from django.db.models.signals import post_save, pre_save from django.test import TestCase from .models import Account, Employee, Person, Profile, ProxyEmployee class UpdateOnlyFieldsTests(TestCase): msg = ( "The following fields do not exist in this model, are m2m fields, or " "are non-concrete fields: %s" ) def test_update_fields_basic(self): s = Person.objects.create(name="Sara", gender="F") self.assertEqual(s.gender, "F") s.gender = "M" s.name = "Ian" s.save(update_fields=["name"]) s = Person.objects.get(pk=s.pk) self.assertEqual(s.gender, "F") self.assertEqual(s.name, "Ian") def test_update_fields_deferred(self): s = Person.objects.create(name="Sara", gender="F", pid=22) self.assertEqual(s.gender, "F") s1 = Person.objects.defer("gender", "pid").get(pk=s.pk) s1.name = "Emily" s1.gender = "M" with self.assertNumQueries(1): s1.save() s2 = Person.objects.get(pk=s1.pk) self.assertEqual(s2.name, "Emily") self.assertEqual(s2.gender, "M") def test_update_fields_only_1(self): s = Person.objects.create(name="Sara", gender="F") self.assertEqual(s.gender, "F") s1 = Person.objects.only("name").get(pk=s.pk) s1.name = "Emily" s1.gender = "M" with self.assertNumQueries(1): s1.save() s2 = Person.objects.get(pk=s1.pk) self.assertEqual(s2.name, "Emily") self.assertEqual(s2.gender, "M") def test_update_fields_only_2(self): s = Person.objects.create(name="Sara", gender="F", pid=22) self.assertEqual(s.gender, "F") s1 = Person.objects.only("name").get(pk=s.pk) s1.name = "Emily" s1.gender = "M" with self.assertNumQueries(2): s1.save(update_fields=["pid"]) s2 = Person.objects.get(pk=s1.pk) self.assertEqual(s2.name, "Sara") self.assertEqual(s2.gender, "F") def test_update_fields_only_repeated(self): s = Person.objects.create(name="Sara", gender="F") self.assertEqual(s.gender, "F") s1 = Person.objects.only("name").get(pk=s.pk) s1.gender = "M" with self.assertNumQueries(1): s1.save() # save() should not fetch deferred fields s1 = Person.objects.only("name").get(pk=s.pk) with self.assertNumQueries(1): s1.save() def test_update_fields_inheritance_defer(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) e1 = Employee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) e1 = Employee.objects.only("name").get(pk=e1.pk) e1.name = "Linda" with self.assertNumQueries(1): e1.save() self.assertEqual(Employee.objects.get(pk=e1.pk).name, "Linda") def test_update_fields_fk_defer(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) profile_receptionist = Profile.objects.create(name="Receptionist", salary=1000) e1 = Employee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) e1 = Employee.objects.only("profile").get(pk=e1.pk) e1.profile = profile_receptionist with self.assertNumQueries(1): e1.save() self.assertEqual(Employee.objects.get(pk=e1.pk).profile, profile_receptionist) e1.profile_id = profile_boss.pk with self.assertNumQueries(1): e1.save() self.assertEqual(Employee.objects.get(pk=e1.pk).profile, profile_boss) def test_select_related_only_interaction(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) e1 = Employee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) e1 = ( Employee.objects.only("profile__salary") .select_related("profile") .get(pk=e1.pk) ) profile_boss.name = "Clerk" profile_boss.salary = 1000 profile_boss.save() # The loaded salary of 3000 gets saved, the name of 'Clerk' isn't # overwritten. with self.assertNumQueries(1): e1.profile.save() reloaded_profile = Profile.objects.get(pk=profile_boss.pk) self.assertEqual(reloaded_profile.name, profile_boss.name) self.assertEqual(reloaded_profile.salary, 3000) def test_update_fields_m2m(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) e1 = Employee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) a1 = Account.objects.create(num=1) a2 = Account.objects.create(num=2) e1.accounts.set([a1, a2]) with self.assertRaisesMessage(ValueError, self.msg % "accounts"): e1.save(update_fields=["accounts"]) def test_update_fields_inheritance(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) profile_receptionist = Profile.objects.create(name="Receptionist", salary=1000) e1 = Employee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) e1.name = "Ian" e1.gender = "M" e1.save(update_fields=["name"]) e2 = Employee.objects.get(pk=e1.pk) self.assertEqual(e2.name, "Ian") self.assertEqual(e2.gender, "F") self.assertEqual(e2.profile, profile_boss) e2.profile = profile_receptionist e2.name = "Sara" e2.save(update_fields=["profile"]) e3 = Employee.objects.get(pk=e1.pk) self.assertEqual(e3.name, "Ian") self.assertEqual(e3.profile, profile_receptionist) with self.assertNumQueries(1): e3.profile = profile_boss e3.save(update_fields=["profile_id"]) e4 = Employee.objects.get(pk=e3.pk) self.assertEqual(e4.profile, profile_boss) self.assertEqual(e4.profile_id, profile_boss.pk) def test_update_fields_inheritance_with_proxy_model(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) profile_receptionist = Profile.objects.create(name="Receptionist", salary=1000) e1 = ProxyEmployee.objects.create( name="Sara", gender="F", employee_num=1, profile=profile_boss ) e1.name = "Ian" e1.gender = "M" e1.save(update_fields=["name"]) e2 = ProxyEmployee.objects.get(pk=e1.pk) self.assertEqual(e2.name, "Ian") self.assertEqual(e2.gender, "F") self.assertEqual(e2.profile, profile_boss) e2.profile = profile_receptionist e2.name = "Sara" e2.save(update_fields=["profile"]) e3 = ProxyEmployee.objects.get(pk=e1.pk) self.assertEqual(e3.name, "Ian") self.assertEqual(e3.profile, profile_receptionist) def test_update_fields_signals(self): p = Person.objects.create(name="Sara", gender="F") pre_save_data = [] def pre_save_receiver(**kwargs): pre_save_data.append(kwargs["update_fields"]) pre_save.connect(pre_save_receiver) post_save_data = [] def post_save_receiver(**kwargs): post_save_data.append(kwargs["update_fields"]) post_save.connect(post_save_receiver) p.save(update_fields=["name"]) self.assertEqual(len(pre_save_data), 1) self.assertEqual(len(pre_save_data[0]), 1) self.assertIn("name", pre_save_data[0]) self.assertEqual(len(post_save_data), 1) self.assertEqual(len(post_save_data[0]), 1) self.assertIn("name", post_save_data[0]) pre_save.disconnect(pre_save_receiver) post_save.disconnect(post_save_receiver) def test_update_fields_incorrect_params(self): s = Person.objects.create(name="Sara", gender="F") with self.assertRaisesMessage(ValueError, self.msg % "first_name"): s.save(update_fields=["first_name"]) # "name" is treated as an iterable so the output is something like # "n, a, m, e" but the order isn't deterministic. with self.assertRaisesMessage(ValueError, self.msg % ""): s.save(update_fields="name") def test_empty_update_fields(self): s = Person.objects.create(name="Sara", gender="F") pre_save_data = [] def pre_save_receiver(**kwargs): pre_save_data.append(kwargs["update_fields"]) pre_save.connect(pre_save_receiver) post_save_data = [] def post_save_receiver(**kwargs): post_save_data.append(kwargs["update_fields"]) post_save.connect(post_save_receiver) # Save is skipped. with self.assertNumQueries(0): s.save(update_fields=[]) # Signals were skipped, too... self.assertEqual(len(pre_save_data), 0) self.assertEqual(len(post_save_data), 0) pre_save.disconnect(pre_save_receiver) post_save.disconnect(post_save_receiver) def test_num_queries_inheritance(self): s = Employee.objects.create(name="Sara", gender="F") s.employee_num = 1 s.name = "Emily" with self.assertNumQueries(1): s.save(update_fields=["employee_num"]) s = Employee.objects.get(pk=s.pk) self.assertEqual(s.employee_num, 1) self.assertEqual(s.name, "Sara") s.employee_num = 2 s.name = "Emily" with self.assertNumQueries(1): s.save(update_fields=["name"]) s = Employee.objects.get(pk=s.pk) self.assertEqual(s.name, "Emily") self.assertEqual(s.employee_num, 1) # A little sanity check that we actually did updates... self.assertEqual(Employee.objects.count(), 1) self.assertEqual(Person.objects.count(), 1) with self.assertNumQueries(2): s.save(update_fields=["name", "employee_num"]) def test_update_non_concrete_field(self): profile_boss = Profile.objects.create(name="Boss", salary=3000) with self.assertRaisesMessage(ValueError, self.msg % "non_concrete"): profile_boss.save(update_fields=["non_concrete"])