/
tests.py
668 lines (597 loc) · 26.4 KB
/
tests.py
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from unittest import mock
from django.db import connection, transaction
from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
from django.utils.deprecation import RemovedInDjango60Warning
from .models import (
Article,
InheritedArticleA,
InheritedArticleB,
NullablePublicationThrough,
NullableTargetArticle,
Publication,
User,
)
class ManyToManyTests(TestCase):
@classmethod
def setUpTestData(cls):
# Create a couple of Publications.
cls.p1 = Publication.objects.create(title="The Python Journal")
cls.p2 = Publication.objects.create(title="Science News")
cls.p3 = Publication.objects.create(title="Science Weekly")
cls.p4 = Publication.objects.create(title="Highlights for Children")
cls.a1 = Article.objects.create(
headline="Django lets you build web apps easily"
)
cls.a1.publications.add(cls.p1)
cls.a2 = Article.objects.create(headline="NASA uses Python")
cls.a2.publications.add(cls.p1, cls.p2, cls.p3, cls.p4)
cls.a3 = Article.objects.create(headline="NASA finds intelligent life on Earth")
cls.a3.publications.add(cls.p2)
cls.a4 = Article.objects.create(headline="Oxygen-free diet works wonders")
cls.a4.publications.add(cls.p2)
def test_add(self):
# Create an Article.
a5 = Article(headline="Django lets you create web apps easily")
# You can't associate it with a Publication until it's been saved.
msg = (
'"<Article: Django lets you create web apps easily>" needs to have '
'a value for field "id" before this many-to-many relationship can be used.'
)
with self.assertRaisesMessage(ValueError, msg):
getattr(a5, "publications")
# Save it!
a5.save()
# Associate the Article with a Publication.
a5.publications.add(self.p1)
self.assertSequenceEqual(a5.publications.all(), [self.p1])
# Create another Article, and set it to appear in both Publications.
a6 = Article(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.assertSequenceEqual(
a6.publications.all(),
[self.p2, self.p3, self.p1],
)
# Adding an object of the wrong type raises TypeError
msg = (
"'Publication' instance expected, got <Article: Django lets you create web "
"apps easily>"
)
with self.assertRaisesMessage(TypeError, msg):
with transaction.atomic():
a6.publications.add(a5)
# Add a Publication directly via publications.add by using keyword arguments.
p5 = a6.publications.create(title="Highlights for Adults")
self.assertSequenceEqual(
a6.publications.all(),
[p5, self.p2, self.p3, self.p1],
)
def test_add_remove_set_by_pk(self):
a5 = Article.objects.create(headline="Django lets you create web apps easily")
a5.publications.add(self.p1.pk)
self.assertSequenceEqual(a5.publications.all(), [self.p1])
a5.publications.set([self.p2.pk])
self.assertSequenceEqual(a5.publications.all(), [self.p2])
a5.publications.remove(self.p2.pk)
self.assertSequenceEqual(a5.publications.all(), [])
def test_add_remove_set_by_to_field(self):
user_1 = User.objects.create(username="Jean")
user_2 = User.objects.create(username="Joe")
a5 = Article.objects.create(headline="Django lets you create web apps easily")
a5.authors.add(user_1.username)
self.assertSequenceEqual(a5.authors.all(), [user_1])
a5.authors.set([user_2.username])
self.assertSequenceEqual(a5.authors.all(), [user_2])
a5.authors.remove(user_2.username)
self.assertSequenceEqual(a5.authors.all(), [])
def test_related_manager_refresh(self):
user_1 = User.objects.create(username="Jean")
user_2 = User.objects.create(username="Joe")
self.a3.authors.add(user_1.username)
self.assertSequenceEqual(user_1.article_set.all(), [self.a3])
# Change the username on a different instance of the same user.
user_1_from_db = User.objects.get(pk=user_1.pk)
self.assertSequenceEqual(user_1_from_db.article_set.all(), [self.a3])
user_1_from_db.username = "Paul"
self.a3.authors.set([user_2.username])
user_1_from_db.save()
# Assign a different article.
self.a4.authors.add(user_1_from_db.username)
self.assertSequenceEqual(user_1_from_db.article_set.all(), [self.a4])
# Refresh the instance with an evaluated related manager.
user_1.refresh_from_db()
self.assertEqual(user_1.username, "Paul")
self.assertSequenceEqual(user_1.article_set.all(), [self.a4])
def test_add_remove_invalid_type(self):
msg = "Field 'id' expected a number but got 'invalid'."
