tests.py

import collections.abc
from datetime import datetime
from math import ceil
from operator import attrgetter
from unittest import skipUnless

from django.core.exceptions import FieldError
from django.db import connection, models
from django.db.models import (
    BooleanField,
    Case,
    Exists,
    ExpressionWrapper,
    F,
    Max,
    OuterRef,
    Q,
    Subquery,
    Value,
    When,
)
from django.db.models.functions import Abs, Cast, Length, Substr
from django.db.models.lookups import (
    Exact,
    GreaterThan,
    GreaterThanOrEqual,
    IsNull,
    LessThan,
    LessThanOrEqual,
)
from django.test import TestCase, skipUnlessDBFeature
from django.test.utils import isolate_apps, register_lookup

from .models import (
    Article,
    Author,
    Freebie,
    Game,
    IsNullWithNoneAsRHS,
    Player,
    Product,
    Season,
    Stock,
    Tag,
)


class LookupTests(TestCase):
    @classmethod
    def setUpTestData(cls):
        # Create a few Authors.
        cls.au1 = Author.objects.create(name="Author 1", alias="a1", bio="x" * 4001)
        cls.au2 = Author.objects.create(name="Author 2", alias="a2")
        # Create a few Articles.
        cls.a1 = Article.objects.create(
            headline="Article 1",
            pub_date=datetime(2005, 7, 26),
            author=cls.au1,
            slug="a1",
        )
        cls.a2 = Article.objects.create(
            headline="Article 2",
            pub_date=datetime(2005, 7, 27),
            author=cls.au1,
            slug="a2",
        )
        cls.a3 = Article.objects.create(
            headline="Article 3",
            pub_date=datetime(2005, 7, 27),
            author=cls.au1,
            slug="a3",
        )
        cls.a4 = Article.objects.create(
            headline="Article 4",
            pub_date=datetime(2005, 7, 28),
            author=cls.au1,
            slug="a4",
        )
        cls.a5 = Article.objects.create(
            headline="Article 5",
            pub_date=datetime(2005, 8, 1, 9, 0),
            author=cls.au2,
            slug="a5",
        )
        cls.a6 = Article.objects.create(
            headline="Article 6",
            pub_date=datetime(2005, 8, 1, 8, 0),
            author=cls.au2,
            slug="a6",
        )
        cls.a7 = Article.objects.create(
            headline="Article 7",
            pub_date=datetime(2005, 7, 27),
            author=cls.au2,
            slug="a7",
        )
        # Create a few Tags.
        cls.t1 = Tag.objects.create(name="Tag 1")
        cls.t1.articles.add(cls.a1, cls.a2, cls.a3)
        cls.t2 = Tag.objects.create(name="Tag 2")
        cls.t2.articles.add(cls.a3, cls.a4, cls.a5)
        cls.t3 = Tag.objects.create(name="Tag 3")
        cls.t3.articles.add(cls.a5, cls.a6, cls.a7)

    def test_exists(self):
        # We can use .exists() to check that there are some
        self.assertTrue(Article.objects.exists())
        for a in Article.objects.all():
            a.delete()
        # There should be none now!
        self.assertFalse(Article.objects.exists())

    def test_lookup_int_as_str(self):
        # Integer value can be queried using string
        self.assertSequenceEqual(
            Article.objects.filter(id__iexact=str(self.a1.id)),
            [self.a1],
        )

    @skipUnlessDBFeature("supports_date_lookup_using_string")
    def test_lookup_date_as_str(self):
        # A date lookup can be performed using a string search
        self.assertSequenceEqual(
            Article.objects.filter(pub_date__startswith="2005"),
            [self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )

    def test_iterator(self):
        # Each QuerySet gets iterator(), which is a generator that "lazily"
        # returns results using database-level iteration.
        self.assertIsInstance(Article.objects.iterator(), collections.abc.Iterator)

        self.assertQuerySetEqual(
            Article.objects.iterator(),
            [
                "Article 5",
                "Article 6",
                "Article 4",
                "Article 2",
                "Article 3",
                "Article 7",
                "Article 1",
            ],
            transform=attrgetter("headline"),
        )
        # iterator() can be used on any QuerySet.
        self.assertQuerySetEqual(
            Article.objects.filter(headline__endswith="4").iterator(),
            ["Article 4"],
            transform=attrgetter("headline"),
        )

    def test_count(self):
        # count() returns the number of objects matching search criteria.
        self.assertEqual(Article.objects.count(), 7)
        self.assertEqual(
            Article.objects.filter(pub_date__exact=datetime(2005, 7, 27)).count(), 3
        )
        self.assertEqual(
            Article.objects.filter(headline__startswith="Blah blah").count(), 0
        )

        # count() should respect sliced query sets.
        articles = Article.objects.all()
        self.assertEqual(articles.count(), 7)
        self.assertEqual(articles[:4].count(), 4)
        self.assertEqual(articles[1:100].count(), 6)
        self.assertEqual(articles[10:100].count(), 0)

        # Date and date/time lookups can also be done with strings.
        self.assertEqual(
            Article.objects.filter(pub_date__exact="2005-07-27 00:00:00").count(), 3
        )

    def test_in_bulk(self):
        # in_bulk() takes a list of IDs and returns a dictionary mapping IDs to objects.
        arts = Article.objects.in_bulk([self.a1.id, self.a2.id])
        self.assertEqual(arts[self.a1.id], self.a1)
        self.assertEqual(arts[self.a2.id], self.a2)
        self.assertEqual(
            Article.objects.in_bulk(),
            {
                self.a1.id: self.a1,
                self.a2.id: self.a2,
                self.a3.id: self.a3,
                self.a4.id: self.a4,
                self.a5.id: self.a5,
                self.a6.id: self.a6,
                self.a7.id: self.a7,
            },
        )
        self.assertEqual(Article.objects.in_bulk([self.a3.id]), {self.a3.id: self.a3})
        self.assertEqual(Article.objects.in_bulk({self.a3.id}), {self.a3.id: self.a3})
        self.assertEqual(
            Article.objects.in_bulk(frozenset([self.a3.id])), {self.a3.id: self.a3}
        )
        self.assertEqual(Article.objects.in_bulk((self.a3.id,)), {self.a3.id: self.a3})
        self.assertEqual(Article.objects.in_bulk([1000]), {})
        self.assertEqual(Article.objects.in_bulk([]), {})
        self.assertEqual(
            Article.objects.in_bulk(iter([self.a1.id])), {self.a1.id: self.a1}
        )
        self.assertEqual(Article.objects.in_bulk(iter([])), {})
        with self.assertRaises(TypeError):
            Article.objects.in_bulk(headline__startswith="Blah")

