Refs #18586 -- Split up tests.defer.DeferTests.test_defer (89527576) · Commits · Dom Sekotill / django

tests/defer/tests.py

+112 −64

Original line number	Diff line number	Diff line
		@@ -6,155 +6,203 @@ from django.test import TestCase
		from .models import Secondary, Primary, Child, BigChild, ChildProxy, RefreshPrimaryProxy


		class DeferTests(TestCase):
		class AssertionMixin(object):
		def assert_delayed(self, obj, num):
		"""
		Instances with deferred fields look the same as normal instances when
		we examine attribute values. Therefore, this method returns the number
		of deferred fields on returned instances.
		"""
		count = 0
		for field in obj._meta.fields:
		if isinstance(obj.__class__.__dict__.get(field.attname),
		DeferredAttribute):
		if isinstance(obj.__class__.__dict__.get(field.attname), DeferredAttribute):
		count += 1
		self.assertEqual(count, num)

		def test_defer(self):
		# To all outward appearances, instances with deferred fields look the
		# same as normal instances when we examine attribute values. Therefore
		# we test for the number of deferred fields on returned instances (by
		# poking at the internals), as a way to observe what is going on.

		s1 = Secondary.objects.create(first="x1", second="y1")
		p1 = Primary.objects.create(name="p1", value="xx", related=s1)
		class DeferTests(AssertionMixin, TestCase):
		@classmethod
		def setUpTestData(cls):
		cls.s1 = Secondary.objects.create(first="x1", second="y1")
		cls.p1 = Primary.objects.create(name="p1", value="xx", related=cls.s1)

		def test_defer(self):
		qs = Primary.objects.all()

		self.assert_delayed(qs.defer("name")[0], 1)
		self.assert_delayed(qs.only("name")[0], 2)
		self.assert_delayed(qs.defer("name").get(pk=self.p1.pk), 1)
		self.assert_delayed(qs.defer("related__first")[0], 0)
		self.assert_delayed(qs.defer("name").defer("value")[0], 2)

		def test_only(self):
		qs = Primary.objects.all()
		self.assert_delayed(qs.only("name")[0], 2)
		self.assert_delayed(qs.only("name").get(pk=self.p1.pk), 2)
		self.assert_delayed(qs.only("name").only("value")[0], 2)
		self.assert_delayed(qs.only("related__first")[0], 2)
		# Using 'pk' with only() should result in 3 deferred fields, namely all
		# of them except the model's primary key see #15494
		self.assert_delayed(qs.only("pk")[0], 3)

		obj = qs.select_related().only("related__first")[0]
		self.assert_delayed(obj, 2)

		self.assertEqual(obj.related_id, s1.pk)

		# You can use 'pk' with reverse foreign key lookups.
		self.assert_delayed(s1.primary_set.all().only('pk')[0], 3)
		self.assert_delayed(self.s1.primary_set.all().only('pk')[0], 3)

		self.assert_delayed(qs.defer("name").extra(select={"a": 1})[0], 1)
		self.assert_delayed(qs.extra(select={"a": 1}).defer("name")[0], 1)
		self.assert_delayed(qs.defer("name").defer("value")[0], 2)
		self.assert_delayed(qs.only("name").only("value")[0], 2)
		self.assert_delayed(qs.only("name").defer("value")[0], 2)
		self.assert_delayed(qs.only("name", "value").defer("value")[0], 2)
		def test_defer_only_chaining(self):
		qs = Primary.objects.all()
		self.assert_delayed(qs.only("name", "value").defer("name")[0], 2)
		self.assert_delayed(qs.defer("name").only("value", "name")[0], 2)
		self.assert_delayed(qs.defer("name").only("value")[0], 2)
		self.assert_delayed(qs.only("name").defer("value")[0], 2)

		def test_defer_on_an_already_deferred_field(self):
		qs = Primary.objects.all()
		self.assert_delayed(qs.defer("name")[0], 1)
		self.assert_delayed(qs.defer("name").defer("name")[0], 1)

