/tests/modeltests/order_with_respect_to/tests.py

 1from operator import attrgetter
 2
 3from django.test import TestCase
 4
 5from models import Post, Question, Answer
 6
 7
 8class OrderWithRespectToTests(TestCase):
 9    def test_basic(self):
10        q1 = Question.objects.create(text="Which Beatle starts with the letter 'R'?")
11        q2 = Question.objects.create(text="What is your name?")
12        
13        Answer.objects.create(text="John", question=q1)
14        Answer.objects.create(text="Jonno", question=q2)
15        Answer.objects.create(text="Paul", question=q1)
16        Answer.objects.create(text="Paulo", question=q2)
17        Answer.objects.create(text="George", question=q1)
18        Answer.objects.create(text="Ringo", question=q1)
19        
20        # The answers will always be ordered in the order they were inserted.
21        self.assertQuerysetEqual(
22            q1.answer_set.all(), [
23                "John", "Paul", "George", "Ringo",
24            ],
25            attrgetter("text"),
26        )
27        
28        # We can retrieve the answers related to a particular object, in the
29        # order they were created, once we have a particular object.
30        a1 = Answer.objects.filter(question=q1)[0]
31        self.assertEqual(a1.text, "John")
32        a2 = a1.get_next_in_order()
33        self.assertEqual(a2.text, "Paul")
34        a4 = list(Answer.objects.filter(question=q1))[-1]
35        self.assertEqual(a4.text, "Ringo")
36        self.assertEqual(a4.get_previous_in_order().text, "George")
37        
38        # Determining (and setting) the ordering for a particular item is also
39        # possible.
40        id_list = [o.pk for o in q1.answer_set.all()]
41        self.assertEqual(a2.question.get_answer_order(), id_list)
42        
43        a5 = Answer.objects.create(text="Number five", question=q1)
44        
45        # It doesn't matter which answer we use to check the order, it will
46        # always be the same.
47        self.assertEqual(
48            a2.question.get_answer_order(), a5.question.get_answer_order()
49        )
50        
51        # The ordering can be altered:
52        id_list = [o.pk for o in q1.answer_set.all()]
53        x = id_list.pop()
54        id_list.insert(-1, x)
55        self.assertNotEqual(a5.question.get_answer_order(), id_list)
56        a5.question.set_answer_order(id_list)
57        self.assertQuerysetEqual(
58            q1.answer_set.all(), [
59                "John", "Paul", "George", "Number five", "Ringo"
60            ],
61            attrgetter("text")
62        )
63
64    def test_recursive_ordering(self):
65        p1 = Post.objects.create(title='1')
66        p2 = Post.objects.create(title='2')
67        p1_1 = Post.objects.create(title="1.1", parent=p1)
68        p1_2 = Post.objects.create(title="1.2", parent=p1)
69        p2_1 = Post.objects.create(title="2.1", parent=p2)
70        p1_3 = Post.objects.create(title="1.3", parent=p1)
71        self.assertEqual(p1.get_post_order(), [p1_1.pk, p1_2.pk, p1_3.pk])