make first() an Optional, allow to specify QuerySet with one parameter (#136)

2025-12-06 20:24:31 +08:00 · 2019-08-23 03:31:07 +03:00
parent ff7bf33e9c
commit 656105bab2
9 changed files with 190 additions and 164 deletions
--- a/django-stubs/db/models/manager.pyi
+++ b/django-stubs/db/models/manager.pyi
@@ -5,7 +5,7 @@ from django.db.models.query import QuerySet

 _T = TypeVar("_T", bound=Model, covariant=True)

-class BaseManager(QuerySet[_T, _T]):
+class BaseManager(QuerySet[_T]):
    creation_counter: int = ...
    auto_created: bool = ...
    use_in_migrations: bool = ...
@@ -21,7 +21,7 @@ class BaseManager(QuerySet[_T, _T]):
    def _get_queryset_methods(cls, queryset_class: type) -> Dict[str, Any]: ...
    def contribute_to_class(self, model: Type[Model], name: str) -> None: ...
    def db_manager(self, using: Optional[str] = ..., hints: Optional[Dict[str, Model]] = ...) -> Manager: ...
-    def get_queryset(self) -> QuerySet[_T, _T]: ...
+    def get_queryset(self) -> QuerySet[_T]: ...

 class Manager(BaseManager[_T]): ...

--- a/django-stubs/db/models/query.pyi
+++ b/django-stubs/db/models/query.pyi
@@ -27,6 +27,111 @@ from django.db import models
 from django.db.models import Manager
 from django.db.models.query_utils import Q as Q

