3 = Article.objects.create(
  20             headline="Article 3", pub_date=datetime(2005, 7, 27)
  21         )
  22         a4 = Article.objects.create(
  23             headline="Article 4", pub_date=datetime(2005, 7, 28)
  24         )
  25
  26         # By default, Article.objects.all() orders by pub_date descending, then
  27         # headline ascending.
  28         self.assertQuerysetEqual(
  29             Article.objects.all(), [
  30                 "Article 4",
  31                 "Article 2",
  32                 "Article 3",
  33                 "Article 1",
  34             ],
  35             attrgetter("headline")
  36         )
  37
  38         # Override ordering with order_by, which is in the same format as the
  39         # ordering attribute in models.
  40         self.assertQuerysetEqual(
  41             Article.objects.order_by("headline"), [
  42                 "Article 1",
  43                 "Article 2",
  44                 "Article 3",
  45                 "Article 4",
  46             ],
  47             attrgetter("headline")
  48         )
  49         self.assertQuerysetEqual(
  50             Article.objects.order_by("pub_date", "-headline"), [
  51                 "Article 1",
  52                 "Article 3",
  53                 "Article 2",
  54                 "Article 4",
  55             ],
  56             attrgetter("headline")
  57         )
  58
  59         # Only the last order_by has any effect (since they each override any
  60         # previous ordering).
  61         self.assertQuerysetEqual(
  62             Article.objects.order_by("id"), [
  63                 "Article 1",
  64                 "Article 2",
  65                 "Article 3",
  66                 "Article 4",
  67             ],
  68             attrgetter("headline")
  69         )
  70         self.assertQuerysetEqual(
  71             Article.objects.order_by("id").order_by("-headline"), [
  72                 "Article 4",
  73                 "Article 3",
  74                 "Article 2",
  75                 "Article 1",
  76             ],
  77             attrgetter("headline")
  78         )
  79
  80         # Use the 'stop' part of slicing notation to limit the results.
  81         self.assertQuerysetEqual(
  82             Article.objects.order_by("headline")[:2], [
  83                 "Article 1",
  84                 "Article 2",
  85             ],
  86             attrgetter("headline")
  87         )
  88
  89         # Use the 'stop' and 'start' parts of slicing notation to offset the
  90         # result list.
  91         self.assertQuerysetEqual(
  92             Article.objects.order_by("headline")[1:3], [
  93                 "Article 2",
  94                 "Article 3",
  95             ],
  96             attrgetter("headline")
  97         )
  98
  99         # Getting a single item should work too:
 100         self.assertEqual(Article.objects.all()[0], a4)
 101
 102         # Use '?' to order randomly.
 103         self.assertEqual(
 104             len(list(Article.objects.order_by("?"))), 4
 105         )
 106
 107         # Ordering can be reversed using the reverse() method on a queryset.
 108         # This allows you to extract things like "the last two items" (reverse
 109         # and then take the first two).
 110         self.assertQuerysetEqual(
 111             Article.objects.all().reverse()[:2], [
 112                 "Article 1",
 113                 "Article 3",
 114             ],
 115             attrgetter("headline")
 116         )
 117
 118         # Ordering can be based on fields included from an 'extra' clause
 119         self.assertQuerysetEqual(
 120             Article.objects.extra(select={"foo": "pub_date"}, order_by=["foo", "headline"]), [
 121                 "Article 1",
 122                 "Article 2",
 123                 "Article 3",
 124                 "Article 4",
 125             ],
 126             attrgetter("headline")
 127         )
 128
 129         # If the extra clause uses an SQL keyword for a name, it will be
 130         # protected by quoting.
 131         self.assertQuerysetEqual(
 132             Article.objects.extra(select={"order": "pub_date"}, order_by=["order", "headline"]), [
 133                 "Article 1",
 134                 "Article 2",
 135                 "Article 3",
 136                 "Article 4",
 137             ],
 138             attrgetter("headline")
 139         )
 140
 141     def test_order_by_pk(self):
 142         """
 143         Ensure that 'pk' works as an ordering option in Meta.
 144         Refs #8291.
 145         """
 146         a1 = ArticlePKOrdering.objects.create(
 147             pk=1, headline="Article 1", pub_date=datetime(2005, 7, 26)
 148         )
 149         a2 = ArticlePKOrdering.objects.create(
 150             pk=2, headline="Article 2", pub_date=datetime(2005, 7, 27)
 151         )
 152         a3 = ArticlePKOrdering.objects.create(
 153             pk=3, headline="Article 3", pub_date=datetime(2005, 7, 27)
 154         )
 155         a4 = ArticlePKOrdering.objects.create(
 156             pk=4, headline="Article 4", pub_date=datetime(2005, 7, 28)
 157         )
 158
 159         self.assertQuerysetEqual(
 160             ArticlePKOrdering.objects.all(), [
 161                 "Article 4",
 162                 "Article 3",
 163                 "Article 2",
 164                 "Article 1",
 165             ],
 166             attrgetter("headline")
 167         )