Use Self type from PEP 673 everywhere (#183)

This PR makes consistent use of the `Self` type. It also removes version checks for `from typing_extensions Self` and others as typing_extentions is considered a builtin module in stubs by all major type checkers (see typeshed). I added an isort option to reflect that fact similar to what is done in the typeshed project.

django-stubs/contrib/admin/options.pyi

@@ -15,6 +15,7 @@ from typing import (
     TypeVar,
     Union,
 )
+from typing_extensions import Literal, TypedDict
 
 from django.contrib.admin.filters import ListFilter
 from django.contrib.admin.models import LogEntry
@@ -47,7 +48,6 @@ from django.http.response import (
 from django.template.response import TemplateResponse
 from django.urls.resolvers import URLPattern
 from django.utils.safestring import SafeText
-from typing_extensions import Literal, TypedDict
 
 IS_POPUP_VAR: str
 TO_FIELD_VAR: str

django-stubs/contrib/auth/base_user.pyi

@@ -1,15 +1,10 @@
-import sys
 from typing import Any, List, Optional, Tuple, TypeVar, Union, overload
+from typing_extensions import Literal
 
 from django.db import models
 from django.db.models.base import Model
 from django.db.models.fields import BooleanField
 
-if sys.version_info < (3, 8):
-    from typing_extensions import Literal
-else:
-    from typing import Literal
-
 _T = TypeVar("_T", bound=Model)
 
 class BaseUserManager(models.Manager[_T]):

django-stubs/contrib/auth/models.pyi

@@ -1,5 +1,5 @@
-import sys
 from typing import Any, ClassVar, Collection, Optional, Set, Tuple, Type, TypeVar, Union
+from typing_extensions import Literal, Self
 
 from django.contrib.auth.backends import ModelBackend
 from django.contrib.auth.base_user import AbstractBaseUser as AbstractBaseUser
@@ -10,16 +10,6 @@ from django.db import models
 from django.db.models.base import Model
 from django.db.models.manager import EmptyManager
 
-if sys.version_info < (3, 8):
-    from typing_extensions import Literal
-else:
-    from typing import Literal
-
-if sys.version_info < (3, 11):
-    from typing_extensions import Self
-else:
-    from typing import Self
-
 _AnyUser = Union[Model, "AnonymousUser"]
 
 def update_last_login(

django-stubs/contrib/contenttypes/fields.pyi

@@ -1,4 +1,5 @@
 from typing import Any, Callable, Dict, List, Optional, Tuple, Type, Union
+from typing_extensions import Self
 
 from django.contrib.contenttypes.models import ContentType
 from django.core.checks.messages import CheckMessage
@@ -84,7 +85,7 @@ class GenericRelation(ForeignObject[Any]):
     content_type_field_name: Any = ...
     for_concrete_model: Any = ...
     to_fields: Any = ...
-    def __new__(cls, *args: Any, **kwargs: Any) -> GenericRelation: ...
+    def __new__(cls, *args: Any, **kwargs: Any) -> Self: ...
     def __init__(
         self,
         to: Union[Type[Model], str],

django-stubs/contrib/humanize/templatetags/humanize.pyi

@@ -1,6 +1,6 @@
 from datetime import date
 from datetime import datetime as datetime
-from typing import Any, Callable, Dict, Optional, SupportsInt, Tuple, Type, Union
+from typing import Any, Callable, Dict, Optional, SupportsInt, Tuple, Union
 
 from django import template
 
@@ -21,4 +21,4 @@ class NaturalTimeFormatter:
     past_substrings: Dict[str, str]
     future_substrings: Dict[str, str]
     @classmethod
-    def string_for(cls: Type[NaturalTimeFormatter], value: Any) -> Any: ...
+    def string_for(cls, value: Any) -> Any: ...

