django/tests/annotations/tests.py

import datetime
from decimal import Decimal

from django.core.exceptions import FieldDoesNotExist, FieldError
from django.db.models import (
    BooleanField,
    Case,
    CharField,
    Count,
    DateTimeField,
    DecimalField,
    Exists,
    ExpressionWrapper,
    F,
    FloatField,
    Func,
    IntegerField,
    Max,
    OuterRef,
    Q,
    Subquery,
    Sum,
    Value,
    When,
)
from django.db.models.expressions import RawSQL
from django.db.models.functions import (
    Cast,
    Coalesce,
    ExtractYear,
    Floor,
    Length,
    Lower,
    Trim,
)
from django.test import TestCase, skipUnlessDBFeature
from django.test.utils import register_lookup

from .models import (
    Author,
    Book,
    Company,
    DepartmentStore,
    Employee,
    Publisher,
    Store,
    Ticket,
)


class NonAggregateAnnotationTestCase(TestCase):
    @classmethod
    def setUpTestData(cls):
        cls.a1 = Author.objects.create(name="Adrian Holovaty", age=34)
        cls.a2 = Author.objects.create(name="Jacob Kaplan-Moss", age=35)
        cls.a3 = Author.objects.create(name="Brad Dayley", age=45)
        cls.a4 = Author.objects.create(name="James Bennett", age=29)
        cls.a5 = Author.objects.create(name="Jeffrey Forcier", age=37)
        cls.a6 = Author.objects.create(name="Paul Bissex", age=29)
        cls.a7 = Author.objects.create(name="Wesley J. Chun", age=25)
        cls.a8 = Author.objects.create(name="Peter Norvig", age=57)
        cls.a9 = Author.objects.create(name="Stuart Russell", age=46)
        cls.a1.friends.add(cls.a2, cls.a4)
        cls.a2.friends.add(cls.a1, cls.a7)
        cls.a4.friends.add(cls.a1)
        cls.a5.friends.add(cls.a6, cls.a7)
        cls.a6.friends.add(cls.a5, cls.a7)
        cls.a7.friends.add(cls.a2, cls.a5, cls.a6)
        cls.a8.friends.add(cls.a9)
        cls.a9.friends.add(cls.a8)

        cls.p1 = Publisher.objects.create(name="Apress", num_awards=3)
        cls.p2 = Publisher.objects.create(name="Sams", num_awards=1)
        cls.p3 = Publisher.objects.create(name="Prentice Hall", num_awards=7)
        cls.p4 = Publisher.objects.create(name="Morgan Kaufmann", num_awards=9)
        cls.p5 = Publisher.objects.create(name="Jonno's House of Books", num_awards=0)

        cls.b1 = Book.objects.create(
            isbn="159059725",
            name="The Definitive Guide to Django: Web Development Done Right",
            pages=447,
            rating=4.5,
            price=Decimal("30.00"),
            contact=cls.a1,
            publisher=cls.p1,
            pubdate=datetime.date(2007, 12, 6),
        )
        cls.b2 = Book.objects.create(
            isbn="067232959",
            name="Sams Teach Yourself Django in 24 Hours",
            pages=528,
            rating=3.0,
            price=Decimal("23.09"),
            contact=cls.a3,
            publisher=cls.p2,
            pubdate=datetime.date(2008, 3, 3),
        )
        cls.b3 = Book.objects.create(
            isbn="159059996",
            name="Practical Django Projects",
            pages=300,
            rating=4.0,
            price=Decimal("29.69"),
            contact=cls.a4,
            publisher=cls.p1,
            pubdate=datetime.date(2008, 6, 23),
        )
        cls.b4 = Book.objects.create(
            isbn="013235613",
            name="Python Web Development with Django",
            pages=350,
            rating=4.0,
            price=Decimal("29.69"),
            contact=cls.a5,
            publisher=cls.p3,
            pubdate=datetime.date(2008, 11, 3),
        )
        cls.b5 = Book.objects.create(
            isbn="013790395",
            name="Artificial Intelligence: A Modern Approach",
            pages=1132,
            rating=4.0,
            price=Decimal("82.80"),
            contact=cls.a8,
            publisher=cls.p3,
            pubdate=datetime.date(1995, 1, 15),
        )
        cls.b6 = Book.objects.create(
            isbn="155860191",
            name=(
                "Paradigms of Artificial Intelligence Programming: Case Studies in "
                "Common Lisp"
            ),
            pages=946,
            rating=5.0,
            price=Decimal("75.00"),
            contact=cls.a8,
            publisher=cls.p4,
            pubdate=datetime.date(1991, 10, 15),
        )
        cls.b1.authors.add(cls.a1, cls.a2)
        cls.b2.authors.add(cls.a3)
        cls.b3.authors.add(cls.a4)
        cls.b4.authors.add(cls.a5, cls.a6, cls.a7)
        cls.b5.authors.add(cls.a8, cls.a9)
        cls.b6.authors.add(cls.a8)

        cls.s1 = Store.objects.create(
            name="Amazon.com",
            original_opening=datetime.datetime(1994, 4, 23, 9, 17, 42),
            friday_night_closing=datetime.time(23, 59, 59),
        )
        cls.s2 = Store.objects.create(
            name="Books.com",
            original_opening=datetime.datetime(2001, 3, 15, 11, 23, 37),
            friday_night_closing=datetime.time(23, 59, 59),
        )
        cls.s3 = Store.objects.create(
            name="Mamma and Pappa's Books",
            original_opening=datetime.datetime(1945, 4, 25, 16, 24, 14),
            friday_night_closing=datetime.time(21, 30),
        )
        cls.s1.books.add(cls.b1, cls.b2, cls.b3, cls.b4, cls.b5, cls.b6)
        cls.s2.books.add(cls.b1, cls.b3, cls.b5, cls.b6)
        cls.s3.books.add(cls.b3, cls.b4, cls.b6)

