Use AbstractBaseUser where possible (#475)

Fixes #431

django-stubs/contrib/auth/__init__.pyi

@@ -2,7 +2,7 @@ from typing import Any, List, Optional, Type, Union
 
 from django.contrib.auth.backends import ModelBackend
 from django.contrib.auth.base_user import AbstractBaseUser
-from django.contrib.auth.models import AbstractUser, AnonymousUser
+from django.contrib.auth.models import AnonymousUser
 from django.core.handlers.wsgi import WSGIRequest
 from django.db.models.base import Model
 from django.db.models.options import Options
@@ -29,6 +29,6 @@ def logout(request: HttpRequest) -> None: ...
 def get_user_model() -> Type[Model]: ...
 def get_user(request: HttpRequest) -> Union[AbstractBaseUser, AnonymousUser]: ...
 def get_permission_codename(action: str, opts: Options) -> str: ...
-def update_session_auth_hash(request: HttpRequest, user: AbstractUser) -> None: ...
+def update_session_auth_hash(request: HttpRequest, user: AbstractBaseUser) -> None: ...
 
 default_app_config: str

django-stubs/contrib/auth/forms.pyi

@@ -1,7 +1,7 @@
 from typing import Any, Dict, Iterator, Optional
 
 from django.contrib.auth.base_user import AbstractBaseUser
-from django.contrib.auth.models import AbstractUser, User
+from django.contrib.auth.models import User
 from django.contrib.auth.tokens import PasswordResetTokenGenerator
 from django.core.exceptions import ValidationError
 from django.core.handlers.wsgi import WSGIRequest
@@ -86,6 +86,6 @@ class AdminPasswordChangeForm(forms.Form):
     password1: Any = ...
     password2: Any = ...
     user: User = ...
-    def __init__(self, user: AbstractUser, *args: Any, **kwargs: Any) -> None: ...
+    def __init__(self, user: AbstractBaseUser, *args: Any, **kwargs: Any) -> None: ...
     def clean_password2(self) -> str: ...
-    def save(self, commit: bool = ...) -> AbstractUser: ...
+    def save(self, commit: bool = ...) -> AbstractBaseUser: ...

django-stubs/test/client.pyi

@@ -2,7 +2,7 @@ from io import BytesIO
 from types import TracebackType
 from typing import Any, Dict, List, Optional, Pattern, Tuple, Type, Union
 
-from django.contrib.auth.models import AbstractUser
+from django.contrib.auth.base_user import AbstractBaseUser
 from django.contrib.sessions.backends.base import SessionBase
 from django.core.handlers.base import BaseHandler
 from django.http.cookie import SimpleCookie
@@ -126,7 +126,7 @@ class Client(RequestFactory):
     @property
     def session(self) -> SessionBase: ...
     def login(self, **credentials: Any) -> bool: ...
-    def force_login(self, user: AbstractUser, backend: Optional[str] = ...) -> None: ...
+    def force_login(self, user: AbstractBaseUser, backend: Optional[str] = ...) -> None: ...
     def logout(self) -> None: ...
 
 def conditional_content_removal(request: HttpRequest, response: HttpResponseBase) -> HttpResponse: ...