django-stubs/contrib/postgres/fields/array.pyi

@@ -10,10 +10,10 @@ from typing import (
     Union,
     overload,
 )
+from typing_extensions import Literal
 
 from django.db.models.expressions import Combinable
 from django.db.models.fields import Field, _ErrorMessagesToOverride, _ValidatorCallable
-from typing_extensions import Literal
 
 from .mixins import CheckFieldDefaultMixin
 

django-stubs/contrib/postgres/fields/citext.pyi

@@ -9,9 +9,9 @@ from typing import (
     Union,
     overload,
 )
+from typing_extensions import Literal
 
 from django.db.models.fields import CharField, EmailField, TextField
-from typing_extensions import Literal
 
 _Choice = Tuple[Any, Any]
 _ChoiceNamedGroup = Tuple[str, Iterable[_Choice]]
@@ -75,8 +75,8 @@ class CICharField(CIText, CharField[_C]):
         validators: Iterable[_ValidatorCallable] = ...,
         error_messages: Optional[_ErrorMessagesToOverride] = ...,
     ) -> None: ...
-    def __get__(self: CICharField[_C], instance: Any, owner: Any) -> _C: ...
-    def __set__(self: CICharField[_C], instance: Any, value: _C) -> None: ...  # type: ignore [override]
+    def __get__(self, instance: Any, owner: Any) -> _C: ...
+    def __set__(self, instance: Any, value: _C) -> None: ...  # type: ignore [override]
 
 class CIEmailField(CIText, EmailField[_C]):
     @overload
@@ -129,7 +129,7 @@ class CIEmailField(CIText, EmailField[_C]):
         validators: Iterable[_ValidatorCallable] = ...,
         error_messages: Optional[_ErrorMessagesToOverride] = ...,
     ) -> None: ...
-    def __get__(self: CIEmailField[_C], instance: Any, owner: Any) -> _C: ...
+    def __get__(self, instance: Any, owner: Any) -> _C: ...
     def __set__(self, instance: Any, value: _C) -> None: ...  # type: ignore [override]
 
 class CITextField(CIText, TextField[_C]):
@@ -183,5 +183,5 @@ class CITextField(CIText, TextField[_C]):
         validators: Iterable[_ValidatorCallable] = ...,
         error_messages: Optional[_ErrorMessagesToOverride] = ...,
     ) -> None: ...
-    def __get__(self: CITextField[_C], instance: Any, owner: Any) -> _C: ...
-    def __set__(self: CITextField[_C], instance: Any, value: _C) -> None: ...  # type: ignore [override]
+    def __get__(self, instance: Any, owner: Any) -> _C: ...
+    def __set__(self, instance: Any, value: _C) -> None: ...  # type: ignore [override]

django-stubs/contrib/postgres/fields/hstore.pyi

@@ -10,9 +10,9 @@ from typing import (
     Union,
     overload,
 )
+from typing_extensions import Literal
 
 from django.db.models import Field, Transform
-from typing_extensions import Literal
 
 from .mixins import CheckFieldDefaultMixin
 
@@ -76,8 +76,8 @@ class HStoreField(Generic[_T], CheckFieldDefaultMixin, Field[Any, Any]):
         error_messages: Optional[_ErrorMessagesToOverride] = ...,
     ) -> None: ...
     def get_transform(self, name: Any) -> Any: ...
-    def __get__(self: HStoreField[_T], instance: Any, owner: Any) -> _T: ...
-    def __set__(self: HStoreField[_T], instance: Any, value: _T) -> None: ...
+    def __get__(self, instance: Any, owner: Any) -> _T: ...
+    def __set__(self, instance: Any, value: _T) -> None: ...
 
 class KeyTransform(Transform):
     def __init__(self, key_name: str, *args: Any, **kwargs: Any) -> None: ...

django-stubs/contrib/postgres/search.pyi

@@ -1,4 +1,5 @@
-from typing import Any, Dict, Iterable, Optional, TypeVar, Union
+from typing import Any, Dict, Iterable, Optional, Union
+from typing_extensions import Self
 
 from django.db.models import Field
 from django.db.models.expressions import (
@@ -88,15 +89,13 @@ class CombinedSearchVector(SearchVectorCombinable, CombinedExpression):
         output_field: Optional[_OutputField] = ...,
     ) -> None: ...
 