    def test_basic_annotation(self):
        books = Book.objects.annotate(is_book=Value(1))
        for book in books:
            self.assertEqual(book.is_book, 1)

    def test_basic_f_annotation(self):
        books = Book.objects.annotate(another_rating=F("rating"))
        for book in books:
            self.assertEqual(book.another_rating, book.rating)

    def test_joined_annotation(self):
        books = Book.objects.select_related("publisher").annotate(
            num_awards=F("publisher__num_awards")
        )
        for book in books:
            self.assertEqual(book.num_awards, book.publisher.num_awards)

    def test_joined_transformed_annotation(self):
        Employee.objects.bulk_create(
            [
                Employee(
                    first_name="John",
                    last_name="Doe",
                    age=18,
                    store=self.s1,
                    salary=15000,
                ),
                Employee(
                    first_name="Jane",
                    last_name="Jones",
                    age=30,
                    store=self.s2,
                    salary=30000,
                ),
                Employee(
                    first_name="Jo",
                    last_name="Smith",
                    age=55,
                    store=self.s3,
                    salary=50000,
                ),
            ]
        )
        employees = Employee.objects.annotate(
            store_opened_year=F("store__original_opening__year"),
        )
        for employee in employees:
            self.assertEqual(
                employee.store_opened_year,
                employee.store.original_opening.year,
            )

    def test_custom_transform_annotation(self):
        with register_lookup(DecimalField, Floor):
            books = Book.objects.annotate(floor_price=F("price__floor"))

        self.assertCountEqual(
            books.values_list("pk", "floor_price"),
            [
                (self.b1.pk, 30),
                (self.b2.pk, 23),
                (self.b3.pk, 29),
                (self.b4.pk, 29),
                (self.b5.pk, 82),
                (self.b6.pk, 75),
            ],
        )

    def test_chaining_transforms(self):
        Company.objects.create(name=" Django Software Foundation  ")
        Company.objects.create(name="Yahoo")
        with register_lookup(CharField, Trim), register_lookup(CharField, Length):
            for expr in [Length("name__trim"), F("name__trim__length")]:
                with self.subTest(expr=expr):
                    self.assertCountEqual(
                        Company.objects.annotate(length=expr).values("name", "length"),
                        [
                            {"name": " Django Software Foundation  ", "length": 26},
                            {"name": "Yahoo", "length": 5},
                        ],
                    )

    def test_mixed_type_annotation_date_interval(self):
        active = datetime.datetime(2015, 3, 20, 14, 0, 0)
        duration = datetime.timedelta(hours=1)
        expires = datetime.datetime(2015, 3, 20, 14, 0, 0) + duration
        Ticket.objects.create(active_at=active, duration=duration)
        t = Ticket.objects.annotate(
            expires=ExpressionWrapper(
                F("active_at") + F("duration"), output_field=DateTimeField()
            )
        ).first()
        self.assertEqual(t.expires, expires)

    def test_mixed_type_annotation_numbers(self):
        test = self.b1
        b = Book.objects.annotate(
            combined=ExpressionWrapper(
                F("pages") + F("rating"), output_field=IntegerField()
            )
        ).get(isbn=test.isbn)
        combined = int(test.pages + test.rating)
        self.assertEqual(b.combined, combined)

    def test_empty_expression_annotation(self):
        books = Book.objects.annotate(
            selected=ExpressionWrapper(Q(pk__in=[]), output_field=BooleanField())
        )
        self.assertEqual(len(books), Book.objects.count())
        self.assertTrue(all(not book.selected for book in books))

        books = Book.objects.annotate(
            selected=ExpressionWrapper(
                Q(pk__in=Book.objects.none()), output_field=BooleanField()
            )
        )
        self.assertEqual(len(books), Book.objects.count())
        self.assertTrue(all(not book.selected for book in books))

    def test_full_expression_annotation(self):
        books = Book.objects.annotate(
            selected=ExpressionWrapper(~Q(pk__in=[]), output_field=BooleanField()),
        )
        self.assertEqual(len(books), Book.objects.count())
        self.assertTrue(all(book.selected for book in books))

    def test_full_expression_wrapped_annotation(self):
        books = Book.objects.annotate(
            selected=Coalesce(~Q(pk__in=[]), True),
        )
        self.assertEqual(len(books), Book.objects.count())
        self.assertTrue(all(book.selected for book in books))

    def test_full_expression_annotation_with_aggregation(self):
        qs = Book.objects.filter(isbn="159059725").annotate(
            selected=ExpressionWrapper(~Q(pk__in=[]), output_field=BooleanField()),
            rating_count=Count("rating"),
        )
        self.assertEqual([book.rating_count for book in qs], [1])

    def test_aggregate_over_full_expression_annotation(self):
        qs = Book.objects.annotate(
            selected=ExpressionWrapper(~Q(pk__in=[]), output_field=BooleanField()),
        ).aggregate(selected__sum=Sum(Cast("selected", IntegerField())))
        self.assertEqual(qs["selected__sum"], Book.objects.count())

    def test_empty_queryset_annotation(self):
        qs = Author.objects.annotate(empty=Subquery(Author.objects.values("id").none()))
        self.assertIsNone(qs.first().empty)

    def test_annotate_with_aggregation(self):
        books = Book.objects.annotate(is_book=Value(1), rating_count=Count("rating"))
        for book in books:
            self.assertEqual(book.is_book, 1)
            self.assertEqual(book.rating_count, 1)

    def test_combined_expression_annotation_with_aggregation(self):
        book = Book.objects.annotate(
            combined=ExpressionWrapper(
                Value(3) * Value(4), output_field=IntegerField()
            ),
            rating_count=Count("rating"),
        ).first()
        self.assertEqual(book.combined, 12)
        self.assertEqual(book.rating_count, 1)

    def test_combined_f_expression_annotation_with_aggregation(self):
        book = (
            Book.objects.filter(isbn="159059725")
            .annotate(
                combined=ExpressionWrapper(
                    F("price") * F("pages"), output_field=FloatField()
                ),
                rating_count=Count("rating"),
            )
            .first()
        )
        self.assertEqual(book.combined, 13410.0)
        self.assertEqual(book.rating_count, 1)