+_T = TypeVar("_T", bound=models.Model, covariant=True)
+_QS = TypeVar("_QS", bound="QuerySet")
+
+class QuerySet(Generic[_T], Collection[_T], Sized):
+    query: Query
+    def __init__(
+        self,
+        model: Optional[Type[models.Model]] = ...,
+        query: Optional[Query] = ...,
+        using: Optional[str] = ...,
+        hints: Optional[Dict[str, models.Model]] = ...,
+    ) -> None: ...
+    @classmethod
+    def as_manager(cls) -> Manager[Any]: ...
+    def __len__(self) -> int: ...
+    def __iter__(self) -> Iterator[_T]: ...
+    def __contains__(self, x: object) -> bool: ...
+    @overload
+    def __getitem__(self, i: int) -> _T: ...
+    @overload
+    def __getitem__(self, s: slice) -> QuerySet[_T]: ...
+    def __bool__(self) -> bool: ...
+    def __class_getitem__(cls, item: Type[_T]):
+        pass
+    def __getstate__(self) -> Dict[str, Any]: ...
+    # __and__ and __or__ ignore the other QuerySet's _Row type parameter
+    # because they use the same row type as the self QuerySet.
+    # Technically, the other QuerySet must be of the same type _T, but _T is covariant
+    def __and__(self, other: QuerySet[_T]) -> QuerySet[_T]: ...
+    def __or__(self, other: QuerySet[_T]) -> QuerySet[_T]: ...
+    def iterator(self, chunk_size: int = ...) -> Iterator[_T]: ...
+    def aggregate(self, *args: Any, **kwargs: Any) -> Dict[str, Any]: ...
+    def get(self, *args: Any, **kwargs: Any) -> _T: ...
+    def create(self, *args: Any, **kwargs: Any) -> _T: ...
+    def bulk_create(
+        self, objs: Iterable[Model], batch_size: Optional[int] = ..., ignore_conflicts: bool = ...
+    ) -> List[_T]: ...
+    def get_or_create(self, defaults: Optional[MutableMapping[str, Any]] = ..., **kwargs: Any) -> Tuple[_T, bool]: ...
+    def update_or_create(
+        self, defaults: Optional[MutableMapping[str, Any]] = ..., **kwargs: Any
+    ) -> Tuple[_T, bool]: ...
+    def earliest(self, *fields: Any, field_name: Optional[Any] = ...) -> _T: ...
+    def latest(self, *fields: Any, field_name: Optional[Any] = ...) -> _T: ...
+    def first(self) -> Optional[_T]: ...
+    def last(self) -> Optional[_T]: ...
+    def in_bulk(self, id_list: Iterable[Any] = ..., *, field_name: str = ...) -> Dict[Any, _T]: ...
+    def delete(self) -> Tuple[int, Dict[str, int]]: ...
+    def update(self, **kwargs: Any) -> int: ...
+    def exists(self) -> bool: ...
+    def explain(self, *, format: Optional[Any] = ..., **options: Any) -> str: ...
+    def raw(
+        self,
+        raw_query: str,
+        params: Any = ...,
+        translations: Optional[Dict[str, str]] = ...,
+        using: Optional[str] = ...,
+    ) -> RawQuerySet: ...
+    # The type of values may be overridden to be more specific in the mypy plugin, depending on the fields param
+    def values(self, *fields: Union[str, Combinable], **expressions: Any) -> ValuesQuerySet[_T, Dict[str, Any]]: ...
+    # The type of values_list may be overridden to be more specific in the mypy plugin, depending on the fields param
+    def values_list(
+        self, *fields: Union[str, Combinable], flat: bool = ..., named: bool = ...
+    ) -> ValuesQuerySet[_T, Any]: ...
+    def dates(self, field_name: str, kind: str, order: str = ...) -> ValuesQuerySet[_T, datetime.date]: ...
+    def datetimes(
+        self, field_name: str, kind: str, order: str = ..., tzinfo: None = ...
+    ) -> ValuesQuerySet[_T, datetime.datetime]: ...
+    def none(self) -> QuerySet[_T]: ...
+    def all(self) -> QuerySet[_T]: ...
+    def filter(self, *args: Any, **kwargs: Any) -> QuerySet[_T]: ...
+    def exclude(self, *args: Any, **kwargs: Any) -> QuerySet[_T]: ...
+    def complex_filter(self, filter_obj: Any) -> QuerySet[_T]: ...
+    def count(self) -> int: ...
+    def union(self, *other_qs: Any, all: bool = ...) -> QuerySet[_T]: ...
+    def intersection(self, *other_qs: Any) -> QuerySet[_T]: ...
+    def difference(self, *other_qs: Any) -> QuerySet[_T]: ...
+    def select_for_update(self, nowait: bool = ..., skip_locked: bool = ..., of: Tuple = ...) -> QuerySet[_T]: ...
+    def select_related(self, *fields: Any) -> QuerySet[_T]: ...
+    def prefetch_related(self, *lookups: Any) -> QuerySet[_T]: ...
+    # TODO: return type
+    def annotate(self, *args: Any, **kwargs: Any) -> QuerySet[Any]: ...
+    def order_by(self, *field_names: Any) -> QuerySet[_T]: ...
+    def distinct(self, *field_names: Any) -> QuerySet[_T]: ...
+    # extra() return type won't be supported any time soon
+    def extra(
+        self,
+        select: Optional[Dict[str, Any]] = ...,
+        where: Optional[List[str]] = ...,
+        params: Optional[List[Any]] = ...,
+        tables: Optional[List[str]] = ...,
+        order_by: Optional[Sequence[str]] = ...,
+        select_params: Optional[Sequence[Any]] = ...,
+    ) -> QuerySet[Any]: ...
+    def reverse(self) -> QuerySet[_T]: ...
+    def defer(self, *fields: Any) -> QuerySet[_T]: ...
+    def only(self, *fields: Any) -> QuerySet[_T]: ...
+    def using(self, alias: Optional[str]) -> QuerySet[_T]: ...
+    @property
+    def ordered(self) -> bool: ...
+    @property
+    def db(self) -> str: ...
+    def resolve_expression(self, *args: Any, **kwargs: Any) -> Any: ...
+    # TODO: remove when django adds __class_getitem__ methods
+    def __getattr__(self, item: str) -> Any: ...
+
 _Row = TypeVar("_Row", covariant=True)

 class BaseIterable(Sequence[_Row]):
@@ -47,88 +152,39 @@ class NamedValuesListIterable(ValuesListIterable): ...
 class FlatValuesListIterable(BaseIterable):
    def __iter__(self) -> Iterator[Any]: ...