for method in ["add", "remove"]:
with self.subTest(method), self.assertRaisesMessage(ValueError, msg):
getattr(self.a1.publications, method)("invalid")
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.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, a5, self.a2, self.a4],
)
self.assertSequenceEqual(a5.publications.all(), [self.p2])
# Adding via the other end using keywords
a6 = self.p2.article_set.create(headline="Carbon-free diet works wonders")
self.assertSequenceEqual(
self.p2.article_set.all(),
[a6, self.a3, a5, self.a2, self.a4],
)
a6 = self.p2.article_set.all()[3]
self.assertSequenceEqual(
a6.publications.all(),
[self.p4, self.p2, self.p3, self.p1],
)
@skipUnlessDBFeature("supports_ignore_conflicts")
def test_fast_add_ignore_conflicts(self):
"""
A single query is necessary to add auto-created through instances if
the database backend supports bulk_create(ignore_conflicts) and no
m2m_changed signals receivers are connected.
"""
with self.assertNumQueries(1):
self.a1.publications.add(self.p1, self.p2)
@skipIfDBFeature("supports_ignore_conflicts")
def test_add_existing_different_type(self):
# A single SELECT query is necessary to compare existing values to the
# provided one; no INSERT should be attempted.
with self.assertNumQueries(1):
self.a1.publications.add(str(self.p1.pk))
self.assertEqual(self.a1.publications.get(), self.p1)
@skipUnlessDBFeature("supports_ignore_conflicts")
def test_slow_add_ignore_conflicts(self):
manager_cls = self.a1.publications.__class__
# Simulate a race condition between the missing ids retrieval and
# the bulk insertion attempt.
missing_target_ids = {self.p1.id}
# Disable fast-add to test the case where the slow add path is taken.
add_plan = (True, False, False)
with mock.patch.object(
manager_cls, "_get_missing_target_ids", return_value=missing_target_ids
) as mocked:
with mock.patch.object(manager_cls, "_get_add_plan", return_value=add_plan):
self.a1.publications.add(self.p1)
mocked.assert_called_once()
def test_related_sets(self):
# Article objects have access to their related Publication objects.
self.assertSequenceEqual(self.a1.publications.all(), [self.p1])
self.assertSequenceEqual(
self.a2.publications.all(),
[self.p4, self.p2, self.p3, self.p1],
)
# Publication objects have access to their related Article objects.
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a2, self.a4],
)
self.assertSequenceEqual(
self.p1.article_set.all(),
[self.a1, self.a2],
)
self.assertSequenceEqual(
Publication.objects.get(id=self.p4.id).article_set.all(),
[self.a2],
)
def test_selects(self):
# We can perform kwarg queries across m2m relationships
self.assertSequenceEqual(
Article.objects.filter(publications__id__exact=self.p1.id),
[self.a1, self.a2],
)
self.assertSequenceEqual(
Article.objects.filter(publications__pk=self.p1.id),
[self.a1, self.a2],
)
self.assertSequenceEqual(
Article.objects.filter(publications=self.p1.id),
[self.a1, self.a2],
)
self.assertSequenceEqual(
Article.objects.filter(publications=self.p1),
[self.a1, self.a2],
)
self.assertSequenceEqual(
Article.objects.filter(publications__title__startswith="Science"),
[self.a3, self.a2, self.a2, self.a4],
)
self.assertSequenceEqual(
Article.objects.filter(
publications__title__startswith="Science"
).distinct(),
[self.a3, self.a2, self.a4],
)
# 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.assertSequenceEqual(
Article.objects.filter(
publications__in=[self.p1.id, self.p2.id]
).distinct(),
[self.a1, self.a3, self.a2, self.a4],
)
self.assertSequenceEqual(
Article.objects.filter(publications__in=[self.p1.id, self.p2]).distinct(),
[self.a1, self.a3, self.a2, self.a4],
)
self.assertSequenceEqual(
Article.objects.filter(publications__in=[self.p1, self.p2]).distinct(),
[self.a1, self.a3, self.a2, self.a4],
)
# Excluding a related item works as you would expect, too (although the SQL
# involved is a little complex).
self.assertSequenceEqual(
Article.objects.exclude(publications=self.p2),
[self.a1],
)
def test_reverse_selects(self):
