1
0
mirror of https://github.com/django/django.git synced 2024-12-23 01:25:58 +00:00
django/tests/distinct_on_fields/tests.py

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

181 lines
7.4 KiB
Python
Raw Normal View History

from django.db import connection
from django.db.models import CharField, F, Max
from django.db.models.functions import Lower
from django.test import TestCase, skipUnlessDBFeature
from django.test.utils import register_lookup
from .models import Celebrity, Fan, Staff, StaffTag, Tag
@skipUnlessDBFeature("can_distinct_on_fields")
@skipUnlessDBFeature("supports_nullable_unique_constraints")
class DistinctOnTests(TestCase):
@classmethod
def setUpTestData(cls):
cls.t1 = Tag.objects.create(name="t1")
cls.t2 = Tag.objects.create(name="t2", parent=cls.t1)
cls.t3 = Tag.objects.create(name="t3", parent=cls.t1)
cls.t4 = Tag.objects.create(name="t4", parent=cls.t3)
cls.t5 = Tag.objects.create(name="t5", parent=cls.t3)
cls.p1_o1 = Staff.objects.create(id=1, name="p1", organisation="o1")
cls.p2_o1 = Staff.objects.create(id=2, name="p2", organisation="o1")
cls.p3_o1 = Staff.objects.create(id=3, name="p3", organisation="o1")
cls.p1_o2 = Staff.objects.create(id=4, name="p1", organisation="o2")
cls.p1_o1.coworkers.add(cls.p2_o1, cls.p3_o1)
cls.st1 = StaffTag.objects.create(staff=cls.p1_o1, tag=cls.t1)
StaffTag.objects.create(staff=cls.p1_o1, tag=cls.t1)
cls.celeb1 = Celebrity.objects.create(name="c1")
cls.celeb2 = Celebrity.objects.create(name="c2")
cls.fan1 = Fan.objects.create(fan_of=cls.celeb1)
cls.fan2 = Fan.objects.create(fan_of=cls.celeb1)
cls.fan3 = Fan.objects.create(fan_of=cls.celeb2)
def test_basic_distinct_on(self):
"""QuerySet.distinct('field', ...) works"""
# (qset, expected) tuples
qsets = (
(
Staff.objects.distinct().order_by("name"),
[self.p1_o1, self.p1_o2, self.p2_o1, self.p3_o1],
),
(
Staff.objects.distinct("name").order_by("name"),
[self.p1_o1, self.p2_o1, self.p3_o1],
),
(
Staff.objects.distinct("organisation").order_by("organisation", "name"),
[self.p1_o1, self.p1_o2],
),
(
Staff.objects.distinct("name", "organisation").order_by(
"name", "organisation"
),
[self.p1_o1, self.p1_o2, self.p2_o1, self.p3_o1],
),
(
Celebrity.objects.filter(fan__in=[self.fan1, self.fan2, self.fan3])
.distinct("name")
.order_by("name"),
[self.celeb1, self.celeb2],
),
# Does combining querysets work?
(
(
Celebrity.objects.filter(fan__in=[self.fan1, self.fan2])
2013-10-23 10:09:29 +00:00
.distinct("name")
.order_by("name")
| Celebrity.objects.filter(fan__in=[self.fan3])
.distinct("name")
.order_by("name")
),
[self.celeb1, self.celeb2],
),
(StaffTag.objects.distinct("staff", "tag"), [self.st1]),
(
Tag.objects.order_by("parent__pk", "pk").distinct("parent"),
(
[self.t2, self.t4, self.t1]
if connection.features.nulls_order_largest
else [self.t1, self.t2, self.t4]
),
),
(
StaffTag.objects.select_related("staff")
.distinct("staff__name")
.order_by("staff__name"),
[self.st1],
),
# Fetch the alphabetically first coworker for each worker
(
(
Staff.objects.distinct("id")
.order_by("id", "coworkers__name")
.values_list("id", "coworkers__name")
),
[(1, "p2"), (2, "p1"), (3, "p1"), (4, None)],
),
)
for qset, expected in qsets:
self.assertSequenceEqual(qset, expected)
self.assertEqual(qset.count(), len(expected))
# Combining queries with non-unique query is not allowed.
base_qs = Celebrity.objects.all()
msg = "Cannot combine a unique query with a non-unique query."
with self.assertRaisesMessage(TypeError, msg):
base_qs.distinct("id") & base_qs
# Combining queries with different distinct_fields is not allowed.
msg = "Cannot combine queries with different distinct fields."
with self.assertRaisesMessage(TypeError, msg):
base_qs.distinct("id") & base_qs.distinct("name")
# Test join unreffing
c1 = Celebrity.objects.distinct("greatest_fan__id", "greatest_fan__fan_of")
self.assertIn("OUTER JOIN", str(c1.query))
c2 = c1.distinct("pk")
self.assertNotIn("OUTER JOIN", str(c2.query))
def test_sliced_queryset(self):
msg = "Cannot create distinct fields once a slice has been taken."
with self.assertRaisesMessage(TypeError, msg):
Staff.objects.all()[0:5].distinct("name")
def test_transform(self):
new_name = self.t1.name.upper()
self.assertNotEqual(self.t1.name, new_name)
Tag.objects.create(name=new_name)
with register_lookup(CharField, Lower):
self.assertCountEqual(
Tag.objects.order_by().distinct("name__lower"),
[self.t1, self.t2, self.t3, self.t4, self.t5],
)
def test_distinct_not_implemented_checks(self):
# distinct + annotate not allowed
msg = "annotate() + distinct(fields) is not implemented."
with self.assertRaisesMessage(NotImplementedError, msg):
Celebrity.objects.annotate(Max("id")).distinct("id")[0]
with self.assertRaisesMessage(NotImplementedError, msg):
Celebrity.objects.distinct("id").annotate(Max("id"))[0]
# However this check is done only when the query executes, so you
# can use distinct() to remove the fields before execution.
Celebrity.objects.distinct("id").annotate(Max("id")).distinct()[0]
# distinct + aggregate not allowed
msg = "aggregate() + distinct(fields) not implemented."
with self.assertRaisesMessage(NotImplementedError, msg):
Celebrity.objects.distinct("id").aggregate(Max("id"))
def test_distinct_on_in_ordered_subquery(self):
qs = Staff.objects.distinct("name").order_by("name", "id")
qs = Staff.objects.filter(pk__in=qs).order_by("name")
self.assertSequenceEqual(qs, [self.p1_o1, self.p2_o1, self.p3_o1])
qs = Staff.objects.distinct("name").order_by("name", "-id")
qs = Staff.objects.filter(pk__in=qs).order_by("name")
self.assertSequenceEqual(qs, [self.p1_o2, self.p2_o1, self.p3_o1])
def test_distinct_on_get_ordering_preserved(self):
"""
Ordering shouldn't be cleared when distinct on fields are specified.
refs #25081
"""
staff = (
Staff.objects.distinct("name")
.order_by("name", "-organisation")
.get(name="p1")
)
self.assertEqual(staff.organisation, "o2")
def test_distinct_on_mixed_case_annotation(self):
qs = (
Staff.objects.annotate(
nAmEAlIaS=F("name"),
)
.distinct("nAmEAlIaS")
.order_by("nAmEAlIaS")
)
self.assertSequenceEqual(qs, [self.p1_o1, self.p2_o1, self.p3_o1])