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from __future__ import absolute_import
from django.test import TestCase
from django.utils import six
from .models import Article, Publication
class ManyToManyTests(TestCase):
def setUp(self):
# Create a couple of Publications.
self.p1 = Publication.objects.create(id=None, title='The Python Journal')
self.p2 = Publication.objects.create(id=None, title='Science News')
self.p3 = Publication.objects.create(id=None, title='Science Weekly')
self.p4 = Publication.objects.create(title='Highlights for Children')
self.a1 = Article.objects.create(id=None, headline='Django lets you build Web apps easily')
self.a1.publications.add(self.p1)
self.a2 = Article.objects.create(id=None, headline='NASA uses Python')
self.a2.publications.add(self.p1, self.p2, self.p3, self.p4)
self.a3 = Article.objects.create(headline='NASA finds intelligent life on Earth')
self.a3.publications.add(self.p2)
self.a4 = Article.objects.create(headline='Oxygen-free diet works wonders')
self.a4.publications.add(self.p2)
def test_add(self):
# Create an Article.
a5 = Article(id=None, headline='Django lets you reate Web apps easily')
# You can't associate it with a Publication until it's been saved.
self.assertRaises(ValueError, getattr, a5, 'publications')
# Save it!
a5.save()
# Associate the Article with a Publication.
a5.publications.add(self.p1)
self.assertQuerysetEqual(a5.publications.all(),
['<Publication: The Python Journal>'])
# Create another Article, and set it to appear in both Publications.
a6 = Article(id=None, headline='ESA uses Python')
a6.save()
a6.publications.add(self.p1, self.p2)
a6.publications.add(self.p3)
# Adding a second time is OK
a6.publications.add(self.p3)
self.assertQuerysetEqual(a6.publications.all(),
[
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
# Adding an object of the wrong type raises TypeError
with six.assertRaisesRegex(self, TypeError, "'Publication' instance expected, got <Article.*"):
a6.publications.add(a5)
# Add a Publication directly via publications.add by using keyword arguments.
p4 = a6.publications.create(title='Highlights for Adults')
self.assertQuerysetEqual(a6.publications.all(),
[
'<Publication: Highlights for Adults>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
def test_reverse_add(self):
# Adding via the 'other' end of an m2m
a5 = Article(headline='NASA finds intelligent life on Mars')
a5.save()
self.p2.article_set.add(a5)
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA finds intelligent life on Mars>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(a5.publications.all(),
['<Publication: Science News>'])
# Adding via the other end using keywords
new_article = self.p2.article_set.create(headline='Carbon-free diet works wonders')
self.assertQuerysetEqual(
self.p2.article_set.all(),
[
'<Article: Carbon-free diet works wonders>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA finds intelligent life on Mars>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
a6 = self.p2.article_set.all()[3]
self.assertQuerysetEqual(a6.publications.all(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
def test_related_sets(self):
# Article objects have access to their related Publication objects.
self.assertQuerysetEqual(self.a1.publications.all(),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(self.a2.publications.all(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
# Publication objects have access to their related Article objects.
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.p1.article_set.all(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(Publication.objects.get(id=self.p4.id).article_set.all(),
['<Article: NASA uses Python>'])
def test_selects(self):
# We can perform kwarg queries across m2m relationships
self.assertQuerysetEqual(
Article.objects.filter(publications__id__exact=self.p1.id),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications__pk=self.p1.id),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications=self.p1.id),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications=self.p1),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications__title__startswith="Science"),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications__title__startswith="Science").distinct(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
# The count() function respects distinct() as well.
self.assertEqual(Article.objects.filter(publications__title__startswith="Science").count(), 4)
self.assertEqual(Article.objects.filter(publications__title__startswith="Science").distinct().count(), 3)
self.assertQuerysetEqual(
Article.objects.filter(publications__in=[self.p1.id,self.p2.id]).distinct(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications__in=[self.p1.id,self.p2]).distinct(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(
Article.objects.filter(publications__in=[self.p1,self.p2]).distinct(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
# Excluding a related item works as you would expect, too (although the SQL
# involved is a little complex).
self.assertQuerysetEqual(Article.objects.exclude(publications=self.p2),
['<Article: Django lets you build Web apps easily>'])
def test_reverse_selects(self):