    @skipUnlessDBFeature("supports_boolean_expr_in_select_clause")
    def test_q_expression_annotation_with_aggregation(self):
        book = (
            Book.objects.filter(isbn="159059725")
            .annotate(
                isnull_pubdate=ExpressionWrapper(
                    Q(pubdate__isnull=True),
                    output_field=BooleanField(),
                ),
                rating_count=Count("rating"),
            )
            .first()
        )
        self.assertIs(book.isnull_pubdate, False)
        self.assertEqual(book.rating_count, 1)

    @skipUnlessDBFeature("supports_boolean_expr_in_select_clause")
    def test_grouping_by_q_expression_annotation(self):
        authors = (
            Author.objects.annotate(
                under_40=ExpressionWrapper(Q(age__lt=40), output_field=BooleanField()),
            )
            .values("under_40")
            .annotate(
                count_id=Count("id"),
            )
            .values("under_40", "count_id")
        )
        self.assertCountEqual(
            authors,
            [
                {"under_40": False, "count_id": 3},
                {"under_40": True, "count_id": 6},
            ],
        )

    def test_aggregate_over_annotation(self):
        agg = Author.objects.annotate(other_age=F("age")).aggregate(
            otherage_sum=Sum("other_age")
        )
        other_agg = Author.objects.aggregate(age_sum=Sum("age"))
        self.assertEqual(agg["otherage_sum"], other_agg["age_sum"])

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_distinct_on_with_annotation(self):
        store = Store.objects.create(
            name="test store",
            original_opening=datetime.datetime.now(),
            friday_night_closing=datetime.time(21, 00, 00),
        )
        names = [
            "Theodore Roosevelt",
            "Eleanor Roosevelt",
            "Franklin Roosevelt",
            "Ned Stark",
            "Catelyn Stark",
        ]
        for name in names:
            Employee.objects.create(
                store=store,
                first_name=name.split()[0],
                last_name=name.split()[1],
                age=30,
                salary=2000,
            )

        people = Employee.objects.annotate(
            name_lower=Lower("last_name"),
        ).distinct("name_lower")

        self.assertEqual({p.last_name for p in people}, {"Stark", "Roosevelt"})
        self.assertEqual(len(people), 2)

        people2 = Employee.objects.annotate(
            test_alias=F("store__name"),
        ).distinct("test_alias")
        self.assertEqual(len(people2), 1)

        lengths = (
            Employee.objects.annotate(
                name_len=Length("first_name"),
            )
            .distinct("name_len")
            .values_list("name_len", flat=True)
        )
        self.assertCountEqual(lengths, [3, 7, 8])

    def test_filter_annotation(self):
        books = Book.objects.annotate(is_book=Value(1)).filter(is_book=1)
        for book in books:
            self.assertEqual(book.is_book, 1)

    def test_filter_annotation_with_f(self):
        books = Book.objects.annotate(other_rating=F("rating")).filter(other_rating=3.5)
        for book in books:
            self.assertEqual(book.other_rating, 3.5)

    def test_filter_annotation_with_double_f(self):
        books = Book.objects.annotate(other_rating=F("rating")).filter(
            other_rating=F("rating")
        )
        for book in books:
            self.assertEqual(book.other_rating, book.rating)

    def test_filter_agg_with_double_f(self):
        books = Book.objects.annotate(sum_rating=Sum("rating")).filter(
            sum_rating=F("sum_rating")
        )
        for book in books:
            self.assertEqual(book.sum_rating, book.rating)

    def test_filter_wrong_annotation(self):
        with self.assertRaisesMessage(
            FieldError, "Cannot resolve keyword 'nope' into field."
        ):
            list(
                Book.objects.annotate(sum_rating=Sum("rating")).filter(
                    sum_rating=F("nope")
                )
            )

    def test_decimal_annotation(self):
        salary = Decimal(10) ** -Employee._meta.get_field("salary").decimal_places
        Employee.objects.create(
            first_name="Max",
            last_name="Paine",
            store=Store.objects.first(),
            age=23,
            salary=salary,
        )
        self.assertEqual(
            Employee.objects.annotate(new_salary=F("salary") / 10).get().new_salary,
            salary / 10,
        )

    def test_filter_decimal_annotation(self):
        qs = (
            Book.objects.annotate(new_price=F("price") + 1)
            .filter(new_price=Decimal(31))
            .values_list("new_price")
        )
        self.assertEqual(qs.get(), (Decimal(31),))

    def test_combined_annotation_commutative(self):
        book1 = Book.objects.annotate(adjusted_rating=F("rating") + 2).get(
            pk=self.b1.pk
        )
        book2 = Book.objects.annotate(adjusted_rating=2 + F("rating")).get(
            pk=self.b1.pk
        )
        self.assertEqual(book1.adjusted_rating, book2.adjusted_rating)
        book1 = Book.objects.annotate(adjusted_rating=F("rating") + None).get(
            pk=self.b1.pk
        )
        book2 = Book.objects.annotate(adjusted_rating=None + F("rating")).get(
            pk=self.b1.pk
        )
        self.assertIs(book1.adjusted_rating, None)
        self.assertEqual(book1.adjusted_rating, book2.adjusted_rating)

