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Diffstat (limited to 'tests/m2m_through/tests.py')
| -rw-r--r-- | tests/m2m_through/tests.py | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/tests/m2m_through/tests.py b/tests/m2m_through/tests.py new file mode 100644 index 0000000000..259dc68a0b --- /dev/null +++ b/tests/m2m_through/tests.py @@ -0,0 +1,345 @@ +from __future__ import absolute_import + +from datetime import datetime +from operator import attrgetter + +from django.test import TestCase + +from .models import (Person, Group, Membership, CustomMembership, + PersonSelfRefM2M, Friendship) + + +class M2mThroughTests(TestCase): + def setUp(self): + self.bob = Person.objects.create(name='Bob') + self.jim = Person.objects.create(name='Jim') + self.jane = Person.objects.create(name='Jane') + self.rock = Group.objects.create(name='Rock') + self.roll = Group.objects.create(name='Roll') + + def test_m2m_through(self): + # We start out by making sure that the Group 'rock' has no members. + self.assertQuerysetEqual( + self.rock.members.all(), + [] + ) + # To make Jim a member of Group Rock, simply create a Membership object. + m1 = Membership.objects.create(person=self.jim, group=self.rock) + # We can do the same for Jane and Rock. + m2 = Membership.objects.create(person=self.jane, group=self.rock) + # Let's check to make sure that it worked. Jane and Jim should be members of Rock. + self.assertQuerysetEqual( + self.rock.members.all(), [ + 'Jane', + 'Jim' + ], + attrgetter("name") + ) + # Now we can add a bunch more Membership objects to test with. + m3 = Membership.objects.create(person=self.bob, group=self.roll) + m4 = Membership.objects.create(person=self.jim, group=self.roll) + m5 = Membership.objects.create(person=self.jane, group=self.roll) + # We can get Jim's Group membership as with any ForeignKey. + self.assertQuerysetEqual( + self.jim.group_set.all(), [ + 'Rock', + 'Roll' + ], + attrgetter("name") + ) + # Querying the intermediary model works like normal. + self.assertEqual( + repr(Membership.objects.get(person=self.jane, group=self.rock)), + '<Membership: Jane is a member of Rock>' + ) + # It's not only get that works. Filter works like normal as well. + self.assertQuerysetEqual( + Membership.objects.filter(person=self.jim), [ + '<Membership: Jim is a member of Rock>', + '<Membership: Jim is a member of Roll>' + ] + ) + self.rock.members.clear() + # Now there will be no members of Rock. + self.assertQuerysetEqual( + self.rock.members.all(), + [] + ) + + + + def test_forward_descriptors(self): + # Due to complications with adding via an intermediary model, + # the add method is not provided. + self.assertRaises(AttributeError, lambda: self.rock.members.add(self.bob)) + # Create is also disabled as it suffers from the same problems as add. + self.assertRaises(AttributeError, lambda: self.rock.members.create(name='Anne')) + # Remove has similar complications, and is not provided either. + self.assertRaises(AttributeError, lambda: self.rock.members.remove(self.jim)) + + m1 = Membership.objects.create(person=self.jim, group=self.rock) + m2 = Membership.objects.create(person=self.jane, group=self.rock) + + # Here we back up the list of all members of Rock. + backup = list(self.rock.members.all()) + # ...and we verify that it has worked. + self.assertEqual( + [p.name for p in backup], + ['Jane', 'Jim'] + ) + # The clear function should still work. + self.rock.members.clear() + # Now there will be no members of Rock. + self.assertQuerysetEqual( + self.rock.members.all(), + [] + ) + + # Assignment should not work with models specifying a through model for many of + # the same reasons as adding. + self.assertRaises(AttributeError, setattr, self.rock, "members", backup) + # Let's re-save those instances that we've cleared. + m1.save() + m2.save() + # Verifying that those instances were re-saved successfully. + self.assertQuerysetEqual( + self.rock.members.all(),[ + 'Jane', + 'Jim' + ], + attrgetter("name") + ) + + def test_reverse_descriptors(self): + # Due to complications with adding via an intermediary model, + # the add method is not provided. + self.assertRaises(AttributeError, lambda: self.bob.group_set.add(self.rock)) + # Create is also disabled as it suffers from the same problems as add. + self.assertRaises(AttributeError, lambda: self.bob.group_set.create(name="funk")) + # Remove has similar complications, and is not provided either. + self.assertRaises(AttributeError, lambda: self.jim.group_set.remove(self.rock)) + + m1 = Membership.objects.create(person=self.jim, group=self.rock) + m2 = Membership.objects.create(person=self.jim, group=self.roll) + + # Here we back up the list of all of Jim's groups. + backup = list(self.jim.group_set.all()) + self.assertEqual( + [g.name for g in backup], + ['Rock', 'Roll'] + ) + # The clear function should still work. + self.jim.group_set.clear() + # Now Jim will be in no groups. + self.assertQuerysetEqual( + self.jim.group_set.all(), + [] + ) + # Assignment should not work with models specifying a through model for many of + # the same reasons as adding. + self.assertRaises(AttributeError, setattr, self.jim, "group_set", backup) + # Let's re-save those instances that we've cleared. + + m1.save() + m2.save() + # Verifying that those instances were re-saved successfully. + self.assertQuerysetEqual( + self.jim.group_set.all(),[ + 'Rock', + 'Roll' + ], + attrgetter("name") + ) + + def test_custom_tests(self): + # Let's