# Reverse m2m queries are supported (i.e., starting at the table that
# doesn't have a ManyToManyField).
python_journal = [self.p1]
self.assertSequenceEqual(
Publication.objects.filter(id__exact=self.p1.id), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(pk=self.p1.id), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(article__headline__startswith="NASA"),
[self.p4, self.p2, self.p2, self.p3, self.p1],
)
self.assertSequenceEqual(
Publication.objects.filter(article__id__exact=self.a1.id), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(article__pk=self.a1.id), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(article=self.a1.id), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(article=self.a1), python_journal
)
self.assertSequenceEqual(
Publication.objects.filter(article__in=[self.a1.id, self.a2.id]).distinct(),
[self.p4, self.p2, self.p3, self.p1],
)
self.assertSequenceEqual(
Publication.objects.filter(article__in=[self.a1.id, self.a2]).distinct(),
[self.p4, self.p2, self.p3, self.p1],
)
self.assertSequenceEqual(
Publication.objects.filter(article__in=[self.a1, self.a2]).distinct(),
[self.p4, self.p2, self.p3, self.p1],
)
def test_delete(self):
# If we delete a Publication, its Articles won't be able to access it.
self.p1.delete()
self.assertSequenceEqual(
Publication.objects.all(),
[self.p4, self.p2, self.p3],
)
self.assertSequenceEqual(self.a1.publications.all(), [])
# If we delete an Article, its Publications won't be able to access it.
self.a2.delete()
self.assertSequenceEqual(
Article.objects.all(),
[self.a1, self.a3, self.a4],
)
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
def test_bulk_delete(self):
# Bulk delete some Publications - references to deleted publications should go
Publication.objects.filter(title__startswith="Science").delete()
self.assertSequenceEqual(
Publication.objects.all(),
[self.p4, self.p1],
)
self.assertSequenceEqual(
Article.objects.all(),
[self.a1, self.a3, self.a2, self.a4],
)
self.assertSequenceEqual(
self.a2.publications.all(),
[self.p4, self.p1],
)
# Bulk delete some articles - references to deleted objects should go
q = Article.objects.filter(headline__startswith="Django")
self.assertSequenceEqual(q, [self.a1])
q.delete()
# After the delete, the QuerySet cache needs to be cleared,
# and the referenced objects should be gone
self.assertSequenceEqual(q, [])
self.assertSequenceEqual(self.p1.article_set.all(), [self.a2])
def test_remove(self):
# Removing publication from an article:
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a2, self.a4],
)
self.a4.publications.remove(self.p2)
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a2],
)
self.assertSequenceEqual(self.a4.publications.all(), [])
# And from the other end
self.p2.article_set.remove(self.a3)
self.assertSequenceEqual(self.p2.article_set.all(), [self.a2])
self.assertSequenceEqual(self.a3.publications.all(), [])
def test_set(self):
self.p2.article_set.set([self.a4, self.a3])
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
self.assertSequenceEqual(self.a4.publications.all(), [self.p2])
self.a4.publications.set([self.p3.id])
self.assertSequenceEqual(self.p2.article_set.all(), [self.a3])
self.assertSequenceEqual(self.a4.publications.all(), [self.p3])
self.p2.article_set.set([])
self.assertSequenceEqual(self.p2.article_set.all(), [])
self.a4.publications.set([])
self.assertSequenceEqual(self.a4.publications.all(), [])
self.p2.article_set.set([self.a4, self.a3], clear=True)
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
self.assertSequenceEqual(self.a4.publications.all(), [self.p2])
self.a4.publications.set([self.p3.id], clear=True)
self.assertSequenceEqual(self.p2.article_set.all(), [self.a3])
self.assertSequenceEqual(self.a4.publications.all(), [self.p3])
self.p2.article_set.set([], clear=True)
self.assertSequenceEqual(self.p2.article_set.all(), [])
self.a4.publications.set([], clear=True)
self.assertSequenceEqual(self.a4.publications.all(), [])
def test_set_existing_different_type(self):
# Existing many-to-many relations remain the same for values provided
# with a different type.
ids = set(
Publication.article_set.through.objects.filter(
article__in=[self.a4, self.a3],
publication=self.p2,
).values_list("id", flat=True)
)
self.p2.article_set.set([str(self.a4.pk), str(self.a3.pk)])
new_ids = set(
Publication.article_set.through.objects.filter(
publication=self.p2,
).values_list("id", flat=True)
)
self.assertEqual(ids, new_ids)
def test_assign_forward(self):
msg = (
"Direct assignment to the reverse side of a many-to-many set is "
"prohibited. Use article_set.set() instead."