-_T = TypeVar("_T", bound=models.Model, covariant=True)
-
-class QuerySet(Generic[_T, _Row], Collection[_Row], Sized):
-    query: Query
-    def __init__(
-        self,
-        model: Optional[Type[models.Model]] = ...,
-        query: Optional[Query] = ...,
-        using: Optional[str] = ...,
-        hints: Optional[Dict[str, models.Model]] = ...,
-    ) -> None: ...
-    @classmethod
-    def as_manager(cls) -> Manager[Any]: ...
-    def __len__(self) -> int: ...
-    def __iter__(self) -> Iterator[_Row]: ...
-    def __contains__(self, x: object) -> bool: ...
-    @overload
+class ValuesQuerySet(Generic[_T, _Row], QuerySet[_T], Collection[_Row], Sized):
+    def __iter__(self) -> Iterator[_Row]: ...  # type: ignore
+    @overload  # type: ignore
    def __getitem__(self, i: int) -> _Row: ...
    @overload
-    def __getitem__(self, s: slice) -> QuerySet[_T, _Row]: ...
-    def __bool__(self) -> bool: ...
-    def __class_getitem__(cls, item: Type[_T]):
-        pass
-    def __getstate__(self) -> Dict[str, Any]: ...
-    # __and__ and __or__ ignore the other QuerySet's _Row type parameter because they use the same row type as the self QuerySet.
+    def __getitem__(self, s: slice) -> ValuesQuerySet[_T, _Row]: ...
    # Technically, the other QuerySet must be of the same type _T, but _T is covariant
-    def __and__(self, other: QuerySet[_T, Any]) -> QuerySet[_T, _Row]: ...
-    def __or__(self, other: QuerySet[_T, Any]) -> QuerySet[_T, _Row]: ...
-    def iterator(self, chunk_size: int = ...) -> Iterator[_Row]: ...
-    def aggregate(self, *args: Any, **kwargs: Any) -> Dict[str, Any]: ...
-    def get(self, *args: Any, **kwargs: Any) -> _Row: ...
-    def create(self, *args: Any, **kwargs: Any) -> _T: ...
-    def bulk_create(
-        self, objs: Iterable[Model], batch_size: Optional[int] = ..., ignore_conflicts: bool = ...
-    ) -> List[_T]: ...
-    def get_or_create(self, defaults: Optional[MutableMapping[str, Any]] = ..., **kwargs: Any) -> Tuple[_T, bool]: ...
-    def update_or_create(
-        self, defaults: Optional[MutableMapping[str, Any]] = ..., **kwargs: Any
-    ) -> Tuple[_T, bool]: ...
-    def earliest(self, *fields: Any, field_name: Optional[Any] = ...) -> _Row: ...
-    def latest(self, *fields: Any, field_name: Optional[Any] = ...) -> _Row: ...
-    # technically it's Optional[_Row], but it creates a lot of false-positives (same for last())
-    def first(self) -> _Row: ...
-    def last(self) -> _Row: ...
-    def in_bulk(self, id_list: Iterable[Any] = ..., *, field_name: str = ...) -> Dict[Any, _T]: ...
-    def delete(self) -> Tuple[int, Dict[str, int]]: ...
-    def update(self, **kwargs: Any) -> int: ...
-    def exists(self) -> bool: ...
-    def explain(self, *, format: Optional[Any] = ..., **options: Any) -> str: ...
-    def raw(
-        self,
-        raw_query: str,
-        params: Any = ...,
-        translations: Optional[Dict[str, str]] = ...,
-        using: Optional[str] = ...,
-    ) -> RawQuerySet: ...
-    # The type of values may be overridden to be more specific in the mypy plugin, depending on the fields param
-    def values(self, *fields: Union[str, Combinable], **expressions: Any) -> QuerySet[_T, Dict[str, Any]]: ...
-    # The type of values_list may be overridden to be more specific in the mypy plugin, depending on the fields param
-    def values_list(
-        self, *fields: Union[str, Combinable], flat: bool = ..., named: bool = ...
-    ) -> QuerySet[_T, Any]: ...
-    def dates(self, field_name: str, kind: str, order: str = ...) -> QuerySet[_T, datetime.date]: ...
-    def datetimes(
-        self, field_name: str, kind: str, order: str = ..., tzinfo: None = ...
-    ) -> QuerySet[_T, datetime.datetime]: ...
-    def none(self) -> QuerySet[_T, _Row]: ...
-    def all(self) -> QuerySet[_T, _Row]: ...
-    def filter(self, *args: Any, **kwargs: Any) -> QuerySet[_T, _Row]: ...