    def test_update_with_annotation(self):
        book_preupdate = Book.objects.get(pk=self.b2.pk)
        Book.objects.annotate(other_rating=F("rating") - 1).update(
            rating=F("other_rating")
        )
        book_postupdate = Book.objects.get(pk=self.b2.pk)
        self.assertEqual(book_preupdate.rating - 1, book_postupdate.rating)

    def test_annotation_with_m2m(self):
        books = (
            Book.objects.annotate(author_age=F("authors__age"))
            .filter(pk=self.b1.pk)
            .order_by("author_age")
        )
        self.assertEqual(books[0].author_age, 34)
        self.assertEqual(books[1].author_age, 35)

    def test_annotation_reverse_m2m(self):
        books = (
            Book.objects.annotate(
                store_name=F("store__name"),
            )
            .filter(
                name="Practical Django Projects",
            )
            .order_by("store_name")
        )

        self.assertQuerySetEqual(
            books,
            ["Amazon.com", "Books.com", "Mamma and Pappa's Books"],
            lambda b: b.store_name,
        )

    def test_values_annotation(self):
        """
        Annotations can reference fields in a values clause,
        and contribute to an existing values clause.
        """
        # annotate references a field in values()
        qs = Book.objects.values("rating").annotate(other_rating=F("rating") - 1)
        book = qs.get(pk=self.b1.pk)
        self.assertEqual(book["rating"] - 1, book["other_rating"])

        # filter refs the annotated value
        book = qs.get(other_rating=4)
        self.assertEqual(book["other_rating"], 4)

        # can annotate an existing values with a new field
        book = qs.annotate(other_isbn=F("isbn")).get(other_rating=4)
        self.assertEqual(book["other_rating"], 4)
        self.assertEqual(book["other_isbn"], "155860191")

    def test_values_with_pk_annotation(self):
        # annotate references a field in values() with pk
        publishers = Publisher.objects.values("id", "book__rating").annotate(
            total=Sum("book__rating")
        )
        for publisher in publishers.filter(pk=self.p1.pk):
            self.assertEqual(publisher["book__rating"], publisher["total"])

    def test_defer_annotation(self):
        """
        Deferred attributes can be referenced by an annotation,
        but they are not themselves deferred, and cannot be deferred.
        """
        qs = Book.objects.defer("rating").annotate(other_rating=F("rating") - 1)

        with self.assertNumQueries(2):
            book = qs.get(other_rating=4)
            self.assertEqual(book.rating, 5)
            self.assertEqual(book.other_rating, 4)

        with self.assertRaisesMessage(
            FieldDoesNotExist, "Book has no field named 'other_rating'"
        ):
            book = qs.defer("other_rating").get(other_rating=4)

    def test_mti_annotations(self):
        """
        Fields on an inherited model can be referenced by an
        annotated field.
        """
        d = DepartmentStore.objects.create(
            name="Angus & Robinson",
            original_opening=datetime.date(2014, 3, 8),
            friday_night_closing=datetime.time(21, 00, 00),
            chain="Westfield",
        )

        books = Book.objects.filter(rating__gt=4)
        for b in books:
            d.books.add(b)

        qs = (
            DepartmentStore.objects.annotate(
                other_name=F("name"),
                other_chain=F("chain"),
                is_open=Value(True, BooleanField()),
                book_isbn=F("books__isbn"),
            )
            .order_by("book_isbn")
            .filter(chain="Westfield")
        )

        self.assertQuerySetEqual(
            qs,
            [
                ("Angus & Robinson", "Westfield", True, "155860191"),
                ("Angus & Robinson", "Westfield", True, "159059725"),
            ],
            lambda d: (d.other_name, d.other_chain, d.is_open, d.book_isbn),
        )

    def test_null_annotation(self):
        """
        Annotating None onto a model round-trips
        """
        book = Book.objects.annotate(
            no_value=Value(None, output_field=IntegerField())
        ).first()
        self.assertIsNone(book.no_value)

    def test_order_by_annotation(self):
        authors = Author.objects.annotate(other_age=F("age")).order_by("other_age")
        self.assertQuerySetEqual(
            authors,
            [
                25,
                29,
                29,
                34,
                35,
                37,
                45,
                46,
                57,
            ],
            lambda a: a.other_age,
        )

    def test_order_by_aggregate(self):
        authors = (
            Author.objects.values("age")
            .annotate(age_count=Count("age"))
            .order_by("age_count", "age")
        )
        self.assertQuerySetEqual(
            authors,
            [
                (25, 1),
                (34, 1),
                (35, 1),
                (37, 1),
                (45, 1),
                (46, 1),
                (57, 1),
                (29, 2),
            ],
            lambda a: (a["age"], a["age_count"]),
        )

    def test_raw_sql_with_inherited_field(self):
        DepartmentStore.objects.create(
            name="Angus & Robinson",
            original_opening=datetime.date(2014, 3, 8),
            friday_night_closing=datetime.time(21),
            chain="Westfield",
            area=123,
        )
        tests = (
            ("name", "Angus & Robinson"),
            ("surface", 123),
            ("case when name='Angus & Robinson' then chain else name end", "Westfield"),
        )
        for sql, expected_result in tests:
            with self.subTest(sql=sql):
                self.assertSequenceEqual(
                    DepartmentStore.objects.annotate(
                        annotation=RawSQL(sql, ()),
                    ).values_list("annotation", flat=True),
                    [expected_result],
                )

    def test_annotate_exists(self):
        authors = Author.objects.annotate(c=Count("id")).filter(c__gt=1)
        self.assertFalse(authors.exists())