)
with self.assertRaisesMessage(TypeError, msg):
self.p2.article_set = [self.a4, self.a3]
def test_assign_reverse(self):
msg = (
"Direct assignment to the forward side of a many-to-many "
"set is prohibited. Use publications.set() instead."
)
with self.assertRaisesMessage(TypeError, msg):
self.a1.publications = [self.p1, self.p2]
def test_assign(self):
# Relation sets can be assigned using set().
self.p2.article_set.set([self.a4, self.a3])
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
self.assertSequenceEqual(self.a4.publications.all(), [self.p2])
self.a4.publications.set([self.p3.id])
self.assertSequenceEqual(self.p2.article_set.all(), [self.a3])
self.assertSequenceEqual(self.a4.publications.all(), [self.p3])
# An alternate to calling clear() is to set an empty set.
self.p2.article_set.set([])
self.assertSequenceEqual(self.p2.article_set.all(), [])
self.a4.publications.set([])
self.assertSequenceEqual(self.a4.publications.all(), [])
def test_assign_ids(self):
# Relation sets can also be set using primary key values
self.p2.article_set.set([self.a4.id, self.a3.id])
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
self.assertSequenceEqual(self.a4.publications.all(), [self.p2])
self.a4.publications.set([self.p3.id])
self.assertSequenceEqual(self.p2.article_set.all(), [self.a3])
self.assertSequenceEqual(self.a4.publications.all(), [self.p3])
def test_forward_assign_with_queryset(self):
# Querysets used in m2m assignments are pre-evaluated so their value
# isn't affected by the clearing operation in ManyRelatedManager.set()
# (#19816).
self.a1.publications.set([self.p1, self.p2])
qs = self.a1.publications.filter(title="The Python Journal")
self.a1.publications.set(qs)
self.assertEqual(1, self.a1.publications.count())
self.assertEqual(1, qs.count())
def test_reverse_assign_with_queryset(self):
# Querysets used in M2M assignments are pre-evaluated so their value
# isn't affected by the clearing operation in ManyRelatedManager.set()
# (#19816).
self.p1.article_set.set([self.a1, self.a2])
qs = self.p1.article_set.filter(
headline="Django lets you build web apps easily"
)
self.p1.article_set.set(qs)
self.assertEqual(1, self.p1.article_set.count())
self.assertEqual(1, qs.count())
def test_clear(self):
# Relation sets can be cleared:
self.p2.article_set.clear()
self.assertSequenceEqual(self.p2.article_set.all(), [])
self.assertSequenceEqual(self.a4.publications.all(), [])
# And you can clear from the other end
self.p2.article_set.add(self.a3, self.a4)
self.assertSequenceEqual(
self.p2.article_set.all(),
[self.a3, self.a4],
)
self.assertSequenceEqual(self.a4.publications.all(), [self.p2])
self.a4.publications.clear()
self.assertSequenceEqual(self.a4.publications.all(), [])
self.assertSequenceEqual(self.p2.article_set.all(), [self.a3])
def test_clear_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertSequenceEqual(a4.publications.all(), [self.p2])
a4.publications.clear()
self.assertSequenceEqual(a4.publications.all(), [])
def test_remove_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertSequenceEqual(a4.publications.all(), [self.p2])
a4.publications.remove(self.p2)
self.assertSequenceEqual(a4.publications.all(), [])
def test_add_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertEqual(a4.publications.count(), 1)
a4.publications.add(self.p1)
self.assertEqual(a4.publications.count(), 2)
def test_create_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertSequenceEqual(a4.publications.all(), [self.p2])
p5 = a4.publications.create(title="Django beats")
self.assertCountEqual(a4.publications.all(), [self.p2, p5])
def test_set_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertEqual(a4.publications.count(), 1)
a4.publications.set([self.p2, self.p1])
self.assertEqual(a4.publications.count(), 2)
a4.publications.set([self.p1])
self.assertEqual(a4.publications.count(), 1)
def test_add_then_remove_after_prefetch(self):
a4 = Article.objects.prefetch_related("publications").get(id=self.a4.id)
self.assertEqual(a4.publications.count(), 1)
a4.publications.add(self.p1)
self.assertEqual(a4.publications.count(), 2)
a4.publications.remove(self.p1)
self.assertSequenceEqual(a4.publications.all(), [self.p2])
def test_inherited_models_selects(self):
"""
#24156 - Objects from child models where the parent's m2m field uses
related_name='+' should be retrieved correctly.