-    def exclude(self, *args: Any, **kwargs: Any) -> QuerySet[_T, _Row]: ...
-    def complex_filter(self, filter_obj: Any) -> QuerySet[_T, _Row]: ...
+    def __and__(self, other: ValuesQuerySet[_T, _Row]) -> ValuesQuerySet[_T, _Row]: ...  # type: ignore
+    def __or__(self, other: ValuesQuerySet[_T, _Row]) -> ValuesQuerySet[_T, _Row]: ...  # type: ignore
+    def iterator(self, chunk_size: int = ...) -> Iterator[_Row]: ...  # type: ignore
+    def get(self, *args: Any, **kwargs: Any) -> _Row: ...  # type: ignore
+    def earliest(self, *fields: Any, field_name: Optional[Any] = ...) -> _Row: ...  # type: ignore
+    def latest(self, *fields: Any, field_name: Optional[Any] = ...) -> _Row: ...  # type: ignore
+    def first(self) -> Optional[_Row]: ...  # type: ignore
+    def last(self) -> Optional[_Row]: ...  # type: ignore
+    def none(self) -> ValuesQuerySet[_T, _Row]: ...
+    def all(self) -> ValuesQuerySet[_T, _Row]: ...
+    def filter(self, *args: Any, **kwargs: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def exclude(self, *args: Any, **kwargs: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def complex_filter(self, filter_obj: Any) -> ValuesQuerySet[_T, _Row]: ...
    def count(self) -> int: ...
-    def union(self, *other_qs: Any, all: bool = ...) -> QuerySet[_T, _Row]: ...
-    def intersection(self, *other_qs: Any) -> QuerySet[_T, _Row]: ...
-    def difference(self, *other_qs: Any) -> QuerySet[_T, _Row]: ...
-    def select_for_update(self, nowait: bool = ..., skip_locked: bool = ..., of: Tuple = ...) -> QuerySet[_T, _Row]: ...
-    def select_related(self, *fields: Any) -> QuerySet[_T, _Row]: ...
-    def prefetch_related(self, *lookups: Any) -> QuerySet[_T, _Row]: ...
+    def union(self, *other_qs: Any, all: bool = ...) -> ValuesQuerySet[_T, _Row]: ...
+    def intersection(self, *other_qs: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def difference(self, *other_qs: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def select_for_update(
+        self, nowait: bool = ..., skip_locked: bool = ..., of: Tuple = ...
+    ) -> ValuesQuerySet[_T, _Row]: ...
+    def select_related(self, *fields: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def prefetch_related(self, *lookups: Any) -> ValuesQuerySet[_T, _Row]: ...
    # TODO: return type
-    def annotate(self, *args: Any, **kwargs: Any) -> QuerySet[Any, Any]: ...
-    def order_by(self, *field_names: Any) -> QuerySet[_T, _Row]: ...
-    def distinct(self, *field_names: Any) -> QuerySet[_T, _Row]: ...
+    def annotate(self, *args: Any, **kwargs: Any) -> QuerySet[Any]: ...
+    def order_by(self, *field_names: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def distinct(self, *field_names: Any) -> ValuesQuerySet[_T, _Row]: ...
    # extra() return type won't be supported any time soon
    def extra(
        self,
@@ -138,18 +194,11 @@ class QuerySet(Generic[_T, _Row], Collection[_Row], Sized):
        tables: Optional[List[str]] = ...,
        order_by: Optional[Sequence[str]] = ...,
        select_params: Optional[Sequence[Any]] = ...,
-    ) -> QuerySet[Any, Any]: ...
-    def reverse(self) -> QuerySet[_T, _Row]: ...
-    def defer(self, *fields: Any) -> QuerySet[_T, _Row]: ...
-    def only(self, *fields: Any) -> QuerySet[_T, _Row]: ...
-    def using(self, alias: Optional[str]) -> QuerySet[_T, _Row]: ...
-    @property
-    def ordered(self) -> bool: ...
-    @property
-    def db(self) -> str: ...
-    def resolve_expression(self, *args: Any, **kwargs: Any) -> Any: ...
-    # TODO: remove when django adds __class_getitem__ methods
-    def __getattr__(self, item: str) -> Any: ...
+    ) -> QuerySet[Any]: ...
+    def reverse(self) -> ValuesQuerySet[_T, _Row]: ...
+    def defer(self, *fields: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def only(self, *fields: Any) -> ValuesQuerySet[_T, _Row]: ...
+    def using(self, alias: Optional[str]) -> ValuesQuerySet[_T, _Row]: ...