    def test_in_bulk_lots_of_ids(self):
        test_range = 2000
        max_query_params = connection.features.max_query_params
        expected_num_queries = (
            ceil(test_range / max_query_params) if max_query_params else 1
        )
        Author.objects.bulk_create(
            [Author() for i in range(test_range - Author.objects.count())]
        )
        authors = {author.pk: author for author in Author.objects.all()}
        with self.assertNumQueries(expected_num_queries):
            self.assertEqual(Author.objects.in_bulk(authors), authors)

    def test_in_bulk_with_field(self):
        self.assertEqual(
            Article.objects.in_bulk(
                [self.a1.slug, self.a2.slug, self.a3.slug], field_name="slug"
            ),
            {
                self.a1.slug: self.a1,
                self.a2.slug: self.a2,
                self.a3.slug: self.a3,
            },
        )

    def test_in_bulk_meta_constraint(self):
        season_2011 = Season.objects.create(year=2011)
        season_2012 = Season.objects.create(year=2012)
        Season.objects.create(year=2013)
        self.assertEqual(
            Season.objects.in_bulk(
                [season_2011.year, season_2012.year],
                field_name="year",
            ),
            {season_2011.year: season_2011, season_2012.year: season_2012},
        )

    def test_in_bulk_non_unique_field(self):
        msg = "in_bulk()'s field_name must be a unique field but 'author' isn't."
        with self.assertRaisesMessage(ValueError, msg):
            Article.objects.in_bulk([self.au1], field_name="author")

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_in_bulk_preserve_ordering(self):
        articles = (
            Article.objects.order_by("author_id", "-pub_date")
            .distinct("author_id")
            .in_bulk([self.au1.id, self.au2.id], field_name="author_id")
        )
        self.assertEqual(
            articles,
            {self.au1.id: self.a4, self.au2.id: self.a5},
        )

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_in_bulk_preserve_ordering_with_batch_size(self):
        old_max_query_params = connection.features.max_query_params
        connection.features.max_query_params = 1
        try:
            articles = (
                Article.objects.order_by("author_id", "-pub_date")
                .distinct("author_id")
                .in_bulk([self.au1.id, self.au2.id], field_name="author_id")
            )
            self.assertEqual(
                articles,
                {self.au1.id: self.a4, self.au2.id: self.a5},
            )
        finally:
            connection.features.max_query_params = old_max_query_params

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_in_bulk_distinct_field(self):
        self.assertEqual(
            Article.objects.order_by("headline")
            .distinct("headline")
            .in_bulk(
                [self.a1.headline, self.a5.headline],
                field_name="headline",
            ),
            {self.a1.headline: self.a1, self.a5.headline: self.a5},
        )

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_in_bulk_multiple_distinct_field(self):
        msg = "in_bulk()'s field_name must be a unique field but 'pub_date' isn't."
        with self.assertRaisesMessage(ValueError, msg):
            Article.objects.order_by("headline", "pub_date").distinct(
                "headline",
                "pub_date",
            ).in_bulk(field_name="pub_date")

    @isolate_apps("lookup")
    def test_in_bulk_non_unique_meta_constaint(self):
        class Model(models.Model):
            ean = models.CharField(max_length=100)
            brand = models.CharField(max_length=100)
            name = models.CharField(max_length=80)

            class Meta:
                constraints = [
                    models.UniqueConstraint(
                        fields=["ean"],
                        name="partial_ean_unique",
                        condition=models.Q(is_active=True),
                    ),
                    models.UniqueConstraint(
                        fields=["brand", "name"],
                        name="together_brand_name_unique",
                    ),
                ]

        msg = "in_bulk()'s field_name must be a unique field but '%s' isn't."
        for field_name in ["brand", "ean"]:
            with self.subTest(field_name=field_name):
                with self.assertRaisesMessage(ValueError, msg % field_name):
                    Model.objects.in_bulk(field_name=field_name)

    def test_in_bulk_sliced_queryset(self):
        msg = "Cannot use 'limit' or 'offset' with in_bulk()."
        with self.assertRaisesMessage(TypeError, msg):
            Article.objects.all()[0:5].in_bulk([self.a1.id, self.a2.id])

