mirror of https://github.com/django/django.git
279 lines
11 KiB
Python
279 lines
11 KiB
Python
from django.core.exceptions import FieldError
|
|
from django.test import TestCase
|
|
|
|
from .models import (
|
|
BigChild, Child, ChildProxy, Primary, RefreshPrimaryProxy, Secondary,
|
|
ShadowChild,
|
|
)
|
|
|
|
|
|
class AssertionMixin:
|
|
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 = len(obj.get_deferred_fields())
|
|
self.assertEqual(count, num)
|
|
|
|
|
|
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.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)
|
|
# You can use 'pk' with reverse foreign key lookups.
|
|
# The related_id is always set even if it's not fetched from the DB,
|
|
# so pk and related_id are not deferred.
|
|
self.assert_delayed(self.s1.primary_set.all().only('pk')[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)
|
|
|
|
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(Primary.objects.defer("name").values()[0], {
|
|
"id": self.p1.id,
|
|
"name": "p1",
|
|
"value": "xx",
|
|
"related_id": self.s1.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": self.s1.id,
|
|
})
|
|
|
|
def test_get(self):
|
|
# Using defer() and only() with get() is also valid.
|
|
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_select_related_raises_invalid_query(self):
|
|
msg = (
|
|
'Field Primary.related cannot be both deferred and traversed '
|
|
'using select_related at the same time.'
|
|
)
|
|
with self.assertRaisesMessage(FieldError, msg):
|
|
Primary.objects.defer("related").select_related("related")[0]
|
|
|
|
def test_only_select_related_raises_invalid_query(self):
|
|
msg = (
|
|
'Field Primary.related cannot be both deferred and traversed using '
|
|
'select_related at the same time.'
|
|
)
|
|
with self.assertRaisesMessage(FieldError, msg):
|
|
Primary.objects.only("name").select_related("related")[0]
|
|
|
|
def test_defer_foreign_keys_are_deferred_and_not_traversed(self):
|
|
# select_related() overrides defer().
|
|
with self.assertNumQueries(1):
|
|
obj = Primary.objects.defer("related").select_related()[0]
|
|
self.assert_delayed(obj, 1)
|
|
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).
|
|
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(), [
|
|
"p1", "a new 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=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")
|
|
|
|
def test_only_baseclass_when_subclass_has_no_added_fields(self):
|
|
# You can retrieve a single column on a base class with no fields
|
|
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, "c1")
|
|
self.assertEqual(obj.value, "foo")
|
|
|
|
def test_defer_of_overridden_scalar(self):
|
|
ShadowChild.objects.create()
|
|
obj = ShadowChild.objects.defer('name').get()
|
|
self.assertEqual(obj.name, 'adonis')
|
|
|
|
|
|
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")
|
|
|
|
def test_defer_subclass(self):
|
|
# You can defer a field on a subclass
|
|
obj = BigChild.objects.defer("other").get(name="b1")
|
|
self.assert_delayed(obj, 1)
|
|
self.assertEqual(obj.name, "b1")
|
|
self.assertEqual(obj.value, "foo")
|
|
self.assertEqual(obj.other, "bar")
|
|
|
|
def test_defer_subclass_both(self):
|
|
# Deferring fields from both superclass and subclass works.
|
|
obj = BigChild.objects.defer("other", "value").get(name="b1")
|
|
self.assert_delayed(obj, 2)
|
|
|
|
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="b1")
|
|
# when inherited model, its PK is also fetched, hence '4' deferred fields.
|
|
self.assert_delayed(obj, 4)
|
|
self.assertEqual(obj.name, "b1")
|
|
self.assertEqual(obj.value, "foo")
|
|
self.assertEqual(obj.other, "bar")
|
|
|
|
def test_only_subclass(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, "b1")
|
|
self.assertEqual(obj.value, "foo")
|
|
self.assertEqual(obj.other, "bar")
|
|
|
|
|
|
class TestDefer2(AssertionMixin, TestCase):
|
|
def test_defer_proxy(self):
|
|
"""
|
|
Ensure select_related together with only on a proxy model behaves
|
|
as expected. See #17876.
|
|
"""
|
|
related = Secondary.objects.create(first='x1', second='x2')
|
|
ChildProxy.objects.create(name='p1', value='xx', related=related)
|
|
children = ChildProxy.objects.all().select_related().only('id', 'name')
|
|
self.assertEqual(len(children), 1)
|
|
child = children[0]
|
|
self.assert_delayed(child, 2)
|
|
self.assertEqual(child.name, 'p1')
|
|
self.assertEqual(child.value, 'xx')
|
|
|
|
def test_defer_inheritance_pk_chaining(self):
|
|
"""
|
|
When an inherited model is fetched from the DB, its PK is also fetched.
|
|
When getting the PK of the parent model it is useful to use the already
|
|
fetched parent model PK if it happens to be available.
|
|
"""
|
|
s1 = Secondary.objects.create(first="x1", second="y1")
|
|
bc = BigChild.objects.create(name='b1', value='foo', related=s1, other='bar')
|
|
bc_deferred = BigChild.objects.only('name').get(pk=bc.pk)
|
|
with self.assertNumQueries(0):
|
|
bc_deferred.id
|
|
self.assertEqual(bc_deferred.pk, bc_deferred.id)
|
|
|
|
def test_eq(self):
|
|
s1 = Secondary.objects.create(first="x1", second="y1")
|
|
s1_defer = Secondary.objects.only('pk').get(pk=s1.pk)
|
|
self.assertEqual(s1, s1_defer)
|
|
self.assertEqual(s1_defer, s1)
|
|
|
|
def test_refresh_not_loading_deferred_fields(self):
|
|
s = Secondary.objects.create()
|
|
rf = Primary.objects.create(name='foo', value='bar', related=s)
|
|
rf2 = Primary.objects.only('related', 'value').get()
|
|
rf.name = 'new foo'
|
|
rf.value = 'new bar'
|
|
rf.save()
|
|
with self.assertNumQueries(1):
|
|
rf2.refresh_from_db()
|
|
self.assertEqual(rf2.value, 'new bar')
|
|
with self.assertNumQueries(1):
|
|
self.assertEqual(rf2.name, 'new foo')
|
|
|
|
def test_custom_refresh_on_deferred_loading(self):
|
|
s = Secondary.objects.create()
|
|
rf = RefreshPrimaryProxy.objects.create(name='foo', value='bar', related=s)
|
|
rf2 = RefreshPrimaryProxy.objects.only('related').get()
|
|
rf.name = 'new foo'
|
|
rf.value = 'new bar'
|
|
rf.save()
|
|
with self.assertNumQueries(1):
|
|
# Customized refresh_from_db() reloads all deferred fields on
|
|
# access of any of them.
|
|
self.assertEqual(rf2.name, 'new foo')
|
|
self.assertEqual(rf2.value, 'new bar')
|