# Reverse m2m queries are supported (i.e., starting at the table that
# doesn't have a ManyToManyField).
self.assertQuerysetEqual(Publication.objects.filter(id__exact=self.p1.id),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(Publication.objects.filter(pk=self.p1.id),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(
Publication.objects.filter(article__headline__startswith="NASA"),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
self.assertQuerysetEqual(Publication.objects.filter(article__id__exact=self.a1.id),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(Publication.objects.filter(article__pk=self.a1.id),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(Publication.objects.filter(article=self.a1.id),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(Publication.objects.filter(article=self.a1),
['<Publication: The Python Journal>'])
self.assertQuerysetEqual(
Publication.objects.filter(article__in=[self.a1.id,self.a2.id]).distinct(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
self.assertQuerysetEqual(
Publication.objects.filter(article__in=[self.a1.id,self.a2]).distinct(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
self.assertQuerysetEqual(
Publication.objects.filter(article__in=[self.a1,self.a2]).distinct(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
'<Publication: The Python Journal>',
])
def test_delete(self):
# If we delete a Publication, its Articles won't be able to access it.
self.p1.delete()
self.assertQuerysetEqual(Publication.objects.all(),
[
'<Publication: Highlights for Children>',
'<Publication: Science News>',
'<Publication: Science Weekly>',
])
self.assertQuerysetEqual(self.a1.publications.all(), [])
# If we delete an Article, its Publications won't be able to access it.
self.a2.delete()
self.assertQuerysetEqual(Article.objects.all(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: Oxygen-free diet works wonders>',
])
def test_bulk_delete(self):
# Bulk delete some Publications - references to deleted publications should go
Publication.objects.filter(title__startswith='Science').delete()
self.assertQuerysetEqual(Publication.objects.all(),
[
'<Publication: Highlights for Children>',
'<Publication: The Python Journal>',
])
self.assertQuerysetEqual(Article.objects.all(),
[
'<Article: Django lets you build Web apps easily>',
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.a2.publications.all(),
[
'<Publication: Highlights for Children>',
'<Publication: The Python Journal>',
])
# Bulk delete some articles - references to deleted objects should go
q = Article.objects.filter(headline__startswith='Django')
self.assertQuerysetEqual(q, ['<Article: Django lets you build Web apps easily>'])
q.delete()
# After the delete, the QuerySet cache needs to be cleared,
# and the referenced objects should be gone
self.assertQuerysetEqual(q, [])
self.assertQuerysetEqual(self.p1.article_set.all(),
['<Article: NASA uses Python>'])
def test_remove(self):
# Removing publication from an article:
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
'<Article: Oxygen-free diet works wonders>',
])
self.a4.publications.remove(self.p2)
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(self.a4.publications.all(), [])
# And from the other end
self.p2.article_set.remove(self.a3)
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA uses Python>',
])
self.assertQuerysetEqual(self.a3.publications.all(), [])
def test_assign(self):
# Relation sets can be assigned. Assignment clears any existing set members
self.p2.article_set = [self.a4, self.a3]
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.a4.publications.all(),
['<Publication: Science News>'])
self.a4.publications = [self.p3.id]
self.assertQuerysetEqual(self.p2.article_set.all(),
['<Article: NASA finds intelligent life on Earth>'])
self.assertQuerysetEqual(self.a4.publications.all(),
['<Publication: Science Weekly>'])
# An alternate to calling clear() is to assign the empty set
self.p2.article_set = []
self.assertQuerysetEqual(self.p2.article_set.all(), [])
self.a4.publications = []
self.assertQuerysetEqual(self.a4.publications.all(), [])
def test_assign_ids(self):
# Relation sets can also be set using primary key values
self.p2.article_set = [self.a4.id, self.a3.id]
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.a4.publications.all(),
['<Publication: Science News>'])
self.a4.publications = [self.p3.id]
self.assertQuerysetEqual(self.p2.article_set.all(),
['<Article: NASA finds intelligent life on Earth>'])
self.assertQuerysetEqual(self.a4.publications.all(),
['<Publication: Science Weekly>'])
def test_clear(self):
# Relation sets can be cleared:
self.p2.article_set.clear()
self.assertQuerysetEqual(self.p2.article_set.all(), [])
self.assertQuerysetEqual(self.a4.publications.all(), [])
# And you can clear from the other end
self.p2.article_set.add(self.a3, self.a4)
self.assertQuerysetEqual(self.p2.article_set.all(),
[
'<Article: NASA finds intelligent life on Earth>',
'<Article: Oxygen-free diet works wonders>',
])
self.assertQuerysetEqual(self.a4.publications.all(),
[
'<Publication: Science News>',
])
self.a4.publications.clear()
self.assertQuerysetEqual(self.a4.publications.all(), [])
self.assertQuerysetEqual(self.p2.article_set.all(),
['<Article: NASA finds intelligent life on Earth>'])
|