    def test_column_field_ordering(self):
        """
        Columns are aligned in the correct order for resolve_columns. This test
        will fail on MySQL if column ordering is out. Column fields should be
        aligned as:
        1. extra_select
        2. model_fields
        3. annotation_fields
        4. model_related_fields
        """
        store = Store.objects.first()
        Employee.objects.create(
            id=1,
            first_name="Max",
            manager=True,
            last_name="Paine",
            store=store,
            age=23,
            salary=Decimal(50000.00),
        )
        Employee.objects.create(
            id=2,
            first_name="Buffy",
            manager=False,
            last_name="Summers",
            store=store,
            age=18,
            salary=Decimal(40000.00),
        )

        qs = (
            Employee.objects.extra(select={"random_value": "42"})
            .select_related("store")
            .annotate(
                annotated_value=Value(17),
            )
        )

        rows = [
            (1, "Max", True, 42, "Paine", 23, Decimal(50000.00), store.name, 17),
            (2, "Buffy", False, 42, "Summers", 18, Decimal(40000.00), store.name, 17),
        ]

        self.assertQuerySetEqual(
            qs.order_by("id"),
            rows,
            lambda e: (
                e.id,
                e.first_name,
                e.manager,
                e.random_value,
                e.last_name,
                e.age,
                e.salary,
                e.store.name,
                e.annotated_value,
            ),
        )

    def test_column_field_ordering_with_deferred(self):
        store = Store.objects.first()
        Employee.objects.create(
            id=1,
            first_name="Max",
            manager=True,
            last_name="Paine",
            store=store,
            age=23,
            salary=Decimal(50000.00),
        )
        Employee.objects.create(
            id=2,
            first_name="Buffy",
            manager=False,
            last_name="Summers",
            store=store,
            age=18,
            salary=Decimal(40000.00),
        )

        qs = (
            Employee.objects.extra(select={"random_value": "42"})
            .select_related("store")
            .annotate(
                annotated_value=Value(17),
            )
        )

        rows = [
            (1, "Max", True, 42, "Paine", 23, Decimal(50000.00), store.name, 17),
            (2, "Buffy", False, 42, "Summers", 18, Decimal(40000.00), store.name, 17),
        ]

        # and we respect deferred columns!
        self.assertQuerySetEqual(
            qs.defer("age").order_by("id"),
            rows,
            lambda e: (
                e.id,
                e.first_name,
                e.manager,
                e.random_value,
                e.last_name,
                e.age,
                e.salary,
                e.store.name,
                e.annotated_value,
            ),
        )

    def test_custom_functions(self):
        Company(
            name="Apple",
            motto=None,
            ticker_name="APPL",
            description="Beautiful Devices",
        ).save()
        Company(
            name="Django Software Foundation",
            motto=None,
            ticker_name=None,
            description=None,
        ).save()
        Company(
            name="Google",
            motto="Do No Evil",
            ticker_name="GOOG",
            description="Internet Company",
        ).save()
        Company(
            name="Yahoo", motto=None, ticker_name=None, description="Internet Company"
        ).save()

        qs = Company.objects.annotate(
            tagline=Func(
                F("motto"),
                F("ticker_name"),
                F("description"),
                Value("No Tag"),
                function="COALESCE",
            )
        ).order_by("name")

        self.assertQuerySetEqual(
            qs,
            [
                ("Apple", "APPL"),
                ("Django Software Foundation", "No Tag"),
                ("Google", "Do No Evil"),
                ("Yahoo", "Internet Company"),
            ],
            lambda c: (c.name, c.tagline),
        )

    def test_custom_functions_can_ref_other_functions(self):
        Company(
            name="Apple",
            motto=None,
            ticker_name="APPL",
            description="Beautiful Devices",
        ).save()
        Company(
            name="Django Software Foundation",
            motto=None,
            ticker_name=None,
            description=None,
        ).save()
        Company(
            name="Google",
            motto="Do No Evil",
            ticker_name="GOOG",
            description="Internet Company",
        ).save()
        Company(
            name="Yahoo", motto=None, ticker_name=None, description="Internet Company"
        ).save()

        class Lower(Func):
            function = "LOWER"

        qs = (
            Company.objects.annotate(
                tagline=Func(
                    F("motto"),
                    F("ticker_name"),
                    F("description"),
                    Value("No Tag"),
                    function="COALESCE",
                )
            )
            .annotate(
                tagline_lower=Lower(F("tagline")),
            )
            .order_by("name")
        )

        # LOWER function supported by:
        # oracle, postgres, mysql, sqlite, sqlserver

        self.assertQuerySetEqual(
            qs,
            [
                ("Apple", "APPL".lower()),
                ("Django Software Foundation", "No Tag".lower()),
                ("Google", "Do No Evil".lower()),
                ("Yahoo", "Internet Company".lower()),
            ],
            lambda c: (c.name, c.tagline_lower),
        )

    def test_boolean_value_annotation(self):
        books = Book.objects.annotate(
            is_book=Value(True, output_field=BooleanField()),
            is_pony=Value(False, output_field=BooleanField()),
            is_none=Value(None, output_field=BooleanField(null=True)),
        )
        self.assertGreater(len(books), 0)
        for book in books:
            self.assertIs(book.is_book, True)
            self.assertIs(book.is_pony, False)
            self.assertIsNone(book.is_none)

    def test_annotation_in_f_grouped_by_annotation(self):
        qs = (
            Publisher.objects.annotate(multiplier=Value(3))
            # group by option => sum of value * multiplier
            .values("name")
            .annotate(multiplied_value_sum=Sum(F("multiplier") * F("num_awards")))
            .order_by()
        )
        self.assertCountEqual(
            qs,
            [
                {"multiplied_value_sum": 9, "name": "Apress"},
                {"multiplied_value_sum": 0, "name": "Jonno's House of Books"},
                {"multiplied_value_sum": 27, "name": "Morgan Kaufmann"},
                {"multiplied_value_sum": 21, "name": "Prentice Hall"},
                {"multiplied_value_sum": 3, "name": "Sams"},
            ],
        )

