django/tests/regressiontests/select_related_regress/tests.py

141 lines
6.4 KiB
Python

from __future__ import absolute_import
from django.test import TestCase
from .models import (Building, Child, Device, Port, Item, Country, Connection,
ClientStatus, State, Client, SpecialClient, TUser, Person, Student,
Organizer, Class, Enrollment)
class SelectRelatedRegressTests(TestCase):
def test_regression_7110(self):
"""
Regression test for bug #7110.
When using select_related(), we must query the
Device and Building tables using two different aliases (each) in order to
differentiate the start and end Connection fields. The net result is that
both the "connections = ..." queries here should give the same results
without pulling in more than the absolute minimum number of tables
(history has shown that it's easy to make a mistake in the implementation
and include some unnecessary bonus joins).
"""
b=Building.objects.create(name='101')
dev1=Device.objects.create(name="router", building=b)
dev2=Device.objects.create(name="switch", building=b)
dev3=Device.objects.create(name="server", building=b)
port1=Port.objects.create(port_number='4',device=dev1)
port2=Port.objects.create(port_number='7',device=dev2)
port3=Port.objects.create(port_number='1',device=dev3)
c1=Connection.objects.create(start=port1, end=port2)
c2=Connection.objects.create(start=port2, end=port3)
connections=Connection.objects.filter(start__device__building=b, end__device__building=b).order_by('id')
self.assertEqual([(c.id, unicode(c.start), unicode(c.end)) for c in connections],
[(c1.id, u'router/4', u'switch/7'), (c2.id, u'switch/7', u'server/1')])
connections=Connection.objects.filter(start__device__building=b, end__device__building=b).select_related().order_by('id')
self.assertEqual([(c.id, unicode(c.start), unicode(c.end)) for c in connections],
[(c1.id, u'router/4', u'switch/7'), (c2.id, u'switch/7', u'server/1')])
# This final query should only have seven tables (port, device and building
# twice each, plus connection once). Thus, 6 joins plus the FROM table.
self.assertEqual(str(connections.query).count(" JOIN "), 6)
def test_regression_8106(self):
"""
Regression test for bug #8106.
Same sort of problem as the previous test, but this time there are
more extra tables to pull in as part of the select_related() and some
of them could potentially clash (so need to be kept separate).
"""
us = TUser.objects.create(name="std")
usp = Person.objects.create(user=us)
uo = TUser.objects.create(name="org")
uop = Person.objects.create(user=uo)
s = Student.objects.create(person = usp)
o = Organizer.objects.create(person = uop)
c = Class.objects.create(org=o)
e = Enrollment.objects.create(std=s, cls=c)
e_related = Enrollment.objects.all().select_related()[0]
self.assertEqual(e_related.std.person.user.name, u"std")
self.assertEqual(e_related.cls.org.person.user.name, u"org")
def test_regression_8036(self):
"""
Regression test for bug #8036
the first related model in the tests below
("state") is empty and we try to select the more remotely related
state__country. The regression here was not skipping the empty column results
for country before getting status.
"""
australia = Country.objects.create(name='Australia')
active = ClientStatus.objects.create(name='active')
client = Client.objects.create(name='client', status=active)
self.assertEqual(client.status, active)
self.assertEqual(Client.objects.select_related()[0].status, active)
self.assertEqual(Client.objects.select_related('state')[0].status, active)
self.assertEqual(Client.objects.select_related('state', 'status')[0].status, active)
self.assertEqual(Client.objects.select_related('state__country')[0].status, active)
self.assertEqual(Client.objects.select_related('state__country', 'status')[0].status, active)
self.assertEqual(Client.objects.select_related('status')[0].status, active)
def test_multi_table_inheritance(self):
""" Exercising select_related() with multi-table model inheritance. """
c1 = Child.objects.create(name="child1", value=42)
i1 = Item.objects.create(name="item1", child=c1)
i2 = Item.objects.create(name="item2")
self.assertQuerysetEqual(
Item.objects.select_related("child").order_by("name"),
["<Item: item1>", "<Item: item2>"]
)
def test_regression_12851(self):
"""
Regression for #12851
Deferred fields are used correctly if you select_related a subset
of fields.
"""
australia = Country.objects.create(name='Australia')
active = ClientStatus.objects.create(name='active')
wa = State.objects.create(name="Western Australia", country=australia)
c1 = Client.objects.create(name='Brian Burke', state=wa, status=active)
burke = Client.objects.select_related('state').defer('state__name').get(name='Brian Burke')
self.assertEqual(burke.name, u'Brian Burke')
self.assertEqual(burke.state.name, u'Western Australia')
# Still works if we're dealing with an inherited class
sc1 = SpecialClient.objects.create(name='Troy Buswell', state=wa, status=active, value=42)
troy = SpecialClient.objects.select_related('state').defer('state__name').get(name='Troy Buswell')
self.assertEqual(troy.name, u'Troy Buswell')
self.assertEqual(troy.value, 42)
self.assertEqual(troy.state.name, u'Western Australia')
# Still works if we defer an attribute on the inherited class
troy = SpecialClient.objects.select_related('state').defer('value', 'state__name').get(name='Troy Buswell')
self.assertEqual(troy.name, u'Troy Buswell')
self.assertEqual(troy.value, 42)
self.assertEqual(troy.state.name, u'Western Australia')
# Also works if you use only, rather than defer
troy = SpecialClient.objects.select_related('state').only('name').get(name='Troy Buswell')
self.assertEqual(troy.name, u'Troy Buswell')
self.assertEqual(troy.value, 42)
self.assertEqual(troy.state.name, u'Western Australia')