 class RawQuerySet(Iterable[_T], Sized):
    query: RawQuery
--- a/django-stubs/shortcuts.pyi
+++ b/django-stubs/shortcuts.pyi
@@ -31,6 +31,6 @@ def redirect(

 _T = TypeVar("_T", bound=Model)

-def get_object_or_404(klass: Union[Type[_T], Manager[_T], QuerySet[_T, _T]], *args: Any, **kwargs: Any) -> _T: ...
-def get_list_or_404(klass: Union[Type[_T], Manager[_T], QuerySet[_T, _T]], *args: Any, **kwargs: Any) -> List[_T]: ...
+def get_object_or_404(klass: Union[Type[_T], Manager[_T], QuerySet[_T]], *args: Any, **kwargs: Any) -> _T: ...
+def get_list_or_404(klass: Union[Type[_T], Manager[_T], QuerySet[_T]], *args: Any, **kwargs: Any) -> List[_T]: ...
 def resolve_url(to: Union[Callable, Model, str], *args: Any, **kwargs: Any) -> str: ...
--- a/mypy_django_plugin/main.py
+++ b/mypy_django_plugin/main.py
@@ -7,7 +7,7 @@ from mypy.errors import Errors
 from mypy.nodes import MypyFile, TypeInfo
 from mypy.options import Options
 from mypy.plugin import (
-    AnalyzeTypeContext, AttributeContext, ClassDefContext, FunctionContext, MethodContext, Plugin,
+    AttributeContext, ClassDefContext, FunctionContext, MethodContext, Plugin,
 )
 from mypy.types import Type as MypyType

@@ -233,15 +233,6 @@ class NewSemanalDjangoPlugin(Plugin):
            return partial(request.set_auth_user_model_as_type_for_request_user, django_context=self.django_context)
        return None

-    def get_type_analyze_hook(self, fullname: str
-                              ) -> Optional[Callable[[AnalyzeTypeContext], MypyType]]:
-        info = self._get_typeinfo_or_none(fullname)
-        if (info
-                and info.has_base(fullnames.QUERYSET_CLASS_FULLNAME)
-                and not info.has_base(fullnames.BASE_MANAGER_CLASS_FULLNAME)):
-            return partial(querysets.set_first_generic_param_as_default_for_second, fullname=fullname)
-        return None
-

 def plugin(version):
    return NewSemanalDjangoPlugin
--- a/mypy_django_plugin/transformers/querysets.py
+++ b/mypy_django_plugin/transformers/querysets.py
@@ -1,15 +1,12 @@
 from collections import OrderedDict
-from typing import List, Optional, Sequence, Type, Union, cast
+from typing import List, Optional, Sequence, Type, Union

 from django.core.exceptions import FieldError
 from django.db.models.base import Model
 from django.db.models.fields.related import RelatedField
-from mypy.newsemanal.typeanal import TypeAnalyser
-from mypy.nodes import Expression, NameExpr, TypeInfo
-from mypy.plugin import AnalyzeTypeContext, FunctionContext, MethodContext
-from mypy.types import AnyType, Instance
-from mypy.types import Type as MypyType
-from mypy.types import TypeOfAny
+from mypy.nodes import Expression, NameExpr
+from mypy.plugin import FunctionContext, MethodContext
+from mypy.types import AnyType, Instance, Type as MypyType, TypeOfAny

 from mypy_django_plugin.django.context import DjangoContext
 from mypy_django_plugin.lib import fullnames, helpers
@@ -183,20 +180,3 @@ def extract_proper_type_queryset_values(ctx: MethodContext, django_context: Djan