    def test_values(self):
        # values() returns a list of dictionaries instead of object instances --
        # and you can specify which fields you want to retrieve.
        self.assertSequenceEqual(
            Article.objects.values("headline"),
            [
                {"headline": "Article 5"},
                {"headline": "Article 6"},
                {"headline": "Article 4"},
                {"headline": "Article 2"},
                {"headline": "Article 3"},
                {"headline": "Article 7"},
                {"headline": "Article 1"},
            ],
        )
        self.assertSequenceEqual(
            Article.objects.filter(pub_date__exact=datetime(2005, 7, 27)).values("id"),
            [{"id": self.a2.id}, {"id": self.a3.id}, {"id": self.a7.id}],
        )
        self.assertSequenceEqual(
            Article.objects.values("id", "headline"),
            [
                {"id": self.a5.id, "headline": "Article 5"},
                {"id": self.a6.id, "headline": "Article 6"},
                {"id": self.a4.id, "headline": "Article 4"},
                {"id": self.a2.id, "headline": "Article 2"},
                {"id": self.a3.id, "headline": "Article 3"},
                {"id": self.a7.id, "headline": "Article 7"},
                {"id": self.a1.id, "headline": "Article 1"},
            ],
        )
        # You can use values() with iterator() for memory savings,
        # because iterator() uses database-level iteration.
        self.assertSequenceEqual(
            list(Article.objects.values("id", "headline").iterator()),
            [
                {"headline": "Article 5", "id": self.a5.id},
                {"headline": "Article 6", "id": self.a6.id},
                {"headline": "Article 4", "id": self.a4.id},
                {"headline": "Article 2", "id": self.a2.id},
                {"headline": "Article 3", "id": self.a3.id},
                {"headline": "Article 7", "id": self.a7.id},
                {"headline": "Article 1", "id": self.a1.id},
            ],
        )
        # The values() method works with "extra" fields specified in extra(select).
        self.assertSequenceEqual(
            Article.objects.extra(select={"id_plus_one": "id + 1"}).values(
                "id", "id_plus_one"
            ),
            [
                {"id": self.a5.id, "id_plus_one": self.a5.id + 1},
                {"id": self.a6.id, "id_plus_one": self.a6.id + 1},
                {"id": self.a4.id, "id_plus_one": self.a4.id + 1},
                {"id": self.a2.id, "id_plus_one": self.a2.id + 1},
                {"id": self.a3.id, "id_plus_one": self.a3.id + 1},
                {"id": self.a7.id, "id_plus_one": self.a7.id + 1},
                {"id": self.a1.id, "id_plus_one": self.a1.id + 1},
            ],
        )
        data = {
            "id_plus_one": "id+1",
            "id_plus_two": "id+2",
            "id_plus_three": "id+3",
            "id_plus_four": "id+4",
            "id_plus_five": "id+5",
            "id_plus_six": "id+6",
            "id_plus_seven": "id+7",
            "id_plus_eight": "id+8",
        }
        self.assertSequenceEqual(
            Article.objects.filter(id=self.a1.id).extra(select=data).values(*data),
            [
                {
                    "id_plus_one": self.a1.id + 1,
                    "id_plus_two": self.a1.id + 2,
                    "id_plus_three": self.a1.id + 3,
                    "id_plus_four": self.a1.id + 4,
                    "id_plus_five": self.a1.id + 5,
                    "id_plus_six": self.a1.id + 6,
                    "id_plus_seven": self.a1.id + 7,
                    "id_plus_eight": self.a1.id + 8,
                }
            ],
        )
        # You can specify fields from forward and reverse relations, just like filter().
        self.assertSequenceEqual(
            Article.objects.values("headline", "author__name"),
            [
                {"headline": self.a5.headline, "author__name": self.au2.name},
                {"headline": self.a6.headline, "author__name": self.au2.name},
                {"headline": self.a4.headline, "author__name": self.au1.name},
                {"headline": self.a2.headline, "author__name": self.au1.name},
                {"headline": self.a3.headline, "author__name": self.au1.name},
                {"headline": self.a7.headline, "author__name": self.au2.name},
                {"headline": self.a1.headline, "author__name": self.au1.name},
            ],
        )
        self.assertSequenceEqual(
            Author.objects.values("name", "article__headline").order_by(
                "name", "article__headline"
            ),
            [
                {"name": self.au1.name, "article__headline": self.a1.headline},
                {"name": self.au1.name, "article__headline": self.a2.headline},
                {"name": self.au1.name, "article__headline": self.a3.headline},
                {"name": self.au1.name, "article__headline": self.a4.headline},
                {"name": self.au2.name, "article__headline": self.a5.headline},
                {"name": self.au2.name, "article__headline": self.a6.headline},
                {"name": self.au2.name, "article__headline": self.a7.headline},
            ],
        )
        self.assertSequenceEqual(
            (
                Author.objects.values(
                    "name", "article__headline", "article__tag__name"
                ).order_by("name", "article__headline", "article__tag__name")
            ),
            [
                {
                    "name": self.au1.name,
                    "article__headline": self.a1.headline,
                    "article__tag__name": self.t1.name,
                },
                {
                    "name": self.au1.name,
                    "article__headline": self.a2.headline,
                    "article__tag__name": self.t1.name,
                },
                {
                    "name": self.au1.name,
                    "article__headline": self.a3.headline,
                    "article__tag__name": self.t1.name,
                },
                {
                    "name": self.au1.name,
                    "article__headline": self.a3.headline,
                    "article__tag__name": self.t2.name,
                },
                {
                    "name": self.au1.name,
                    "article__headline": self.a4.headline,
                    "article__tag__name": self.t2.name,
                },
                {
                    "name": self.au2.name,
                    "article__headline": self.a5.headline,
                    "article__tag__name": self.t2.name,
                },
                {
                    "name": self.au2.name,
                    "article__headline": self.a5.headline,
                    "article__tag__name": self.t3.name,
                },
                {
                    "name": self.au2.name,
                    "article__headline": self.a6.headline,
                    "article__tag__name": self.t3.name,
                },
                {
                    "name": self.au2.name,
                    "article__headline": self.a7.headline,
                    "article__tag__name": self.t3.name,
                },
            ],
        )
        # However, an exception FieldDoesNotExist will be thrown if you specify
        # a nonexistent field name in values() (a field that is neither in the
        # model nor in extra(select)).
        msg = (
            "Cannot resolve keyword 'id_plus_two' into field. Choices are: "
            "author, author_id, headline, id, id_plus_one, pub_date, slug, tag"
        )
        with self.assertRaisesMessage(FieldError, msg):
            Article.objects.extra(select={"id_plus_one": "id + 1"}).values(
                "id", "id_plus_two"
            )
        # If you don't specify field names to values(), all are returned.
        self.assertSequenceEqual(
            Article.objects.filter(id=self.a5.id).values(),
            [
                {
                    "id": self.a5.id,
                    "author_id": self.au2.id,
                    "headline": "Article 5",
                    "pub_date": datetime(2005, 8, 1, 9, 0),
                    "slug": "a5",
                }
            ],
        )

    def test_values_list(self):
        # values_list() is similar to values(), except that the results are
        # returned as a list of tuples, rather than a list of dictionaries.
        # Within each tuple, the order of the elements is the same as the order
        # of fields in the values_list() call.
        self.assertSequenceEqual(
            Article.objects.values_list("headline"),
            [
                ("Article 5",),
                ("Article 6",),
                ("Article 4",),
                ("Article 2",),
                ("Article 3",),
                ("Article 7",),
                ("Article 1",),
            ],
        )
        self.assertSequenceEqual(
            Article.objects.values_list("id").order_by("id"),
            [
                (self.a1.id,),
                (self.a2.id,),
                (self.a3.id,),
                (self.a4.id,),
                (self.a5.id,),
                (self.a6.id,),
                (self.a7.id,),
            ],
        )
        self.assertSequenceEqual(
            Article.objects.values_list("id", flat=True).order_by("id"),
            [
                self.a1.id,
                self.a2.id,
                self.a3.id,
                self.a4.id,
                self.a5.id,
                self.a6.id,
                self.a7.id,
            ],
        )
        self.assertSequenceEqual(
            Article.objects.extra(select={"id_plus_one": "id+1"})
            .order_by("id")
            .values_list("id"),
            [
                (self.a1.id,),
                (self.a2.id,),
                (self.a3.id,),
                (self.a4.id,),
                (self.a5.id,),
                (self.a6.id,),
                (self.a7.id,),
            ],
        )
        self.assertSequenceEqual(
            Article.objects.extra(select={"id_plus_one": "id+1"})
            .order_by("id")
            .values_list("id_plus_one", "id"),
            [
                (self.a1.id + 1, self.a1.id),
                (self.a2.id + 1, self.a2.id),
                (self.a3.id + 1, self.a3.id),
                (self.a4.id + 1, self.a4.id),
                (self.a5.id + 1, self.a5.id),
                (self.a6.id + 1, self.a6.id),
                (self.a7.id + 1, self.a7.id),
            ],
        )
        self.assertSequenceEqual(
            Article.objects.extra(select={"id_plus_one": "id+1"})
            .order_by("id")
            .values_list("id", "id_plus_one"),
            [
                (self.a1.id, self.a1.id + 1),
                (self.a2.id, self.a2.id + 1),
                (self.a3.id, self.a3.id + 1),
                (self.a4.id, self.a4.id + 1),
                (self.a5.id, self.a5.id + 1),
                (self.a6.id, self.a6.id + 1),
                (self.a7.id, self.a7.id + 1),
            ],
        )
        args = ("name", "article__headline", "article__tag__name")
        self.assertSequenceEqual(
            Author.objects.values_list(*args).order_by(*args),
            [
                (self.au1.name, self.a1.headline, self.t1.name),
                (self.au1.name, self.a2.headline, self.t1.name),
                (self.au1.name, self.a3.headline, self.t1.name),
                (self.au1.name, self.a3.headline, self.t2.name),
                (self.au1.name, self.a4.headline, self.t2.name),
                (self.au2.name, self.a5.headline, self.t2.name),
                (self.au2.name, self.a5.headline, self.t3.name),
                (self.au2.name, self.a6.headline, self.t3.name),
                (self.au2.name, self.a7.headline, self.t3.name),
            ],
        )
        with self.assertRaises(TypeError):
            Article.objects.values_list("id", "headline", flat=True)