		obj = qs.only()[0]
		def test_defer_none_to_clear_deferred_set(self):
		qs = Primary.objects.all()
		self.assert_delayed(qs.defer("name", "value")[0], 2)
		self.assert_delayed(qs.defer(None)[0], 0)
		self.assert_delayed(qs.only("name").defer(None)[0], 0)

		def test_only_none_raises_error(self):
		msg = 'Cannot pass None as an argument to only().'
		with self.assertRaisesMessage(TypeError, msg):
		Primary.objects.only(None)

		def test_defer_extra(self):
		qs = Primary.objects.all()
		self.assert_delayed(qs.defer("name").extra(select={"a": 1})[0], 1)
		self.assert_delayed(qs.extra(select={"a": 1}).defer("name")[0], 1)

		def test_defer_values_does_not_defer(self):
		# User values() won't defer anything (you get the full list of
		# dictionaries back), but it still works.
		self.assertEqual(qs.defer("name").values()[0], {
		"id": p1.id,
		self.assertEqual(Primary.objects.defer("name").values()[0], {
		"id": self.p1.id,
		"name": "p1",
		"value": "xx",
		"related_id": s1.id,
		"related_id": self.s1.id,
		})
		self.assertEqual(qs.only("name").values()[0], {
		"id": p1.id,

		def test_only_values_does_not_defer(self):
		self.assertEqual(Primary.objects.only("name").values()[0], {
		"id": self.p1.id,
		"name": "p1",
		"value": "xx",
		"related_id": s1.id,
		"related_id": self.s1.id,
		})

		def test_get(self):
		# Using defer() and only() with get() is also valid.
		self.assert_delayed(qs.defer("name").get(pk=p1.pk), 1)
		self.assert_delayed(qs.only("name").get(pk=p1.pk), 2)
		qs = Primary.objects.all()
		self.assert_delayed(qs.defer("name").get(pk=self.p1.pk), 1)
		self.assert_delayed(qs.only("name").get(pk=self.p1.pk), 2)

		def test_defer_with_select_related(self):
		obj = Primary.objects.select_related().defer("related__first", "related__second")[0]
		self.assert_delayed(obj.related, 2)
		self.assert_delayed(obj, 0)

		def test_only_with_select_related(self):
		obj = Primary.objects.select_related().only("related__first")[0]
		self.assert_delayed(obj, 2)
		self.assert_delayed(obj.related, 1)
		self.assertEqual(obj.related_id, self.s1.pk)
		self.assertEqual(obj.name, "p1")

		def test_defer_selected_related_raises_invalid_query(self):
		# When we defer a field and also select_related it, the query is
		# invalid and raises an exception.
		with self.assertRaises(InvalidQuery):
		qs.only("name").select_related("related")[0]
		Primary.objects.defer("related").select_related("related")[0]

		def test_only_selected_related_raises_invalid_query(self):
		with self.assertRaises(InvalidQuery):
		qs.defer("related").select_related("related")[0]
		Primary.objects.only("name").select_related("related")[0]

		def test_defer_foreign_keys_are_deferred_and_not_traversed(self):
		# With a depth-based select_related, all deferred ForeignKeys are
		# deferred instead of traversed.
		with self.assertNumQueries(3):
		obj = qs.defer("related").select_related()[0]
		obj = Primary.objects.defer("related").select_related()[0]
		self.assert_delayed(obj, 1)
		self.assertEqual(obj.related.id, s1.pk)
		self.assertEqual(obj.related.id, self.s1.pk)

		def test_saving_object_with_deferred_field(self):
		# Saving models with deferred fields is possible (but inefficient,
		# since every field has to be retrieved first).
		obj = Primary.objects.defer("value").get(name="p1")
		Primary.objects.create(name="p2", value="xy", related=self.s1)
		obj = Primary.objects.defer("value").get(name="p2")
		obj.name = "a new name"
		obj.save()
		self.assertQuerysetEqual(
		Primary.objects.all(), [
		"a new name",
		"p1", "a new name",
		],
		lambda p: p.name
		lambda p: p.name,
		ordered=False,
		)

