mirror of
https://github.com/django/django.git
synced 2024-12-29 12:36:08 +00:00
96 lines
4.4 KiB
Python
96 lines
4.4 KiB
Python
from __future__ import unicode_literals
|
|
|
|
from django.test import TestCase
|
|
|
|
from .models import Reporter, Article
|
|
|
|
|
|
class ManyToOneNullTests(TestCase):
|
|
def setUp(self):
|
|
# Create a Reporter.
|
|
self.r = Reporter(name='John Smith')
|
|
self.r.save()
|
|
# Create an Article.
|
|
self.a = Article(headline="First", reporter=self.r)
|
|
self.a.save()
|
|
# Create an Article via the Reporter object.
|
|
self.a2 = self.r.article_set.create(headline="Second")
|
|
# Create an Article with no Reporter by passing "reporter=None".
|
|
self.a3 = Article(headline="Third", reporter=None)
|
|
self.a3.save()
|
|
# Create another article and reporter
|
|
self.r2 = Reporter(name='Paul Jones')
|
|
self.r2.save()
|
|
self.a4 = self.r2.article_set.create(headline='Fourth')
|
|
|
|
def test_get_related(self):
|
|
self.assertEqual(self.a.reporter.id, self.r.id)
|
|
# Article objects have access to their related Reporter objects.
|
|
r = self.a.reporter
|
|
self.assertEqual(r.id, self.r.id)
|
|
|
|
def test_created_via_related_set(self):
|
|
self.assertEqual(self.a2.reporter.id, self.r.id)
|
|
|
|
def test_related_set(self):
|
|
# Reporter objects have access to their related Article objects.
|
|
self.assertQuerysetEqual(self.r.article_set.all(),
|
|
['<Article: First>', '<Article: Second>'])
|
|
self.assertQuerysetEqual(self.r.article_set.filter(headline__startswith='Fir'),
|
|
['<Article: First>'])
|
|
self.assertEqual(self.r.article_set.count(), 2)
|
|
|
|
def test_created_without_related(self):
|
|
self.assertEqual(self.a3.reporter, None)
|
|
# Need to reget a3 to refresh the cache
|
|
a3 = Article.objects.get(pk=self.a3.pk)
|
|
self.assertRaises(AttributeError, getattr, a3.reporter, 'id')
|
|
# Accessing an article's 'reporter' attribute returns None
|
|
# if the reporter is set to None.
|
|
self.assertEqual(a3.reporter, None)
|
|
# To retrieve the articles with no reporters set, use "reporter__isnull=True".
|
|
self.assertQuerysetEqual(Article.objects.filter(reporter__isnull=True),
|
|
['<Article: Third>'])
|
|
# We can achieve the same thing by filtering for the case where the
|
|
# reporter is None.
|
|
self.assertQuerysetEqual(Article.objects.filter(reporter=None),
|
|
['<Article: Third>'])
|
|
# Set the reporter for the Third article
|
|
self.assertQuerysetEqual(self.r.article_set.all(),
|
|
['<Article: First>', '<Article: Second>'])
|
|
self.r.article_set.add(a3)
|
|
self.assertQuerysetEqual(self.r.article_set.all(),
|
|
['<Article: First>', '<Article: Second>', '<Article: Third>'])
|
|
# Remove an article from the set, and check that it was removed.
|
|
self.r.article_set.remove(a3)
|
|
self.assertQuerysetEqual(self.r.article_set.all(),
|
|
['<Article: First>', '<Article: Second>'])
|
|
self.assertQuerysetEqual(Article.objects.filter(reporter__isnull=True),
|
|
['<Article: Third>'])
|
|
|
|
def test_remove_from_wrong_set(self):
|
|
self.assertQuerysetEqual(self.r2.article_set.all(), ['<Article: Fourth>'])
|
|
# Try to remove a4 from a set it does not belong to
|
|
self.assertRaises(Reporter.DoesNotExist, self.r.article_set.remove, self.a4)
|
|
self.assertQuerysetEqual(self.r2.article_set.all(), ['<Article: Fourth>'])
|
|
|
|
def test_assign_clear_related_set(self):
|
|
# Use descriptor assignment to allocate ForeignKey. Null is legal, so
|
|
# existing members of set that are not in the assignment set are set null
|
|
self.r2.article_set = [self.a2, self.a3]
|
|
self.assertQuerysetEqual(self.r2.article_set.all(),
|
|
['<Article: Second>', '<Article: Third>'])
|
|
# Clear the rest of the set
|
|
self.r.article_set.clear()
|
|
self.assertQuerysetEqual(self.r.article_set.all(), [])
|
|
self.assertQuerysetEqual(Article.objects.filter(reporter__isnull=True),
|
|
['<Article: First>', '<Article: Fourth>'])
|
|
|
|
def test_clear_efficiency(self):
|
|
r = Reporter.objects.create()
|
|
for _ in range(3):
|
|
r.article_set.create()
|
|
with self.assertNumQueries(1):
|
|
r.article_set.clear()
|
|
self.assertEqual(r.article_set.count(), 0)
|