-_T = TypeVar("_T", bound="SearchQueryCombinable")
-
 class SearchQueryCombinable:
     BITAND: str = ...
     BITOR: str = ...
-    def __or__(self: _T, other: SearchQueryCombinable) -> _T: ...
-    def __ror__(self: _T, other: SearchQueryCombinable) -> _T: ...
-    def __and__(self: _T, other: SearchQueryCombinable) -> _T: ...
-    def __rand__(self: _T, other: SearchQueryCombinable) -> _T: ...
+    def __or__(self, other: SearchQueryCombinable) -> Self: ...
+    def __ror__(self, other: SearchQueryCombinable) -> Self: ...
+    def __and__(self, other: SearchQueryCombinable) -> Self: ...
+    def __rand__(self, other: SearchQueryCombinable) -> Self: ...
 
 class SearchQuery(SearchQueryCombinable, Value):  # type: ignore
     SEARCH_TYPES: Dict[str, str] = ...
@@ -109,7 +108,7 @@ class SearchQuery(SearchQueryCombinable, Value):  # type: ignore
         invert: bool = ...,
         search_type: str = ...
     ) -> None: ...
-    def __invert__(self: _T) -> _T: ...
+    def __invert__(self) -> Self: ...
 
 class CombinedSearchQuery(SearchQueryCombinable, CombinedExpression):  # type: ignore
     def __init__(

django-stubs/contrib/staticfiles/finders.pyi

@@ -1,8 +1,8 @@
 from typing import Any, Iterable, Iterator, List, Mapping, Optional, Union, overload
+from typing_extensions import Literal
 
 from django.core.checks.messages import CheckMessage
 from django.core.files.storage import Storage
-from typing_extensions import Literal
 
 searched_locations: Any
 

django-stubs/core/files/base.pyi

@@ -1,11 +1,10 @@
 import types
 from io import StringIO
-from typing import IO, Any, Iterator, Optional, Type, TypeVar, Union
+from typing import IO, Any, Iterator, Optional, Type, Union
+from typing_extensions import Self
 
 from django.core.files.utils import FileProxyMixin
 
-_T = TypeVar("_T", bound="File")
-
 class File(FileProxyMixin, IO[Any]):
     DEFAULT_CHUNK_SIZE: Any = ...
     file: IO[Any] = ...
@@ -20,14 +19,14 @@ class File(FileProxyMixin, IO[Any]):
     def multiple_chunks(self, chunk_size: Optional[int] = ...) -> bool: ...
     def __iter__(self) -> Iterator[Union[bytes, str]]: ...
     def __next__(self) -> Union[bytes, str]: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self) -> Self: ...
     def __exit__(
         self,
         exc_type: Optional[Type[BaseException]],
         exc_value: Optional[BaseException],
         tb: Optional[types.TracebackType],
     ) -> None: ...
-    def open(self: _T, mode: Optional[str] = ...) -> _T: ...
+    def open(self, mode: Optional[str] = ...) -> Self: ...
     def close(self) -> None: ...
 
 class ContentFile(File):

django-stubs/core/files/uploadedfile.pyi

@@ -45,4 +45,4 @@ class SimpleUploadedFile(InMemoryUploadedFile):
         self, name: str, content: Optional[Union[bytes, str]], content_type: str = ...
     ) -> None: ...
     @classmethod
-    def from_dict(cls: Any, file_dict: Dict[str, Union[str, bytes]]) -> None: ...
+    def from_dict(cls, file_dict: Dict[str, Union[str, bytes]]) -> None: ...