"""
a = InheritedArticleA.objects.create()
b = InheritedArticleB.objects.create()
a.publications.add(self.p1, self.p2)
self.assertSequenceEqual(
a.publications.all(),
[self.p2, self.p1],
)
self.assertSequenceEqual(b.publications.all(), [])
b.publications.add(self.p3)
self.assertSequenceEqual(
a.publications.all(),
[self.p2, self.p1],
)
self.assertSequenceEqual(b.publications.all(), [self.p3])
def test_custom_default_manager_exists_count(self):
a5 = Article.objects.create(headline="deleted")
a5.publications.add(self.p2)
with self.assertNumQueries(2) as ctx:
self.assertEqual(
self.p2.article_set.count(), self.p2.article_set.all().count()
)
self.assertIn("JOIN", ctx.captured_queries[0]["sql"])
with self.assertNumQueries(2) as ctx:
self.assertEqual(
self.p3.article_set.exists(), self.p3.article_set.all().exists()
)
self.assertIn("JOIN", ctx.captured_queries[0]["sql"])
def test_get_prefetch_queryset_warning(self):
articles = Article.objects.all()
msg = (
"get_prefetch_queryset() is deprecated. Use get_prefetch_querysets() "
"instead."
)
with self.assertWarnsMessage(RemovedInDjango60Warning, msg):
self.a1.publications.get_prefetch_queryset(articles)
def test_get_prefetch_querysets_invalid_querysets_length(self):
articles = Article.objects.all()
msg = (
"querysets argument of get_prefetch_querysets() should have a length of 1."
)
with self.assertRaisesMessage(ValueError, msg):
self.a1.publications.get_prefetch_querysets(
instances=articles,
querysets=[Publication.objects.all(), Publication.objects.all()],
)
class ManyToManyQueryTests(TestCase):
"""
SQL is optimized to reference the through table without joining against the
related table when using count() and exists() functions on a queryset for
many to many relations. The optimization applies to the case where there
are no filters.
"""
@classmethod
def setUpTestData(cls):
cls.article = Article.objects.create(
headline="Django lets you build Web apps easily"
)
cls.nullable_target_article = NullableTargetArticle.objects.create(
headline="The python is good"
)
NullablePublicationThrough.objects.create(
article=cls.nullable_target_article, publication=None
)
@skipUnlessDBFeature("supports_foreign_keys")
def test_count_join_optimization(self):
with self.assertNumQueries(1) as ctx:
self.article.publications.count()
self.assertNotIn("JOIN", ctx.captured_queries[0]["sql"])
with self.assertNumQueries(1) as ctx:
self.article.publications.count()
self.assertNotIn("JOIN", ctx.captured_queries[0]["sql"])
self.assertEqual(self.nullable_target_article.publications.count(), 0)
def test_count_join_optimization_disabled(self):
with (
mock.patch.object(connection.features, "supports_foreign_keys", False),
self.assertNumQueries(1) as ctx,
):
self.article.publications.count()
self.assertIn("JOIN", ctx.captured_queries[0]["sql"])
@skipUnlessDBFeature("supports_foreign_keys")
def test_exists_join_optimization(self):
with self.assertNumQueries(1) as ctx:
self.article.publications.exists()
self.assertNotIn("JOIN", ctx.captured_queries[0]["sql"])
self.article.publications.prefetch_related()
with self.assertNumQueries(1) as ctx:
self.article.publications.exists()
self.assertNotIn("JOIN", ctx.captured_queries[0]["sql"])
self.assertIs(self.nullable_target_article.publications.exists(), False)
def test_exists_join_optimization_disabled(self):
with (
mock.patch.object(connection.features, "supports_foreign_keys", False),
self.assertNumQueries(1) as ctx,
):
self.article.publications.exists()
self.assertIn("JOIN", ctx.captured_queries[0]["sql"])
def test_prefetch_related_no_queries_optimization_disabled(self):
qs = Article.objects.prefetch_related("publications")
article = qs.get()
with self.assertNumQueries(0):
article.publications.count()
with self.assertNumQueries(0):
article.publications.exists()