    def test_get_next_previous_by(self):
        # Every DateField and DateTimeField creates get_next_by_FOO() and
        # get_previous_by_FOO() methods. In the case of identical date values,
        # these methods will use the ID as a fallback check. This guarantees
        # that no records are skipped or duplicated.
        self.assertEqual(repr(self.a1.get_next_by_pub_date()), "<Article: Article 2>")
        self.assertEqual(repr(self.a2.get_next_by_pub_date()), "<Article: Article 3>")
        self.assertEqual(
            repr(self.a2.get_next_by_pub_date(headline__endswith="6")),
            "<Article: Article 6>",
        )
        self.assertEqual(repr(self.a3.get_next_by_pub_date()), "<Article: Article 7>")
        self.assertEqual(repr(self.a4.get_next_by_pub_date()), "<Article: Article 6>")
        with self.assertRaises(Article.DoesNotExist):
            self.a5.get_next_by_pub_date()
        self.assertEqual(repr(self.a6.get_next_by_pub_date()), "<Article: Article 5>")
        self.assertEqual(repr(self.a7.get_next_by_pub_date()), "<Article: Article 4>")

        self.assertEqual(
            repr(self.a7.get_previous_by_pub_date()), "<Article: Article 3>"
        )
        self.assertEqual(
            repr(self.a6.get_previous_by_pub_date()), "<Article: Article 4>"
        )
        self.assertEqual(
            repr(self.a5.get_previous_by_pub_date()), "<Article: Article 6>"
        )
        self.assertEqual(
            repr(self.a4.get_previous_by_pub_date()), "<Article: Article 7>"
        )
        self.assertEqual(
            repr(self.a3.get_previous_by_pub_date()), "<Article: Article 2>"
        )
        self.assertEqual(
            repr(self.a2.get_previous_by_pub_date()), "<Article: Article 1>"
        )

    def test_escaping(self):
        # Underscores, percent signs and backslashes have special meaning in the
        # underlying SQL code, but Django handles the quoting of them automatically.
        a8 = Article.objects.create(
            headline="Article_ with underscore", pub_date=datetime(2005, 11, 20)
        )

        self.assertSequenceEqual(
            Article.objects.filter(headline__startswith="Article"),
            [a8, self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )
        self.assertSequenceEqual(
            Article.objects.filter(headline__startswith="Article_"),
            [a8],
        )
        a9 = Article.objects.create(
            headline="Article% with percent sign", pub_date=datetime(2005, 11, 21)
        )
        self.assertSequenceEqual(
            Article.objects.filter(headline__startswith="Article"),
            [a9, a8, self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )
        self.assertSequenceEqual(
            Article.objects.filter(headline__startswith="Article%"),
            [a9],
        )
        a10 = Article.objects.create(
            headline="Article with \\ backslash", pub_date=datetime(2005, 11, 22)
        )
        self.assertSequenceEqual(
            Article.objects.filter(headline__contains="\\"),
            [a10],
        )

    def test_exclude(self):
        pub_date = datetime(2005, 11, 20)
        a8 = Article.objects.create(
            headline="Article_ with underscore", pub_date=pub_date
        )
        a9 = Article.objects.create(
            headline="Article% with percent sign", pub_date=pub_date
        )
        a10 = Article.objects.create(
            headline="Article with \\ backslash", pub_date=pub_date
        )
        # exclude() is the opposite of filter() when doing lookups:
        self.assertSequenceEqual(
            Article.objects.filter(headline__contains="Article").exclude(
                headline__contains="with"
            ),
            [self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )
        self.assertSequenceEqual(
            Article.objects.exclude(headline__startswith="Article_"),
            [a10, a9, self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )
        self.assertSequenceEqual(
            Article.objects.exclude(headline="Article 7"),
            [a10, a9, a8, self.a5, self.a6, self.a4, self.a2, self.a3, self.a1],
        )

    def test_none(self):
        # none() returns a QuerySet that behaves like any other QuerySet object
        self.assertSequenceEqual(Article.objects.none(), [])
        self.assertSequenceEqual(
            Article.objects.none().filter(headline__startswith="Article"), []
        )
        self.assertSequenceEqual(
            Article.objects.filter(headline__startswith="Article").none(), []
        )
        self.assertEqual(Article.objects.none().count(), 0)
        self.assertEqual(
            Article.objects.none().update(headline="This should not take effect"), 0
        )
        self.assertSequenceEqual(list(Article.objects.none().iterator()), [])

    def test_in(self):
        self.assertSequenceEqual(
            Article.objects.exclude(id__in=[]),
            [self.a5, self.a6, self.a4, self.a2, self.a3, self.a7, self.a1],
        )

    def test_in_empty_list(self):
        self.assertSequenceEqual(Article.objects.filter(id__in=[]), [])

    def test_in_different_database(self):
        with self.assertRaisesMessage(
            ValueError,
            "Subqueries aren't allowed across different databases. Force the "
            "inner query to be evaluated using `list(inner_query)`.",
        ):
            list(Article.objects.filter(id__in=Article.objects.using("other").all()))

    def test_in_keeps_value_ordering(self):
        query = (
            Article.objects.filter(slug__in=["a%d" % i for i in range(1, 8)])
            .values("pk")
            .query
        )
        self.assertIn(" IN (a1, a2, a3, a4, a5, a6, a7) ", str(query))

    def test_in_ignore_none(self):
        with self.assertNumQueries(1) as ctx:
            self.assertSequenceEqual(
                Article.objects.filter(id__in=[None, self.a1.id]),
                [self.a1],
            )
        sql = ctx.captured_queries[0]["sql"]
        self.assertIn("IN (%s)" % self.a1.pk, sql)

    def test_in_ignore_solo_none(self):
        with self.assertNumQueries(0):
            self.assertSequenceEqual(Article.objects.filter(id__in=[None]), [])

    def test_in_ignore_none_with_unhashable_items(self):
        class UnhashableInt(int):
            __hash__ = None

        with self.assertNumQueries(1) as ctx:
            self.assertSequenceEqual(
                Article.objects.filter(id__in=[None, UnhashableInt(self.a1.id)]),
                [self.a1],
            )
        sql = ctx.captured_queries[0]["sql"]
        self.assertIn("IN (%s)" % self.a1.pk, sql)