    def test_arguments_must_be_expressions(self):
        msg = "QuerySet.annotate() received non-expression(s): %s."
        with self.assertRaisesMessage(TypeError, msg % BooleanField()):
            Book.objects.annotate(BooleanField())
        with self.assertRaisesMessage(TypeError, msg % True):
            Book.objects.annotate(is_book=True)
        with self.assertRaisesMessage(
            TypeError, msg % ", ".join([str(BooleanField()), "True"])
        ):
            Book.objects.annotate(BooleanField(), Value(False), is_book=True)

    def test_chaining_annotation_filter_with_m2m(self):
        qs = (
            Author.objects.filter(
                name="Adrian Holovaty",
                friends__age=35,
            )
            .annotate(
                jacob_name=F("friends__name"),
            )
            .filter(
                friends__age=29,
            )
            .annotate(
                james_name=F("friends__name"),
            )
            .values("jacob_name", "james_name")
        )
        self.assertCountEqual(
            qs,
            [{"jacob_name": "Jacob Kaplan-Moss", "james_name": "James Bennett"}],
        )

    def test_annotation_filter_with_subquery(self):
        long_books_qs = (
            Book.objects.filter(
                publisher=OuterRef("pk"),
                pages__gt=400,
            )
            .values("publisher")
            .annotate(count=Count("pk"))
            .values("count")
        )
        publisher_books_qs = (
            Publisher.objects.annotate(
                total_books=Count("book"),
            )
            .filter(
                total_books=Subquery(long_books_qs, output_field=IntegerField()),
            )
            .values("name")
        )
        self.assertCountEqual(
            publisher_books_qs, [{"name": "Sams"}, {"name": "Morgan Kaufmann"}]
        )

    def test_annotation_and_alias_filter_in_subquery(self):
        awarded_publishers_qs = (
            Publisher.objects.filter(num_awards__gt=4)
            .annotate(publisher_annotate=Value(1))
            .alias(publisher_alias=Value(1))
        )
        qs = Publisher.objects.filter(pk__in=awarded_publishers_qs)
        self.assertCountEqual(qs, [self.p3, self.p4])

    def test_annotation_and_alias_filter_related_in_subquery(self):
        long_books_qs = (
            Book.objects.filter(pages__gt=400)
            .annotate(book_annotate=Value(1))
            .alias(book_alias=Value(1))
        )
        publisher_books_qs = Publisher.objects.filter(
            book__in=long_books_qs,
        ).values("name")
        self.assertCountEqual(
            publisher_books_qs,
            [
                {"name": "Apress"},
                {"name": "Sams"},
                {"name": "Prentice Hall"},
                {"name": "Morgan Kaufmann"},
            ],
        )

    def test_annotation_exists_none_query(self):
        self.assertIs(
            Author.objects.annotate(exists=Exists(Company.objects.none()))
            .get(pk=self.a1.pk)
            .exists,
            False,
        )

    def test_annotation_exists_aggregate_values_chaining(self):
        qs = (
            Book.objects.values("publisher")
            .annotate(
                has_authors=Exists(
                    Book.authors.through.objects.filter(book=OuterRef("pk"))
                ),
                max_pubdate=Max("pubdate"),
            )
            .values_list("max_pubdate", flat=True)
            .order_by("max_pubdate")
        )
        self.assertCountEqual(
            qs,
            [
                datetime.date(1991, 10, 15),
                datetime.date(2008, 3, 3),
                datetime.date(2008, 6, 23),
                datetime.date(2008, 11, 3),
            ],
        )

    @skipUnlessDBFeature("supports_subqueries_in_group_by")
    def test_annotation_subquery_and_aggregate_values_chaining(self):
        qs = (
            Book.objects.annotate(pub_year=ExtractYear("pubdate"))
            .values("pub_year")
            .annotate(
                top_rating=Subquery(
                    Book.objects.filter(pubdate__year=OuterRef("pub_year"))
                    .order_by("-rating")
                    .values("rating")[:1]
                ),
                total_pages=Sum("pages"),
            )
            .values("pub_year", "total_pages", "top_rating")
        )
        self.assertCountEqual(
            qs,
            [
                {"pub_year": 1991, "top_rating": 5.0, "total_pages": 946},
                {"pub_year": 1995, "top_rating": 4.0, "total_pages": 1132},
                {"pub_year": 2007, "top_rating": 4.5, "total_pages": 447},
                {"pub_year": 2008, "top_rating": 4.0, "total_pages": 1178},
            ],
        )

    def test_annotation_subquery_outerref_transform(self):
        qs = Book.objects.annotate(
            top_rating_year=Subquery(
                Book.objects.filter(pubdate__year=OuterRef("pubdate__year"))
                .order_by("-rating")
                .values("rating")[:1]
            ),
        ).values("pubdate__year", "top_rating_year")
        self.assertCountEqual(
            qs,
            [
                {"pubdate__year": 1991, "top_rating_year": 5.0},
                {"pubdate__year": 1995, "top_rating_year": 4.0},
                {"pubdate__year": 2007, "top_rating_year": 4.5},
                {"pubdate__year": 2008, "top_rating_year": 4.0},
                {"pubdate__year": 2008, "top_rating_year": 4.0},
                {"pubdate__year": 2008, "top_rating_year": 4.0},
            ],
        )