		def test_defer_baseclass_when_subclass_has_no_added_fields(self):
		# Regression for #10572 - A subclass with no extra fields can defer
		# fields from the base class
		Child.objects.create(name="c1", value="foo", related=s1)
		Child.objects.create(name="c1", value="foo", related=self.s1)
		# You can defer a field on a baseclass when the subclass has no fields
		obj = Child.objects.defer("value").get(name="c1")
		self.assert_delayed(obj, 1)
		self.assertEqual(obj.name, "c1")
		self.assertEqual(obj.value, "foo")
		obj.name = "c2"
		obj.save()

		def test_only_baseclass_when_subclass_has_no_added_fields(self):
		# You can retrieve a single column on a base class with no fields
		obj = Child.objects.only("name").get(name="c2")
		Child.objects.create(name="c1", value="foo", related=self.s1)
		obj = Child.objects.only("name").get(name="c1")
		# on an inherited model, its PK is also fetched, hence '3' deferred fields.
		self.assert_delayed(obj, 3)
		self.assertEqual(obj.name, "c2")
		self.assertEqual(obj.name, "c1")
		self.assertEqual(obj.value, "foo")
		obj.name = "cc"
		obj.save()

		BigChild.objects.create(name="b1", value="foo", related=s1, other="bar")

		class BigChildDeferTests(AssertionMixin, TestCase):
		@classmethod
		def setUpTestData(cls):
		cls.s1 = Secondary.objects.create(first="x1", second="y1")
		BigChild.objects.create(name="b1", value="foo", related=cls.s1, other="bar")

		def test_defer_baseclass_when_subclass_has_added_field(self):
		# You can defer a field on a baseclass
		obj = BigChild.objects.defer("value").get(name="b1")
		self.assert_delayed(obj, 1)
		self.assertEqual(obj.name, "b1")
		self.assertEqual(obj.value, "foo")
		self.assertEqual(obj.other, "bar")
		obj.name = "b2"
		obj.save()

		def test_defer_subclass(self):
		# You can defer a field on a subclass
		obj = BigChild.objects.defer("other").get(name="b2")
		obj = BigChild.objects.defer("other").get(name="b1")
		self.assert_delayed(obj, 1)
		self.assertEqual(obj.name, "b2")
		self.assertEqual(obj.name, "b1")
		self.assertEqual(obj.value, "foo")
		self.assertEqual(obj.other, "bar")
		obj.name = "b3"
		obj.save()

		def test_only_baseclass_when_subclass_has_added_field(self):
		# You can retrieve a single field on a baseclass
		obj = BigChild.objects.only("name").get(name="b3")
		obj = BigChild.objects.only("name").get(name="b1")
		# when inherited model, its PK is also fetched, hence '4' deferred fields.
		self.assert_delayed(obj, 4)
		self.assertEqual(obj.name, "b3")
		self.assertEqual(obj.name, "b1")
		self.assertEqual(obj.value, "foo")
		self.assertEqual(obj.other, "bar")
		obj.name = "b4"
		obj.save()

		# You can retrieve a single field on a baseclass
		obj = BigChild.objects.only("other").get(name="b4")
		def test_only_sublcass(self):
		# You can retrieve a single field on a subclass
		obj = BigChild.objects.only("other").get(name="b1")
		self.assert_delayed(obj, 4)
		self.assertEqual(obj.name, "b4")
		self.assertEqual(obj.name, "b1")
		self.assertEqual(obj.value, "foo")
		self.assertEqual(obj.other, "bar")
		obj.name = "bb"
		obj.save()


		class TestDefer2(AssertionMixin, TestCase):
		def test_defer_proxy(self):
		"""
		Ensure select_related together with only on a proxy model behaves