    def test_error_messages(self):
        # Programming errors are pointed out with nice error messages
        with self.assertRaisesMessage(
            FieldError,
            "Cannot resolve keyword 'pub_date_year' into field. Choices are: "
            "author, author_id, headline, id, pub_date, slug, tag",
        ):
            Article.objects.filter(pub_date_year="2005").count()

    def test_unsupported_lookups(self):
        with self.assertRaisesMessage(
            FieldError,
            "Unsupported lookup 'starts' for CharField or join on the field "
            "not permitted, perhaps you meant startswith or istartswith?",
        ):
            Article.objects.filter(headline__starts="Article")

        with self.assertRaisesMessage(
            FieldError,
            "Unsupported lookup 'is_null' for DateTimeField or join on the field "
            "not permitted, perhaps you meant isnull?",
        ):
            Article.objects.filter(pub_date__is_null=True)

        with self.assertRaisesMessage(
            FieldError,
            "Unsupported lookup 'gobbledygook' for DateTimeField or join on the field "
            "not permitted.",
        ):
            Article.objects.filter(pub_date__gobbledygook="blahblah")

    def test_unsupported_lookups_custom_lookups(self):
        slug_field = Article._meta.get_field("slug")
        msg = (
            "Unsupported lookup 'lengtp' for SlugField or join on the field not "
            "permitted, perhaps you meant length?"
        )
        with self.assertRaisesMessage(FieldError, msg):
            with register_lookup(slug_field, Length):
                Article.objects.filter(slug__lengtp=20)

    def test_relation_nested_lookup_error(self):
        # An invalid nested lookup on a related field raises a useful error.
        msg = (
            "Unsupported lookup 'editor' for ForeignKey or join on the field not "
            "permitted."
        )
        with self.assertRaisesMessage(FieldError, msg):
            Article.objects.filter(author__editor__name="James")
        msg = (
            "Unsupported lookup 'foo' for ForeignKey or join on the field not "
            "permitted."
        )
        with self.assertRaisesMessage(FieldError, msg):
            Tag.objects.filter(articles__foo="bar")

    def test_unsupported_lookup_reverse_foreign_key(self):
        msg = (
            "Unsupported lookup 'title' for ManyToOneRel or join on the field not "
            "permitted."
        )
        with self.assertRaisesMessage(FieldError, msg):
            Author.objects.filter(article__title="Article 1")

    def test_unsupported_lookup_reverse_foreign_key_custom_lookups(self):
        msg = (
            "Unsupported lookup 'abspl' for ManyToOneRel or join on the field not "
            "permitted, perhaps you meant abspk?"
        )
        fk_field = Article._meta.get_field("author")
        with self.assertRaisesMessage(FieldError, msg):
            with register_lookup(fk_field, Abs, lookup_name="abspk"):
                Author.objects.filter(article__abspl=2)

    def test_filter_by_reverse_related_field_transform(self):
        fk_field = Article._meta.get_field("author")
        with register_lookup(fk_field, Abs):
            self.assertSequenceEqual(
                Author.objects.filter(article__abs=self.a1.pk), [self.au1]
            )

    def test_regex(self):
        # Create some articles with a bit more interesting headlines for
        # testing field lookups.
        Article.objects.all().delete()
        now = datetime.now()
        Article.objects.bulk_create(
            [
                Article(pub_date=now, headline="f"),
                Article(pub_date=now, headline="fo"),
                Article(pub_date=now, headline="foo"),
                Article(pub_date=now, headline="fooo"),
                Article(pub_date=now, headline="hey-Foo"),
                Article(pub_date=now, headline="bar"),
                Article(pub_date=now, headline="AbBa"),
                Article(pub_date=now, headline="baz"),
                Article(pub_date=now, headline="baxZ"),
            ]
        )
        # zero-or-more
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"fo*"),
            Article.objects.filter(headline__in=["f", "fo", "foo", "fooo"]),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"fo*"),
            Article.objects.filter(headline__in=["f", "fo", "foo", "fooo", "hey-Foo"]),
        )
        # one-or-more
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"fo+"),
            Article.objects.filter(headline__in=["fo", "foo", "fooo"]),
        )
        # wildcard
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"fooo?"),
            Article.objects.filter(headline__in=["foo", "fooo"]),
        )
        # leading anchor
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"^b"),
            Article.objects.filter(headline__in=["bar", "baxZ", "baz"]),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"^a"),
            Article.objects.filter(headline="AbBa"),
        )
        # trailing anchor
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"z$"),
            Article.objects.filter(headline="baz"),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"z$"),
            Article.objects.filter(headline__in=["baxZ", "baz"]),
        )
        # character sets
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"ba[rz]"),
            Article.objects.filter(headline__in=["bar", "baz"]),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"ba.[RxZ]"),
            Article.objects.filter(headline="baxZ"),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"ba[RxZ]"),
            Article.objects.filter(headline__in=["bar", "baxZ", "baz"]),
        )

        # and more articles:
        Article.objects.bulk_create(
            [
                Article(pub_date=now, headline="foobar"),
                Article(pub_date=now, headline="foobaz"),
                Article(pub_date=now, headline="ooF"),
                Article(pub_date=now, headline="foobarbaz"),
                Article(pub_date=now, headline="zoocarfaz"),
                Article(pub_date=now, headline="barfoobaz"),
                Article(pub_date=now, headline="bazbaRFOO"),
            ]
        )

        # alternation
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"oo(f|b)"),
            Article.objects.filter(
                headline__in=[
                    "barfoobaz",
                    "foobar",
                    "foobarbaz",
                    "foobaz",
                ]
            ),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"oo(f|b)"),
            Article.objects.filter(
                headline__in=[
                    "barfoobaz",
                    "foobar",
                    "foobarbaz",
                    "foobaz",
                    "ooF",
                ]
            ),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"^foo(f|b)"),
            Article.objects.filter(headline__in=["foobar", "foobarbaz", "foobaz"]),
        )

        # greedy matching
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"b.*az"),
            Article.objects.filter(
                headline__in=[
                    "barfoobaz",
                    "baz",
                    "bazbaRFOO",
                    "foobarbaz",
                    "foobaz",
                ]
            ),
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__iregex=r"b.*ar"),
            Article.objects.filter(
                headline__in=[
                    "bar",
                    "barfoobaz",
                    "bazbaRFOO",
                    "foobar",
                    "foobarbaz",
                ]
            ),
        )