django-stubs/core/mail/backends/base.pyi

@@ -1,15 +1,14 @@
 import types
-from typing import Any, Iterable, Optional, Type, TypeVar
+from typing import Any, Iterable, Optional, Type
+from typing_extensions import Self
 
 from django.core.mail.message import EmailMessage
 
-_T = TypeVar("_T", bound="BaseEmailBackend")
-
 class BaseEmailBackend:
     def __init__(self, fail_silently: bool = ..., **kwargs: Any) -> None: ...
     def open(self) -> Optional[bool]: ...
     def close(self) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self) -> Self: ...
     def __exit__(
         self,
         exc_type: Type[BaseException],

django-stubs/db/backends/utils.pyi

@@ -14,12 +14,12 @@ from typing import (
     Type,
     Union,
 )
+from typing_extensions import Literal
 from uuid import UUID
 
 import psycopg2
 from django.db.backends.postgresql.base import DatabaseWrapper
 from psycopg2.extensions import Column
-from typing_extensions import Literal
 
 logger: Any
 

django-stubs/db/migrations/migration.pyi

@@ -1,4 +1,5 @@
 from typing import List, Optional, Tuple
+from typing_extensions import Self
 
 from django.db.backends.base.schema import BaseDatabaseSchemaEditor
 from django.db.migrations.operations.base import Operation
@@ -32,6 +33,6 @@ class Migration:
 
 class SwappableTuple(Tuple[str, str]):
     setting: str = ...
-    def __new__(cls, value: Tuple[str, str], setting: str) -> SwappableTuple: ...
+    def __new__(cls, value: Tuple[str, str], setting: str) -> Self: ...
 
 def swappable_dependency(value: str) -> SwappableTuple: ...

django-stubs/db/models/base.pyi

@@ -1,4 +1,3 @@
-import sys
 from typing import (
     Any,
     Callable,
@@ -11,9 +10,9 @@ from typing import (
     Set,
     Tuple,
     Type,
-    TypeVar,
     Union,
 )
+from typing_extensions import Self
 
 from django.core.checks.messages import CheckMessage
 from django.core.exceptions import (
@@ -23,14 +22,6 @@ from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.db.models.manager import BaseManager
 from django.db.models.options import Options
 
-if sys.version_info < (3, 11):
-    from typing_extensions import Self
-else:
-    from typing import Self
-
-_M = TypeVar("_M", bound=Any)
-_Self = TypeVar("_Self", bound="Model")
-
 class ModelStateFieldsCacheDescriptor: ...
 
 class ModelState:
@@ -55,11 +46,8 @@ class Model(metaclass=ModelBase):
     def add_to_class(cls, name: str, value: Any) -> Any: ...
     @classmethod
     def from_db(
-        cls: Type[_Self],
-        db: Optional[str],
-        field_names: Collection[str],
-        values: Collection[Any],
-    ) -> _Self: ...
+        cls, db: Optional[str], field_names: Collection[str], values: Collection[Any]
+    ) -> Self: ...
     def delete(
         self, using: Any = ..., keep_parents: bool = ...
     ) -> Tuple[int, Dict[str, int]]: ...
@@ -76,8 +64,8 @@ class Model(metaclass=ModelBase):
     def clean_fields(self, exclude: Optional[Collection[str]] = ...) -> None: ...
     def validate_unique(self, exclude: Optional[Collection[str]] = ...) -> None: ...
     def unique_error_message(
-        self: _Self,
-        model_class: Type[_Self],
+        self,
+        model_class: Type[Self],
         unique_check: Collection[Union[Callable[..., Any], str]],
     ) -> ValidationError: ...
     def save(

django-stubs/db/models/constraints.pyi

@@ -1,13 +1,12 @@
 from enum import Enum
-from typing import Any, Optional, Sequence, Tuple, Type, TypeVar, Union
+from typing import Any, Optional, Sequence, Tuple, Type, Union
+from typing_extensions import Self
 
 from django.db.backends.base.schema import BaseDatabaseSchemaEditor
 from django.db.models.base import Model
 from django.db.models.expressions import BaseExpression, Combinable
 from django.db.models.query_utils import Q
 
-_T = TypeVar("_T", bound="BaseConstraint")
-
 class Deferrable(Enum):
     DEFERRED: str
     IMMEDIATE: str
@@ -36,7 +35,7 @@ class BaseConstraint:
         schema_editor: Optional[BaseDatabaseSchemaEditor],
     ) -> str: ...
     def deconstruct(self) -> Any: ...
-    def clone(self: _T) -> _T: ...
+    def clone(self) -> Self: ...
 
 class CheckConstraint(BaseConstraint):
     check: Q