    def test_annotation_aggregate_with_m2o(self):
        qs = (
            Author.objects.filter(age__lt=30)
            .annotate(
                max_pages=Case(
                    When(book_contact_set__isnull=True, then=Value(0)),
                    default=Max(F("book__pages")),
                ),
            )
            .values("name", "max_pages")
        )
        self.assertCountEqual(
            qs,
            [
                {"name": "James Bennett", "max_pages": 300},
                {"name": "Paul Bissex", "max_pages": 0},
                {"name": "Wesley J. Chun", "max_pages": 0},
            ],
        )

    def test_alias_sql_injection(self):
        crafted_alias = """injected_name" from "annotations_book"; --"""
        msg = (
            "Column aliases cannot contain whitespace characters, quotation marks, "
            "semicolons, or SQL comments."
        )
        with self.assertRaisesMessage(ValueError, msg):
            Book.objects.annotate(**{crafted_alias: Value(1)})

    def test_alias_forbidden_chars(self):
        tests = [
            'al"ias',
            "a'lias",
            "ali`as",
            "alia s",
            "alias\t",
            "ali\nas",
            "alias--",
            "ali/*as",
            "alias*/",
            "alias;",
            # [] are used by MSSQL.
            "alias[",
            "alias]",
        ]
        msg = (
            "Column aliases cannot contain whitespace characters, quotation marks, "
            "semicolons, or SQL comments."
        )
        for crafted_alias in tests:
            with self.subTest(crafted_alias):
                with self.assertRaisesMessage(ValueError, msg):
                    Book.objects.annotate(**{crafted_alias: Value(1)})


class AliasTests(TestCase):
    @classmethod
    def setUpTestData(cls):
        cls.a1 = Author.objects.create(name="Adrian Holovaty", age=34)
        cls.a2 = Author.objects.create(name="Jacob Kaplan-Moss", age=35)
        cls.a3 = Author.objects.create(name="James Bennett", age=34)
        cls.a4 = Author.objects.create(name="Peter Norvig", age=57)
        cls.a5 = Author.objects.create(name="Stuart Russell", age=46)
        p1 = Publisher.objects.create(name="Apress", num_awards=3)

        cls.b1 = Book.objects.create(
            isbn="159059725",
            pages=447,
            rating=4.5,
            price=Decimal("30.00"),
            contact=cls.a1,
            publisher=p1,
            pubdate=datetime.date(2007, 12, 6),
            name="The Definitive Guide to Django: Web Development Done Right",
        )
        cls.b2 = Book.objects.create(
            isbn="159059996",
            pages=300,
            rating=4.0,
            price=Decimal("29.69"),
            contact=cls.a3,
            publisher=p1,
            pubdate=datetime.date(2008, 6, 23),
            name="Practical Django Projects",
        )
        cls.b3 = Book.objects.create(
            isbn="013790395",
            pages=1132,
            rating=4.0,
            price=Decimal("82.80"),
            contact=cls.a4,
            publisher=p1,
            pubdate=datetime.date(1995, 1, 15),
            name="Artificial Intelligence: A Modern Approach",
        )
        cls.b4 = Book.objects.create(
            isbn="155860191",
            pages=946,
            rating=5.0,
            price=Decimal("75.00"),
            contact=cls.a4,
            publisher=p1,
            pubdate=datetime.date(1991, 10, 15),
            name=(
                "Paradigms of Artificial Intelligence Programming: Case Studies in "
                "Common Lisp"
            ),
        )
        cls.b1.authors.add(cls.a1, cls.a2)
        cls.b2.authors.add(cls.a3)
        cls.b3.authors.add(cls.a4, cls.a5)
        cls.b4.authors.add(cls.a4)

        Store.objects.create(
            name="Amazon.com",
            original_opening=datetime.datetime(1994, 4, 23, 9, 17, 42),
            friday_night_closing=datetime.time(23, 59, 59),
        )
        Store.objects.create(
            name="Books.com",
            original_opening=datetime.datetime(2001, 3, 15, 11, 23, 37),
            friday_night_closing=datetime.time(23, 59, 59),
        )

    def test_basic_alias(self):
        qs = Book.objects.alias(is_book=Value(1))
        self.assertIs(hasattr(qs.first(), "is_book"), False)

    def test_basic_alias_annotation(self):
        qs = Book.objects.alias(
            is_book_alias=Value(1),
        ).annotate(is_book=F("is_book_alias"))
        self.assertIs(hasattr(qs.first(), "is_book_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.is_book, 1)

    def test_basic_alias_f_annotation(self):
        qs = Book.objects.alias(another_rating_alias=F("rating")).annotate(
            another_rating=F("another_rating_alias")
        )
        self.assertIs(hasattr(qs.first(), "another_rating_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.another_rating, book.rating)

    def test_basic_alias_f_transform_annotation(self):
        qs = Book.objects.alias(
            pubdate_alias=F("pubdate"),
        ).annotate(pubdate_year=F("pubdate_alias__year"))
        self.assertIs(hasattr(qs.first(), "pubdate_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.pubdate_year, book.pubdate.year)

    def test_alias_after_annotation(self):
        qs = Book.objects.annotate(
            is_book=Value(1),
        ).alias(is_book_alias=F("is_book"))
        book = qs.first()
        self.assertIs(hasattr(book, "is_book"), True)
        self.assertIs(hasattr(book, "is_book_alias"), False)

    def test_overwrite_annotation_with_alias(self):
        qs = Book.objects.annotate(is_book=Value(1)).alias(is_book=F("is_book"))
        self.assertIs(hasattr(qs.first(), "is_book"), False)

    def test_overwrite_alias_with_annotation(self):
        qs = Book.objects.alias(is_book=Value(1)).annotate(is_book=F("is_book"))
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.is_book, 1)