    @skipUnlessDBFeature("supports_regex_backreferencing")
    def test_regex_backreferencing(self):
        # grouping and backreferences
        now = datetime.now()
        Article.objects.bulk_create(
            [
                Article(pub_date=now, headline="foobar"),
                Article(pub_date=now, headline="foobaz"),
                Article(pub_date=now, headline="ooF"),
                Article(pub_date=now, headline="foobarbaz"),
                Article(pub_date=now, headline="zoocarfaz"),
                Article(pub_date=now, headline="barfoobaz"),
                Article(pub_date=now, headline="bazbaRFOO"),
            ]
        )
        self.assertQuerySetEqual(
            Article.objects.filter(headline__regex=r"b(.).*b\1").values_list(
                "headline", flat=True
            ),
            ["barfoobaz", "bazbaRFOO", "foobarbaz"],
        )

    def test_regex_null(self):
        """
        A regex lookup does not fail on null/None values
        """
        Season.objects.create(year=2012, gt=None)
        self.assertQuerySetEqual(Season.objects.filter(gt__regex=r"^$"), [])

    def test_textfield_exact_null(self):
        with self.assertNumQueries(1) as ctx:
            self.assertSequenceEqual(Author.objects.filter(bio=None), [self.au2])
        # Columns with IS NULL condition are not wrapped (except PostgreSQL).
        bio_column = connection.ops.quote_name(Author._meta.get_field("bio").column)
        self.assertIn(f"{bio_column} IS NULL", ctx.captured_queries[0]["sql"])

    def test_regex_non_string(self):
        """
        A regex lookup does not fail on non-string fields
        """
        s = Season.objects.create(year=2013, gt=444)
        self.assertQuerySetEqual(Season.objects.filter(gt__regex=r"^444$"), [s])

    def test_regex_non_ascii(self):
        """
        A regex lookup does not trip on non-ASCII characters.
        """
        Player.objects.create(name="\u2660")
        Player.objects.get(name__regex="\u2660")

    def test_nonfield_lookups(self):
        """
        A lookup query containing non-fields raises the proper exception.
        """
        msg = (
            "Unsupported lookup 'blahblah' for CharField or join on the field not "
            "permitted."
        )
        with self.assertRaisesMessage(FieldError, msg):
            Article.objects.filter(headline__blahblah=99)
        with self.assertRaisesMessage(FieldError, msg):
            Article.objects.filter(headline__blahblah__exact=99)
        msg = (
            "Cannot resolve keyword 'blahblah' into field. Choices are: "
            "author, author_id, headline, id, pub_date, slug, tag"
        )
        with self.assertRaisesMessage(FieldError, msg):
            Article.objects.filter(blahblah=99)

    def test_lookup_collision(self):
        """
        Genuine field names don't collide with built-in lookup types
        ('year', 'gt', 'range', 'in' etc.) (#11670).
        """
        # 'gt' is used as a code number for the year, e.g. 111=>2009.
        season_2009 = Season.objects.create(year=2009, gt=111)
        season_2009.games.create(home="Houston Astros", away="St. Louis Cardinals")
        season_2010 = Season.objects.create(year=2010, gt=222)
        season_2010.games.create(home="Houston Astros", away="Chicago Cubs")
        season_2010.games.create(home="Houston Astros", away="Milwaukee Brewers")
        season_2010.games.create(home="Houston Astros", away="St. Louis Cardinals")
        season_2011 = Season.objects.create(year=2011, gt=333)
        season_2011.games.create(home="Houston Astros", away="St. Louis Cardinals")
        season_2011.games.create(home="Houston Astros", away="Milwaukee Brewers")
        hunter_pence = Player.objects.create(name="Hunter Pence")
        hunter_pence.games.set(Game.objects.filter(season__year__in=[2009, 2010]))
        pudge = Player.objects.create(name="Ivan Rodriquez")
        pudge.games.set(Game.objects.filter(season__year=2009))
        pedro_feliz = Player.objects.create(name="Pedro Feliz")
        pedro_feliz.games.set(Game.objects.filter(season__year__in=[2011]))
        johnson = Player.objects.create(name="Johnson")
        johnson.games.set(Game.objects.filter(season__year__in=[2011]))

        # Games in 2010
        self.assertEqual(Game.objects.filter(season__year=2010).count(), 3)
        self.assertEqual(Game.objects.filter(season__year__exact=2010).count(), 3)
        self.assertEqual(Game.objects.filter(season__gt=222).count(), 3)
        self.assertEqual(Game.objects.filter(season__gt__exact=222).count(), 3)

        # Games in 2011
        self.assertEqual(Game.objects.filter(season__year=2011).count(), 2)
        self.assertEqual(Game.objects.filter(season__year__exact=2011).count(), 2)
        self.assertEqual(Game.objects.filter(season__gt=333).count(), 2)
        self.assertEqual(Game.objects.filter(season__gt__exact=333).count(), 2)
        self.assertEqual(Game.objects.filter(season__year__gt=2010).count(), 2)
        self.assertEqual(Game.objects.filter(season__gt__gt=222).count(), 2)

        # Games played in 2010 and 2011
        self.assertEqual(Game.objects.filter(season__year__in=[2010, 2011]).count(), 5)
        self.assertEqual(Game.objects.filter(season__year__gt=2009).count(), 5)
        self.assertEqual(Game.objects.filter(season__gt__in=[222, 333]).count(), 5)
        self.assertEqual(Game.objects.filter(season__gt__gt=111).count(), 5)

        # Players who played in 2009
        self.assertEqual(
            Player.objects.filter(games__season__year=2009).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__year__exact=2009).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt=111).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt__exact=111).distinct().count(), 2
        )

        # Players who played in 2010
        self.assertEqual(
            Player.objects.filter(games__season__year=2010).distinct().count(), 1
        )
        self.assertEqual(
            Player.objects.filter(games__season__year__exact=2010).distinct().count(), 1
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt=222).distinct().count(), 1
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt__exact=222).distinct().count(), 1
        )

        # Players who played in 2011
        self.assertEqual(
            Player.objects.filter(games__season__year=2011).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__year__exact=2011).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt=333).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__year__gt=2010).distinct().count(), 2
        )
        self.assertEqual(
            Player.objects.filter(games__season__gt__gt=222).distinct().count(), 2
        )

    def test_chain_date_time_lookups(self):
        self.assertCountEqual(
            Article.objects.filter(pub_date__month__gt=7),
            [self.a5, self.a6],
        )
        self.assertCountEqual(
            Article.objects.filter(pub_date__day__gte=27),
            [self.a2, self.a3, self.a4, self.a7],
        )
        self.assertCountEqual(
            Article.objects.filter(pub_date__hour__lt=8),
            [self.a1, self.a2, self.a3, self.a4, self.a7],
        )
        self.assertCountEqual(
            Article.objects.filter(pub_date__minute__lte=0),
            [self.a1, self.a2, self.a3, self.a4, self.a5, self.a6, self.a7],
        )

    def test_exact_none_transform(self):
        """Transforms are used for __exact=None."""
        Season.objects.create(year=1, nulled_text_field="not null")
        self.assertFalse(Season.objects.filter(nulled_text_field__isnull=True))
        self.assertTrue(Season.objects.filter(nulled_text_field__nulled__isnull=True))
        self.assertTrue(Season.objects.filter(nulled_text_field__nulled__exact=None))
        self.assertTrue(Season.objects.filter(nulled_text_field__nulled=None))

    def test_exact_sliced_queryset_limit_one(self):
        self.assertCountEqual(
            Article.objects.filter(author=Author.objects.all()[:1]),
            [self.a1, self.a2, self.a3, self.a4],
        )

    def test_exact_sliced_queryset_limit_one_offset(self):
        self.assertCountEqual(
            Article.objects.filter(author=Author.objects.all()[1:2]),
            [self.a5, self.a6, self.a7],
        )

    def test_exact_sliced_queryset_not_limited_to_one(self):
        msg = (
            "The QuerySet value for an exact lookup must be limited to one "
            "result using slicing."
        )
        with self.assertRaisesMessage(ValueError, msg):
            list(Article.objects.filter(author=Author.objects.all()[:2]))
        with self.assertRaisesMessage(ValueError, msg):
            list(Article.objects.filter(author=Author.objects.all()[1:]))