see if we can query through our second relationship. + self.assertQuerysetEqual( + self.rock.custom_members.all(), + [] + ) + # We can query in the opposite direction as well. + self.assertQuerysetEqual( + self.bob.custom.all(), + [] + ) + + cm1 = CustomMembership.objects.create(person=self.bob, group=self.rock) + cm2 = CustomMembership.objects.create(person=self.jim, group=self.rock) + + # If we get the number of people in Rock, it should be both Bob and Jim. + self.assertQuerysetEqual( + self.rock.custom_members.all(),[ + 'Bob', + 'Jim' + ], + attrgetter("name") + ) + # Bob should only be in one custom group. + self.assertQuerysetEqual( + self.bob.custom.all(),[ + 'Rock' + ], + attrgetter("name") + ) + # Let's make sure our new descriptors don't conflict with the FK related_name. + self.assertQuerysetEqual( + self.bob.custom_person_related_name.all(),[ + '<CustomMembership: Bob is a member of Rock>' + ] + ) + + def test_self_referential_tests(self): + # Let's first create a person who has no friends. + tony = PersonSelfRefM2M.objects.create(name="Tony") + self.assertQuerysetEqual( + tony.friends.all(), + [] + ) + + chris = PersonSelfRefM2M.objects.create(name="Chris") + f = Friendship.objects.create(first=tony, second=chris, date_friended=datetime.now()) + + # Tony should now show that Chris is his friend. + self.assertQuerysetEqual( + tony.friends.all(),[ + 'Chris' + ], + attrgetter("name") + ) + # But we haven't established that Chris is Tony's Friend. + self.assertQuerysetEqual( + chris.friends.all(), + [] + ) + f2 = Friendship.objects.create(first=chris, second=tony, date_friended=datetime.now()) + + # Having added Chris as a friend, let's make sure that his friend set reflects + # that addition. + self.assertQuerysetEqual( + chris.friends.all(),[ + 'Tony' + ], + attrgetter("name") + ) + + # Chris gets mad and wants to get rid of all of his friends. + chris.friends.clear() + # Now he should not have any more friends. + self.assertQuerysetEqual( + chris.friends.all(), + [] + ) + # Since this isn't a symmetrical relation, Tony's friend link still exists. + self.assertQuerysetEqual( + tony.friends.all(),[ + 'Chris' + ], + attrgetter("name") + ) + + def test_query_tests(self): + m1 = Membership.objects.create(person=self.jim, group=self.rock) + m2 = Membership.objects.create(person=self.jane, group=self.rock) + m3 = Membership.objects.create(person=self.bob, group=self.roll) + m4 = Membership.objects.create(person=self.jim, group=self.roll) + m5 = Membership.objects.create(person=self.jane, group=self.roll) + + m2.invite_reason = "She was just awesome." + m2.date_joined = datetime(2006, 1, 1) + m2.save() + m3.date_joined = datetime(2004, 1, 1) + m3.save() + m5.date_joined = datetime(2004, 1, 1) + m5.save() + + # We can query for the related model by using its attribute name (members, in + # this case). + self.assertQuerysetEqual( + Group.objects.filter(members__name='Bob'),[ + 'Roll' + ], + attrgetter("name") + ) + + # To query through the intermediary model, we specify its model name. + # In this case, membership. + self.assertQuerysetEqual( + Group.objects.filter(membership__invite_reason="She was just awesome."),[ + 'Rock' + ], + attrgetter("name") + ) + + # If we want to query in the reverse direction by the related model, use its + # model name (group, in this case). + self.assertQuerysetEqual( + Person.objects.filter(group__name="Rock"),[ + 'Jane', + 'Jim' + ], + attrgetter("name") + ) + + cm1 = CustomMembership.objects.create(person=self.bob, group=self.rock) + cm2 = CustomMembership.objects.create(person=self.jim, group=self.rock) + # If the m2m field has specified a related_name, using that will work. + self.assertQuerysetEqual( + Person.objects.filter(custom__name="Rock"),[ + 'Bob', + 'Jim' + ], + attrgetter("name") + ) + + # To query through the intermediary model in the reverse direction, we again + # specify its model name (membership, in this case). + self.assertQuerysetEqual( + Person.objects.filter(membership__invite_reason="She was just awesome."),[ + 'Jane' + ], + attrgetter("name") + ) + + # Let's see all of the groups that Jane joined after 1 Jan 2005: + self.assertQuerysetEqual( + Group.objects.filter(membership__date_joined__gt=datetime(2005, 1, 1), membership__person=self.jane),[ + 'Rock' + ], + attrgetter("name") + ) + + # Queries also work in the reverse direction: Now let's see all of the people + # that have joined Rock since 1 Jan 2005: + self.assertQuerysetEqual( + Person.objects.filter(membership__date_joined__gt=datetime(2005, 1, 1), membership__group=self.rock),[ + 'Jane', + 'Jim' + ], + attrgetter("name") + ) + + # Conceivably, queries through membership could return correct, but non-unique + # querysets. To demonstrate this, we query for all people who have joined a + # group after 2004: + self.assertQuerysetEqual( + Person.objects.filter(membership__date_joined__gt=datetime(2004, 1, 1)),[ + 'Jane', + 'Jim', + 'Jim' + ], + attrgetter("name") + ) + + # Jim showed up twice, because he joined two groups ('Rock', and 'Roll'): + self.assertEqual( + [(m.person.name, m.group.name) for m in Membership.objects.filter(date_joined__gt=datetime(2004, 1, 1))], + [('Jane', 'Rock'), ('Jim', 'Rock'), ('Jim', 'Roll')] + ) + # QuerySet's distinct() method can correct this problem. + self.assertQuerysetEqual( + Person.objects.filter(membership__date_joined__gt=datetime(2004, 1, 1)).distinct(),[ + 'Jane', + 'Jim' + ], + attrgetter("name") + ) |