    def test_alias_annotation_expression(self):
        qs = Book.objects.alias(
            is_book_alias=Value(1),
        ).annotate(is_book=Coalesce("is_book_alias", 0))
        self.assertIs(hasattr(qs.first(), "is_book_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.is_book, 1)

    def test_alias_default_alias_expression(self):
        qs = Author.objects.alias(
            Sum("book__pages"),
        ).filter(book__pages__sum__gt=2000)
        self.assertIs(hasattr(qs.first(), "book__pages__sum"), False)
        self.assertSequenceEqual(qs, [self.a4])

    def test_joined_alias_annotation(self):
        qs = (
            Book.objects.select_related("publisher")
            .alias(
                num_awards_alias=F("publisher__num_awards"),
            )
            .annotate(num_awards=F("num_awards_alias"))
        )
        self.assertIs(hasattr(qs.first(), "num_awards_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.num_awards, book.publisher.num_awards)

    def test_alias_annotate_with_aggregation(self):
        qs = Book.objects.alias(
            is_book_alias=Value(1),
            rating_count_alias=Count("rating"),
        ).annotate(
            is_book=F("is_book_alias"),
            rating_count=F("rating_count_alias"),
        )
        book = qs.first()
        self.assertIs(hasattr(book, "is_book_alias"), False)
        self.assertIs(hasattr(book, "rating_count_alias"), False)
        for book in qs:
            with self.subTest(book=book):
                self.assertEqual(book.is_book, 1)
                self.assertEqual(book.rating_count, 1)

    def test_filter_alias_with_f(self):
        qs = Book.objects.alias(
            other_rating=F("rating"),
        ).filter(other_rating=4.5)
        self.assertIs(hasattr(qs.first(), "other_rating"), False)
        self.assertSequenceEqual(qs, [self.b1])

    def test_filter_alias_with_double_f(self):
        qs = Book.objects.alias(
            other_rating=F("rating"),
        ).filter(other_rating=F("rating"))
        self.assertIs(hasattr(qs.first(), "other_rating"), False)
        self.assertEqual(qs.count(), Book.objects.count())

    def test_filter_alias_agg_with_double_f(self):
        qs = Book.objects.alias(
            sum_rating=Sum("rating"),
        ).filter(sum_rating=F("sum_rating"))
        self.assertIs(hasattr(qs.first(), "sum_rating"), False)
        self.assertEqual(qs.count(), Book.objects.count())

    def test_update_with_alias(self):
        Book.objects.alias(
            other_rating=F("rating") - 1,
        ).update(rating=F("other_rating"))
        self.b1.refresh_from_db()
        self.assertEqual(self.b1.rating, 3.5)

    def test_order_by_alias(self):
        qs = Author.objects.alias(other_age=F("age")).order_by("other_age")
        self.assertIs(hasattr(qs.first(), "other_age"), False)
        self.assertQuerySetEqual(qs, [34, 34, 35, 46, 57], lambda a: a.age)

    def test_order_by_alias_aggregate(self):
        qs = (
            Author.objects.values("age")
            .alias(age_count=Count("age"))
            .order_by("age_count", "age")
        )
        self.assertIs(hasattr(qs.first(), "age_count"), False)
        self.assertQuerySetEqual(qs, [35, 46, 57, 34], lambda a: a["age"])

    def test_dates_alias(self):
        qs = Book.objects.alias(
            pubdate_alias=F("pubdate"),
        ).dates("pubdate_alias", "month")
        self.assertCountEqual(
            qs,
            [
                datetime.date(1991, 10, 1),
                datetime.date(1995, 1, 1),
                datetime.date(2007, 12, 1),
                datetime.date(2008, 6, 1),
            ],
        )

    def test_datetimes_alias(self):
        qs = Store.objects.alias(
            original_opening_alias=F("original_opening"),
        ).datetimes("original_opening_alias", "year")
        self.assertCountEqual(
            qs,
            [
                datetime.datetime(1994, 1, 1),
                datetime.datetime(2001, 1, 1),
            ],
        )

    def test_aggregate_alias(self):
        msg = (
            "Cannot aggregate over the 'other_age' alias. Use annotate() to promote it."
        )
        with self.assertRaisesMessage(FieldError, msg):
            Author.objects.alias(
                other_age=F("age"),
            ).aggregate(otherage_sum=Sum("other_age"))

    def test_defer_only_alias(self):
        qs = Book.objects.alias(rating_alias=F("rating") - 1)
        msg = "Book has no field named 'rating_alias'"
        for operation in ["defer", "only"]:
            with self.subTest(operation=operation):
                with self.assertRaisesMessage(FieldDoesNotExist, msg):
                    getattr(qs, operation)("rating_alias").first()

    @skipUnlessDBFeature("can_distinct_on_fields")
    def test_distinct_on_alias(self):
        qs = Book.objects.alias(rating_alias=F("rating") - 1)
        msg = "Cannot resolve keyword 'rating_alias' into field."
        with self.assertRaisesMessage(FieldError, msg):
            qs.distinct("rating_alias").first()

    def test_values_alias(self):
        qs = Book.objects.alias(rating_alias=F("rating") - 1)
        msg = "Cannot select the 'rating_alias' alias. Use annotate() to promote it."
        for operation in ["values", "values_list"]:
            with self.subTest(operation=operation):
                with self.assertRaisesMessage(FieldError, msg):
                    getattr(qs, operation)("rating_alias")

    def test_alias_sql_injection(self):
        crafted_alias = """injected_name" from "annotations_book"; --"""
        msg = (
            "Column aliases cannot contain whitespace characters, quotation marks, "
            "semicolons, or SQL comments."
        )
        with self.assertRaisesMessage(ValueError, msg):
            Book.objects.alias(**{crafted_alias: Value(1)})