    @skipUnless(connection.vendor == "mysql", "MySQL-specific workaround.")
    def test_exact_booleanfield(self):
        # MySQL ignores indexes with boolean fields unless they're compared
        # directly to a boolean value.
        product = Product.objects.create(name="Paper", qty_target=5000)
        Stock.objects.create(product=product, short=False, qty_available=5100)
        stock_1 = Stock.objects.create(product=product, short=True, qty_available=180)
        qs = Stock.objects.filter(short=True)
        self.assertSequenceEqual(qs, [stock_1])
        self.assertIn(
            "%s = True" % connection.ops.quote_name("short"),
            str(qs.query),
        )

    @skipUnless(connection.vendor == "mysql", "MySQL-specific workaround.")
    def test_exact_booleanfield_annotation(self):
        # MySQL ignores indexes with boolean fields unless they're compared
        # directly to a boolean value.
        qs = Author.objects.annotate(
            case=Case(
                When(alias="a1", then=True),
                default=False,
                output_field=BooleanField(),
            )
        ).filter(case=True)
        self.assertSequenceEqual(qs, [self.au1])
        self.assertIn(" = True", str(qs.query))

        qs = Author.objects.annotate(
            wrapped=ExpressionWrapper(Q(alias="a1"), output_field=BooleanField()),
        ).filter(wrapped=True)
        self.assertSequenceEqual(qs, [self.au1])
        self.assertIn(" = True", str(qs.query))
        # EXISTS(...) shouldn't be compared to a boolean value.
        qs = Author.objects.annotate(
            exists=Exists(Author.objects.filter(alias="a1", pk=OuterRef("pk"))),
        ).filter(exists=True)
        self.assertSequenceEqual(qs, [self.au1])
        self.assertNotIn(" = True", str(qs.query))

    def test_custom_field_none_rhs(self):
        """
        __exact=value is transformed to __isnull=True if Field.get_prep_value()
        converts value to None.
        """
        season = Season.objects.create(year=2012, nulled_text_field=None)
        self.assertTrue(
            Season.objects.filter(pk=season.pk, nulled_text_field__isnull=True)
        )
        self.assertTrue(Season.objects.filter(pk=season.pk, nulled_text_field=""))

    def test_pattern_lookups_with_substr(self):
        a = Author.objects.create(name="John Smith", alias="Johx")
        b = Author.objects.create(name="Rhonda Simpson", alias="sonx")
        tests = (
            ("startswith", [a]),
            ("istartswith", [a]),
            ("contains", [a, b]),
            ("icontains", [a, b]),
            ("endswith", [b]),
            ("iendswith", [b]),
        )
        for lookup, result in tests:
            with self.subTest(lookup=lookup):
                authors = Author.objects.filter(
                    **{"name__%s" % lookup: Substr("alias", 1, 3)}
                )
                self.assertCountEqual(authors, result)

    def test_custom_lookup_none_rhs(self):
        """Lookup.can_use_none_as_rhs=True allows None as a lookup value."""
        season = Season.objects.create(year=2012, nulled_text_field=None)
        query = Season.objects.get_queryset().query
        field = query.model._meta.get_field("nulled_text_field")
        self.assertIsInstance(
            query.build_lookup(["isnull_none_rhs"], field, None), IsNullWithNoneAsRHS
        )
        self.assertTrue(
            Season.objects.filter(pk=season.pk, nulled_text_field__isnull_none_rhs=True)
        )

    def test_exact_exists(self):
        qs = Article.objects.filter(pk=OuterRef("pk"))
        seasons = Season.objects.annotate(pk_exists=Exists(qs)).filter(
            pk_exists=Exists(qs),
        )
        self.assertCountEqual(seasons, Season.objects.all())

    def test_nested_outerref_lhs(self):
        tag = Tag.objects.create(name=self.au1.alias)
        tag.articles.add(self.a1)
        qs = Tag.objects.annotate(
            has_author_alias_match=Exists(
                Article.objects.annotate(
                    author_exists=Exists(
                        Author.objects.filter(alias=OuterRef(OuterRef("name")))
                    ),
                ).filter(author_exists=True)
            ),
        )
        self.assertEqual(qs.get(has_author_alias_match=True), tag)

    def test_exact_query_rhs_with_selected_columns(self):
        newest_author = Author.objects.create(name="Author 2")
        authors_max_ids = (
            Author.objects.filter(
                name="Author 2",
            )
            .values(
                "name",
            )
            .annotate(
                max_id=Max("id"),
            )
            .values("max_id")
        )
        authors = Author.objects.filter(id=authors_max_ids[:1])
        self.assertEqual(authors.get(), newest_author)

    def test_isnull_non_boolean_value(self):
        msg = "The QuerySet value for an isnull lookup must be True or False."
        tests = [
            Author.objects.filter(alias__isnull=1),
            Article.objects.filter(author__isnull=1),
            Season.objects.filter(games__isnull=1),
            Freebie.objects.filter(stock__isnull=1),
        ]
        for qs in tests:
            with self.subTest(qs=qs):
                with self.assertRaisesMessage(ValueError, msg):
                    qs.exists()

    def test_lookup_rhs(self):
        product = Product.objects.create(name="GME", qty_target=5000)
        stock_1 = Stock.objects.create(product=product, short=True, qty_available=180)
        stock_2 = Stock.objects.create(product=product, short=False, qty_available=5100)
        Stock.objects.create(product=product, short=False, qty_available=4000)
        self.assertCountEqual(
            Stock.objects.filter(short=Q(qty_available__lt=F("product__qty_target"))),
            [stock_1, stock_2],
        )
        self.assertCountEqual(
            Stock.objects.filter(
                short=ExpressionWrapper(
                    Q(qty_available__lt=F("product__qty_target")),
                    output_field=BooleanField(),
                )
            ),
            [stock_1, stock_2],
        )