    row_type = helpers.make_typeddict(ctx.api, column_types, set(column_types.keys()))
    return helpers.reparametrize_instance(ctx.default_return_type, [model_type, row_type])
-
-
-def set_first_generic_param_as_default_for_second(ctx: AnalyzeTypeContext, fullname: str) -> MypyType:
-    type_analyser_api = cast(TypeAnalyser, ctx.api)
-
-    info = helpers.lookup_fully_qualified_typeinfo(type_analyser_api.api, fullname)  # type: ignore
-    assert isinstance(info, TypeInfo)
-
-    if not ctx.type.args:
-        return Instance(info, [AnyType(TypeOfAny.explicit), AnyType(TypeOfAny.explicit)])
-
-    args = ctx.type.args
-    if len(args) == 1:
-        args = [args[0], args[0]]
-
-    analyzed_args = [type_analyser_api.analyze_type(arg) for arg in args]
-    return Instance(info, analyzed_args)
--- a/scripts/enabled_test_modules.py
+++ b/scripts/enabled_test_modules.py
@@ -28,7 +28,6 @@ IGNORED_ERRORS = {
        'Cannot assign to a type',
        '"HttpResponse" has no attribute',
        '"HttpResponseBase" has no attribute',
-        # '"HttpRequest" has no attribute',
        '"object" has no attribute',
        'defined in the current module',
        re.compile(r'"Callable\[(\[(Any(, )?)*((, )?VarArg\(Any\))?((, )?KwArg\(Any\))?\]|\.\.\.), Any\]" '
@@ -73,6 +72,12 @@ IGNORED_ERRORS = {
        'Incompatible types in assignment (expression has type "Callable[',
        'SimpleLazyObject'
    ],
+    'aggregation': [
+        re.compile(r'got "Optional\[(Author|Publisher)\]", expected "Union\[(Author|Publisher), Combinable\]"')
+    ],
+    'annotations': [
+        'Incompatible type for "store" of "Employee" (got "Optional[Store]", expected "Union[Store, Combinable]")'
+    ],
    'apps': [
        'Incompatible types in assignment (expression has type "str", target has type "type")',
    ],
@@ -114,7 +119,8 @@ IGNORED_ERRORS = {
    'custom_managers': [
        'Unsupported dynamic base class',
        '"Book" has no attribute "favorite_avg"',
-        'Incompatible types in assignment (expression has type "CharField'
+        'Incompatible types in assignment (expression has type "CharField',
+        'Item "Book" of "Optional[Book]" has no attribute "favorite_avg"'
    ],
    'csrf_tests': [
        'Incompatible types in assignment (expression has type "property", ' +
@@ -135,6 +141,7 @@ IGNORED_ERRORS = {
    ],
    'db_functions': [
        '"FloatModel" has no attribute',
+        'Incompatible types in assignment (expression has type "Optional[Any]", variable has type "FloatModel")'
    ],
    'decorators': [
        '"Type[object]" has no attribute "method"'
@@ -164,9 +171,9 @@ IGNORED_ERRORS = {
    ],
    'get_object_or_404': [
        'Argument 1 to "get_object_or_404" has incompatible type "str"; '
-        + 'expected "Union[Type[<nothing>], QuerySet[<nothing>, <nothing>]]"',
+        + 'expected "Union[Type[<nothing>], QuerySet[<nothing>]]"',
        'Argument 1 to "get_list_or_404" has incompatible type "List[Type[Article]]"; '
-        + 'expected "Union[Type[<nothing>], QuerySet[<nothing>, <nothing>]]"',
+        + 'expected "Union[Type[<nothing>], QuerySet[<nothing>]]"',
        'CustomClass'
    ],
    'generic_relations_regress': [
@@ -234,7 +241,9 @@ IGNORED_ERRORS = {
        '"Dimension" has no attribute "set_component_order"',
    ],
    'one_to_one': [
-        'expression has type "None", variable has type "UndergroundBar"'
+        'expression has type "None", variable has type "UndergroundBar"',
+        'Item "OneToOneField[Union[Place, Combinable], Place]" '
+        + 'of "Union[OneToOneField[Union[Place, Combinable], Place], Any]"',
    ],
    'postgres_tests': [
        'DummyArrayField',
@@ -255,9 +264,9 @@ IGNORED_ERRORS = {
        '"Person" has no attribute "houses_lst"',
        '"Book" has no attribute "first_authors"',
        '"Book" has no attribute "the_authors"',
-        'Incompatible types in assignment (expression has type "List[Room]", variable has type "QuerySet[Room, Room]")',
-        '"Room" has no attribute "main_room_of_attr"',
-        '"Room" has no attribute "house_attr"'
+        'Incompatible types in assignment (expression has type "List[Room]", variable has type "QuerySet[Room]")',
+        'Item "Room" of "Optional[Room]" has no attribute "house_attr"',
+        'Item "Room" of "Optional[Room]" has no attribute "main_room_of_attr"'
    ],
    'proxy_models': [
        'Incompatible types in assignment',
@@ -266,8 +275,8 @@ IGNORED_ERRORS = {
    'queries': [
        'Incompatible types in assignment (expression has type "None", variable has type "str")',
        'Invalid index type "Optional[str]" for "Dict[str, int]"; expected type "str"',
-        'Unsupported operand types for & ("QuerySet[Author, Author]" and "QuerySet[Tag, Tag]")',
-        'Unsupported operand types for | ("QuerySet[Author, Author]" and "QuerySet[Tag, Tag]")',
+        'Unsupported operand types for & ("QuerySet[Author]" and "QuerySet[Tag]")',
+        'Unsupported operand types for | ("QuerySet[Author]" and "QuerySet[Tag]")',
        'ObjectA',
        'ObjectB',
        'ObjectC',
@@ -293,6 +302,10 @@ IGNORED_ERRORS = {
        'Incompatible types in assignment (expression has type "None", variable has type "int")',
        '"AbstractBaseSession" has no attribute'
    ],
+    'select_related': [
+        'Item "ForeignKey[Union[Genus, Combinable], Genus]" '
+        + 'of "Union[ForeignKey[Union[Genus, Combinable], Genus], Any]"'
+    ],
    'select_related_onetoone': [
        'Incompatible types in assignment (expression has type "Parent2", variable has type "Parent1")',
        '"Parent1" has no attribute'
--- a/test-data/typecheck/managers/querysets/test_basic_methods.yml
+++ b/test-data/typecheck/managers/querysets/test_basic_methods.yml
@@ -3,22 +3,22 @@
        from myapp.models import Blog