class LookupQueryingTests(TestCase):
    @classmethod
    def setUpTestData(cls):
        cls.s1 = Season.objects.create(year=1942, gt=1942)
        cls.s2 = Season.objects.create(year=1842, gt=1942, nulled_text_field="text")
        cls.s3 = Season.objects.create(year=2042, gt=1942)
        Game.objects.create(season=cls.s1, home="NY", away="Boston")
        Game.objects.create(season=cls.s1, home="NY", away="Tampa")
        Game.objects.create(season=cls.s3, home="Boston", away="Tampa")

    def test_annotate(self):
        qs = Season.objects.annotate(equal=Exact(F("year"), 1942))
        self.assertCountEqual(
            qs.values_list("year", "equal"),
            ((1942, True), (1842, False), (2042, False)),
        )

    def test_alias(self):
        qs = Season.objects.alias(greater=GreaterThan(F("year"), 1910))
        self.assertCountEqual(qs.filter(greater=True), [self.s1, self.s3])

    def test_annotate_value_greater_than_value(self):
        qs = Season.objects.annotate(greater=GreaterThan(Value(40), Value(30)))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, True), (1842, True), (2042, True)),
        )

    def test_annotate_field_greater_than_field(self):
        qs = Season.objects.annotate(greater=GreaterThan(F("year"), F("gt")))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, False), (1842, False), (2042, True)),
        )

    def test_annotate_field_greater_than_value(self):
        qs = Season.objects.annotate(greater=GreaterThan(F("year"), Value(1930)))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, True), (1842, False), (2042, True)),
        )

    def test_annotate_field_greater_than_literal(self):
        qs = Season.objects.annotate(greater=GreaterThan(F("year"), 1930))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, True), (1842, False), (2042, True)),
        )

    def test_annotate_literal_greater_than_field(self):
        qs = Season.objects.annotate(greater=GreaterThan(1930, F("year")))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, False), (1842, True), (2042, False)),
        )

    def test_annotate_less_than_float(self):
        qs = Season.objects.annotate(lesser=LessThan(F("year"), 1942.1))
        self.assertCountEqual(
            qs.values_list("year", "lesser"),
            ((1942, True), (1842, True), (2042, False)),
        )

    def test_annotate_greater_than_or_equal(self):
        qs = Season.objects.annotate(greater=GreaterThanOrEqual(F("year"), 1942))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, True), (1842, False), (2042, True)),
        )

    def test_annotate_greater_than_or_equal_float(self):
        qs = Season.objects.annotate(greater=GreaterThanOrEqual(F("year"), 1942.1))
        self.assertCountEqual(
            qs.values_list("year", "greater"),
            ((1942, False), (1842, False), (2042, True)),
        )

    def test_combined_lookups(self):
        expression = Exact(F("year"), 1942) | GreaterThan(F("year"), 1942)
        qs = Season.objects.annotate(gte=expression)
        self.assertCountEqual(
            qs.values_list("year", "gte"),
            ((1942, True), (1842, False), (2042, True)),
        )

    def test_lookup_in_filter(self):
        qs = Season.objects.filter(GreaterThan(F("year"), 1910))
        self.assertCountEqual(qs, [self.s1, self.s3])

    def test_isnull_lookup_in_filter(self):
        self.assertSequenceEqual(
            Season.objects.filter(IsNull(F("nulled_text_field"), False)),
            [self.s2],
        )
        self.assertCountEqual(
            Season.objects.filter(IsNull(F("nulled_text_field"), True)),
            [self.s1, self.s3],
        )

    def test_filter_lookup_lhs(self):
        qs = Season.objects.annotate(before_20=LessThan(F("year"), 2000)).filter(
            before_20=LessThan(F("year"), 1900),
        )
        self.assertCountEqual(qs, [self.s2, self.s3])

    def test_filter_wrapped_lookup_lhs(self):
        qs = (
            Season.objects.annotate(
                before_20=ExpressionWrapper(
                    Q(year__lt=2000),
                    output_field=BooleanField(),
                )
            )
            .filter(before_20=LessThan(F("year"), 1900))
            .values_list("year", flat=True)
        )
        self.assertCountEqual(qs, [1842, 2042])

    def test_filter_exists_lhs(self):
        qs = Season.objects.annotate(
            before_20=Exists(
                Season.objects.filter(pk=OuterRef("pk"), year__lt=2000),
            )
        ).filter(before_20=LessThan(F("year"), 1900))
        self.assertCountEqual(qs, [self.s2, self.s3])

    def test_filter_subquery_lhs(self):
        qs = Season.objects.annotate(
            before_20=Subquery(
                Season.objects.filter(pk=OuterRef("pk")).values(
                    lesser=LessThan(F("year"), 2000),
                ),
            )
        ).filter(before_20=LessThan(F("year"), 1900))
        self.assertCountEqual(qs, [self.s2, self.s3])

    def test_combined_lookups_in_filter(self):
        expression = Exact(F("year"), 1942) | GreaterThan(F("year"), 1942)
        qs = Season.objects.filter(expression)
        self.assertCountEqual(qs, [self.s1, self.s3])

    def test_combined_annotated_lookups_in_filter(self):
        expression = Exact(F("year"), 1942) | GreaterThan(F("year"), 1942)
        qs = Season.objects.annotate(gte=expression).filter(gte=True)
        self.assertCountEqual(qs, [self.s1, self.s3])

    def test_combined_annotated_lookups_in_filter_false(self):
        expression = Exact(F("year"), 1942) | GreaterThan(F("year"), 1942)
        qs = Season.objects.annotate(gte=expression).filter(gte=False)
        self.assertSequenceEqual(qs, [self.s2])

    def test_lookup_in_order_by(self):
        qs = Season.objects.order_by(LessThan(F("year"), 1910), F("year"))
        self.assertSequenceEqual(qs, [self.s1, self.s3, self.s2])

    @skipUnlessDBFeature("supports_boolean_expr_in_select_clause")
    def test_aggregate_combined_lookup(self):
        expression = Cast(GreaterThan(F("year"), 1900), models.IntegerField())
        qs = Season.objects.aggregate(modern=models.Sum(expression))
        self.assertEqual(qs["modern"], 2)

    def test_conditional_expression(self):
        qs = Season.objects.annotate(
            century=Case(
                When(
                    GreaterThan(F("year"), 1900) & LessThanOrEqual(F("year"), 2000),
                    then=Value("20th"),
                ),
                default=Value("other"),
            )
        ).values("year", "century")
        self.assertCountEqual(
            qs,
            [
                {"year": 1942, "century": "20th"},
                {"year": 1842, "century": "other"},
                {"year": 2042, "century": "other"},
            ],
        )

    def test_multivalued_join_reuse(self):
        self.assertEqual(
            Season.objects.get(Exact(F("games__home"), "NY"), games__away="Boston"),
            self.s1,
        )
        self.assertEqual(
            Season.objects.get(Exact(F("games__home"), "NY") & Q(games__away="Boston")),
            self.s1,
        )
        self.assertEqual(
            Season.objects.get(
                Exact(F("games__home"), "NY") & Exact(F("games__away"), "Boston")
            ),
            self.s1,
        )