        qs = Blog.objects.all()
-        reveal_type(qs) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*, myapp.models.Blog*]'
+        reveal_type(qs) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*]'
        reveal_type(qs.get(id=1)) # N: Revealed type is 'myapp.models.Blog*'
        reveal_type(iter(qs)) # N: Revealed type is 'typing.Iterator[myapp.models.Blog*]'
        reveal_type(qs.iterator()) # N: Revealed type is 'typing.Iterator[myapp.models.Blog*]'
-        reveal_type(qs.first()) # N: Revealed type is 'myapp.models.Blog*'
+        reveal_type(qs.first()) # N: Revealed type is 'Union[myapp.models.Blog*, None]'
        reveal_type(qs.earliest()) # N: Revealed type is 'myapp.models.Blog*'
        reveal_type(qs[0]) # N: Revealed type is 'myapp.models.Blog*'
-        reveal_type(qs[:9]) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*, myapp.models.Blog*]'
+        reveal_type(qs[:9]) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*]'
        reveal_type(qs.in_bulk()) # N: Revealed type is 'builtins.dict[Any, myapp.models.Blog*]'

        # .dates / .datetimes
-        reveal_type(Blog.objects.dates("created_at", "day")) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*, datetime.date]'
-        reveal_type(Blog.objects.datetimes("created_at", "day")) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*, datetime.datetime]'
+        reveal_type(Blog.objects.dates("created_at", "day")) # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Blog*, datetime.date]'
+        reveal_type(Blog.objects.datetimes("created_at", "day")) # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Blog*, datetime.datetime]'

        # AND-ing QuerySets
-        reveal_type(Blog.objects.all() & Blog.objects.all()) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*, myapp.models.Blog*]'
+        reveal_type(Blog.objects.all() & Blog.objects.all()) # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog*]'
    installed_apps:
        - myapp
    files:
@@ -28,11 +28,4 @@
                from django.db import models

                class Blog(models.Model):
-                    created_at = models.DateTimeField()
-
-   case: queryset_could_be_specified_with_one_type
-    main: |
-        from typing import Optional
-        from django.db import models
-        queryset: models.QuerySet[models.Model] = models.QuerySet()
-        reveal_type(queryset)  # N: Revealed type is 'django.db.models.query.QuerySet[django.db.models.base.Model, django.db.models.base.Model]'
+                    created_at = models.DateTimeField()
--- a/test-data/typecheck/managers/querysets/test_values_list.yml
+++ b/test-data/typecheck/managers/querysets/test_values_list.yml
@@ -192,8 +192,8 @@
 -   case: values_list_flat_true_with_ids
    main: |
        from myapp.models import Blog, Publisher
-        reveal_type(Blog.objects.values_list('id', flat=True))  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog, builtins.int]'
-        reveal_type(Blog.objects.values_list('publisher_id', flat=True))  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Blog, builtins.int]'
+        reveal_type(Blog.objects.values_list('id', flat=True))  # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Blog, builtins.int]'
+        reveal_type(Blog.objects.values_list('publisher_id', flat=True))  # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Blog, builtins.int]'
    installed_apps:
        - myapp
    files:
@@ -210,8 +210,8 @@
    main: |
        from myapp.models import TransactionQuerySet
        reveal_type(TransactionQuerySet())  # N: Revealed type is 'myapp.models.TransactionQuerySet'
-        reveal_type(TransactionQuerySet().values())  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Transaction, TypedDict({'id': builtins.int, 'total': builtins.int})]'
-        reveal_type(TransactionQuerySet().values_list())  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.Transaction, Tuple[builtins.int, builtins.int]]'
+        reveal_type(TransactionQuerySet().values())  # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Transaction, TypedDict({'id': builtins.int, 'total': builtins.int})]'
+        reveal_type(TransactionQuerySet().values_list())  # N: Revealed type is 'django.db.models.query.ValuesQuerySet[myapp.models.Transaction, Tuple[builtins.int, builtins.int]]'
    installed_apps:
        - myapp
    files:
--- a/test-data/typecheck/managers/test_managers.yml
+++ b/test-data/typecheck/managers/test_managers.yml
@@ -197,10 +197,10 @@
    main: |
        from myapp.models import UnrelatedModel, MyModel
        reveal_type(UnrelatedModel.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.UnrelatedModel]'
-        reveal_type(UnrelatedModel.objects.first()) # N: Revealed type is 'myapp.models.UnrelatedModel*'
+        reveal_type(UnrelatedModel.objects.first()) # N: Revealed type is 'Union[myapp.models.UnrelatedModel*, None]'

        reveal_type(MyModel.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.MyModel]'
-        reveal_type(MyModel.objects.first()) # N: Revealed type is 'myapp.models.MyModel*'
+        reveal_type(MyModel.objects.first()) # N: Revealed type is 'Union[myapp.models.MyModel*, None]'
    installed_apps:
        - myapp
    files:
@@ -218,10 +218,10 @@
    main: |
        from myapp.models import UnrelatedModel2, MyModel2
        reveal_type(UnrelatedModel2.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.UnrelatedModel2]'
-        reveal_type(UnrelatedModel2.objects.first()) # N: Revealed type is 'myapp.models.UnrelatedModel2*'
+        reveal_type(UnrelatedModel2.objects.first()) # N: Revealed type is 'Union[myapp.models.UnrelatedModel2*, None]'

        reveal_type(MyModel2.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.MyModel2]'
-        reveal_type(MyModel2.objects.first()) # N: Revealed type is 'myapp.models.MyModel2*'
+        reveal_type(MyModel2.objects.first()) # N: Revealed type is 'Union[myapp.models.MyModel2*, None]'
    installed_apps:
        - myapp
    files:
@@ -239,10 +239,10 @@
    main: |
        from myapp.models import ParentOfMyModel3, MyModel3
        reveal_type(ParentOfMyModel3.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.ParentOfMyModel3]'
-        reveal_type(ParentOfMyModel3.objects.first()) # N: Revealed type is 'myapp.models.ParentOfMyModel3*'
+        reveal_type(ParentOfMyModel3.objects.first()) # N: Revealed type is 'Union[myapp.models.ParentOfMyModel3*, None]'

        reveal_type(MyModel3.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.MyModel3]'
-        reveal_type(MyModel3.objects.first()) # N: Revealed type is 'myapp.models.MyModel3*'
+        reveal_type(MyModel3.objects.first()) # N: Revealed type is 'Union[myapp.models.MyModel3*, None]'
    installed_apps:
        - myapp
    files:
@@ -260,10 +260,10 @@
    main: |
        from myapp.models import ParentOfMyModel4, MyModel4
        reveal_type(ParentOfMyModel4.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.ParentOfMyModel4]'
-        reveal_type(ParentOfMyModel4.objects.first()) # N: Revealed type is 'myapp.models.ParentOfMyModel4*'
+        reveal_type(ParentOfMyModel4.objects.first()) # N: Revealed type is 'Union[myapp.models.ParentOfMyModel4*, None]'

        reveal_type(MyModel4.objects) # N: Revealed type is 'django.db.models.manager.Manager[myapp.models.MyModel4]'
-        reveal_type(MyModel4.objects.first()) # N: Revealed type is 'myapp.models.MyModel4*'
+        reveal_type(MyModel4.objects.first()) # N: Revealed type is 'Union[myapp.models.MyModel4*, None]'
    installed_apps:
        - myapp
    files:
@@ -308,7 +308,7 @@
    main: |
        from myapp.models import User
        reveal_type(User.objects.get())  # N: Revealed type is 'myapp.models.User*'
-        reveal_type(User.objects.select_related())  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.User*, myapp.models.User*]'
+        reveal_type(User.objects.select_related())  # N: Revealed type is 'django.db.models.query.QuerySet[myapp.models.User*]'
    installed_apps:
        - myapp
    files: