bump to 1.5.0

By declaring return type as -> Callable[[_C], _C], Mypy can infer that
the decorated function has also the same arguments and return type as
the original.

View functions are constrained to return HttpResponseBase (or any
subclass of it).

Also added typecheck test coverage to most of the cases.

CONTRIBUTING.md

@@ -0,0 +1,111 @@
+# How to contribute
+
+## Tutorials
+
+If you want to start working on this project,
+you will need to get familiar with these projects:
+
+- [Django docs](https://docs.djangoproject.com/en/dev/)
+- [Typing in Python](https://inventwithpython.com/blog/2019/11/24/type-hints-for-busy-python-programmers/)
+- [How to write custom mypy plugins](https://mypy.readthedocs.io/en/stable/extending_mypy.html)
+- [Typechecking Django and DRF](https://sobolevn.me/2019/08/typechecking-django-and-drf) guide
+- [Testing mypy stubs, plugins, and types](https://sobolevn.me/2019/08/testing-mypy-types) guide
+
+It is also recommended to take a look at these resources:
+
+- [Awesome Python Typing](https://github.com/typeddjango/awesome-python-typing)
+
+
+## Dev documentation
+
+TODO
+
+
+## Dependencies
+
+We use `pip` to manage the dependencies.
+
+To install them you would need to activate your `virtualenv` and run `install` command:
+
+```bash
+pip install -r ./dev-requirements.txt
+```
+
+
+## Tests and linters
+
+We use `mypy`, `pytest`, `flake8`, and `black` for quality control.
+Here's [how we run our CI](https://github.com/typeddjango/django-stubs/blob/master/.travis.yml).
+
+### Typechecking
+
+To run typechecking use:
+
+```bash
+mypy ./mypy_django_plugin
+```
+
+### Testing
+
+There are unit tests and type-related tests.
+
+To run unit tests:
+
+```bash
+pytest
+```
+
+Type-related tests ensure that different Django versions do work correctly.
+To run type-related tests:
+
+```bash
+python ./scripts/typecheck_tests.py --django_version=2.2
+python ./scripts/typecheck_tests.py --django_version=3.0
+```
+
+Currently we only support two Django versions.
+
+### Linting
+
+To run auto-formatting:
+
+```bash
+isort -rc .
+black django-stubs/
+```
+
+To run linting:
+
+```bash
+flake8
+flake8 --config flake8-pyi.ini
+```
+
+
+## Submitting your code
+
+We use [trunk based](https://trunkbaseddevelopment.com/)
+development (we also sometimes call it `wemake-git-flow`).
+
+What the point of this method?
+
+1. We use protected `master` branch,
+   so the only way to push your code is via pull request
+2. We use issue branches: to implement a new feature or to fix a bug
+   create a new branch named `issue-$TASKNUMBER`
+3. Then create a pull request to `master` branch
+4. We use `git tag`s to make releases, so we can track what has changed
+   since the latest release
+
+So, this way we achieve an easy and scalable development process
+which frees us from merging hell and long-living branches.
+
+In this method, the latest version of the app is always in the `master` branch.
+
+
+## Other help
+
+You can contribute by spreading a word about this library.
+It would also be a huge contribution to write
+a short article on how you are using this project.
+You can also share your best practices with us.

README.md

@@ -1,14 +1,12 @@
 <img src="http://mypy-lang.org/static/mypy_light.svg" alt="mypy logo" width="300px"/>
 
-# pep484 stubs for Django framework
+# Typesafe Django Framework
 
 [![Build Status](https://travis-ci.com/typeddjango/django-stubs.svg?branch=master)](https://travis-ci.com/typeddjango/django-stubs)
 [![Checked with mypy](http://www.mypy-lang.org/static/mypy_badge.svg)](http://mypy-lang.org/)
 [![Gitter](https://badges.gitter.im/mypy-django/Lobby.svg)](https://gitter.im/mypy-django/Lobby)
 
-This package contains type stubs and mypy plugin to provide more precise static types and type inference for Django framework. Django uses some Python "magic" that makes having precise types for some code patterns problematic. This is why we need to accompany the stubs with mypy plugins. The final goal is to be able to get precise types for most common patterns.
-
-Could be run on earlier versions of Django, but expect some missing imports warnings.
+This package contains [type stubs](https://www.python.org/dev/peps/pep-0561/) and a custom mypy plugin to provide more precise static types and type inference for Django framework. Django uses some Python "magic" that makes having precise types for some code patterns problematic. This is why we need this project. The final goal is to be able to get precise types for most common patterns.
 
 
 ## Installation
@@ -17,8 +15,35 @@ Could be run on earlier versions of Django, but expect some missing imports warn
 pip install django-stubs
 ```
 
+See [Configuration](#configuration) section to get started.
 
-## Mypy compatibility
+
+## Configuration
+
+To make `mypy` happy, you will need to add:
+
+```ini
+[mypy]
+plugins =
+    mypy_django_plugin.main
+    
+[mypy.plugins.django-stubs]
+django_settings_module = "myproject.settings"
+```
+
+in your `mypy.ini` or `setup.cfg` [file](https://mypy.readthedocs.io/en/latest/config_file.html).
+
+Two things happeining here:
+
+1. We need to explicitly list our plugin to be loaded by `mypy`
+2. Our plugin also requires `django` settings module (what you put into `DJANGO_SETTINGS_MODULE` variable) to be specified
+
+This fully working [typed boilerplate](https://github.com/wemake-services/wemake-django-template) can serve you as an example.
+
+
+## Version compatibility
+
+We rely on different `django` and `mypy` versions:
 
 | django-stubs | mypy version | django version | python version
 | ------------ | ---- | ---- | ---- |
@@ -28,58 +53,66 @@ pip install django-stubs
 | 0.12.x | old semantic analyzer (<0.711), dmypy support | 2.1.x | ^3.6
 
 
-## Configuration
+## FAQ
 
-To make mypy aware of the plugin, you need to add
+### Is this an official Django project?
 
-```ini
-[mypy]
-plugins =
-    mypy_django_plugin.main
-```
+No, it is not. We are indendepent from Django at the moment.
+There's a [proposal](https://github.com/django/deps/pull/65) to merge our project into the Django itself.
+You show your support by linking the PR.
 
-in your `mypy.ini` or `setup.cfg` [file](https://mypy.readthedocs.io/en/latest/config_file.html).
+### Is it safe to use this in production?
 
-Plugin also requires Django settings module (what you put into `DJANGO_SETTINGS_MODULE` variable) to be specified.
+Yes, it is! This project does not affect your runtime at all.
+It only affects `mypy` type checking process.
 
-```ini
-[mypy]
-strict_optional = True
+But, it does not make any sense to use this project without `mypy`.
 
-# This one is new:
-[mypy.plugins.django-stubs]
-django_settings_module = mysettings
-```
+### mypy crashes when I run it with this plugin installed
 
-Where `mysettings` is a value of `DJANGO_SETTINGS_MODULE` (with or without quotes)
-
-Current implementation uses Django runtime to extract models information, so it will crash, if your installed apps `models.py` is not correct. For this same reason, you cannot use `reveal_type` inside global scope of any Python file that will be executed for `django.setup()`. 
+Current implementation uses Django runtime to extract models information, so it will crash, if your installed apps or `models.py` is not correct. For this same reason, you cannot use `reveal_type` inside global scope of any Python file that will be executed for `django.setup()`. 
 
 In other words, if your `manage.py runserver` crashes, mypy will crash too. 
+You can also run `mypy` with [`--tb`](https://mypy.readthedocs.io/en/stable/command_line.html#cmdoption-mypy-show-traceback)
+option to get extra information about the error.
 
-This fully working [typed boilerplate](https://github.com/wemake-services/wemake-django-template) can serve you as an example.
+### I cannot use QuerySet or Manager with type annotations
 
+You can get a `TypeError: 'type' object is not subscriptable` 
+when you will try to use `QuerySet[MyModel]` or `Manager[MyModel]`.
 
-## Notes
+This happens because Django classes do not support [`__class_getitem__`](https://www.python.org/dev/peps/pep-0560/#class-getitem) magic method.
 
-Type implementation monkey-patches Django to add `__class_getitem__` to the `Manager` class. 
-If you would use Python3.7 and do that too in your code, you can make things like
+You can use strings instead: `'QuerySet[MyModel]'` and `'Manager[MyModel]'`, this way it will work as a type for `mypy` and as a regular `str` in runtime.
+
+Currently we [are working](https://github.com/django/django/pull/12405) on providing `__class_getitem__` to the classes where we need them.
+
+### How can I use HttpRequest with custom user model?
+
+You can subclass standard request like so:
 
 ```python
-class MyUserManager(models.Manager['MyUser']):
-    pass
+from django.http import HttpRequest
+from my_user_app.models import MyUser
 
-class MyUser(models.Model):
-    objects = MyUserManager()
+class MyRequest(HttpRequest):
+    user: MyUser
 ```
 
-work, which should make a error messages a bit better. 
+And then use `MyRequest` instead of standard `HttpRequest` inside your project.
+
+
+## Related projects
+
+- [`awesome-python-typing`](https://github.com/typeddjango/awesome-python-typing) - Awesome list of all typing-related things in Python.
+- [`djangorestframework-stubs`](https://github.com/typeddjango/djangorestframework-stubs) - Stubs for Django REST Framework.
+- [`pytest-mypy-plugins`](https://github.com/typeddjango/pytest-mypy-plugins) - `pytest` plugin that we use for testing `mypy` stubs and plugins.
+- [`wemake-django-template`](https://github.com/wemake-services/wemake-django-template) - Create new typed Django projects in seconds.
 
-Otherwise, custom type will be created in mypy, named `MyUser__MyUserManager`, which will rewrite base manager as `models.Manager[User]` to make methods like `get_queryset()` and others return properly typed `QuerySet`. 
 
 
 ## To get help
 
 We have Gitter here: <https://gitter.im/mypy-django/Lobby>
 
-If you think you have more generic typing issue, please refer to https://github.com/python/mypy and their Gitter.
+If you think you have more generic typing issue, please refer to <https://github.com/python/mypy> and their Gitter.

dev-requirements.txt

@@ -4,5 +4,5 @@ psycopg2
 flake8==3.7.9
 flake8-pyi==19.3.0
 isort==4.3.21
-gitpython==3.0.5
+gitpython==3.1.0
 -e .

django-stubs/conf/urls/__init__.pyi

@@ -5,10 +5,10 @@ from django.http.response import HttpResponse, HttpResponseBase
 
 from django.urls import URLResolver, URLPattern
 
-handler400: Callable[..., HttpResponse] = ...
-handler403: Callable[..., HttpResponse] = ...
-handler404: Callable[..., HttpResponse] = ...
-handler500: Callable[..., HttpResponse] = ...
+handler400: Union[str, Callable[..., HttpResponse]] = ...
+handler403: Union[str, Callable[..., HttpResponse]] = ...
+handler404: Union[str, Callable[..., HttpResponse]] = ...
+handler500: Union[str, Callable[..., HttpResponse]] = ...
 
 IncludedURLConf = Tuple[List[URLResolver], Optional[str], Optional[str]]
 

django-stubs/contrib/auth/decorators.pyi

@@ -1,13 +1,21 @@
-from typing import Callable, List, Optional, Set, Union
+from typing import Callable, List, Optional, Set, Union, TypeVar, overload
 
 from django.contrib.auth import REDIRECT_FIELD_NAME as REDIRECT_FIELD_NAME  # noqa: F401
+from django.http.response import HttpResponseBase
+
+from django.contrib.auth.models import AbstractUser
+
+_VIEW = TypeVar("_VIEW", bound=Callable[..., HttpResponseBase])
 
 def user_passes_test(
-    test_func: Callable, login_url: Optional[str] = ..., redirect_field_name: str = ...
-) -> Callable: ...
-def login_required(
-    function: Optional[Callable] = ..., redirect_field_name: str = ..., login_url: Optional[str] = ...
-) -> Callable: ...
+    test_func: Callable[[AbstractUser], bool], login_url: Optional[str] = ..., redirect_field_name: str = ...
+) -> Callable[[_VIEW], _VIEW]: ...
+
+# There are two ways of calling @login_required: @with(arguments) and @bare
+@overload
+def login_required(redirect_field_name: str = ..., login_url: Optional[str] = ...) -> Callable[[_VIEW], _VIEW]: ...
+@overload
+def login_required(function: _VIEW, redirect_field_name: str = ..., login_url: Optional[str] = ...) -> _VIEW: ...
 def permission_required(
     perm: Union[List[str], Set[str], str], login_url: None = ..., raise_exception: bool = ...
-) -> Callable: ...
+) -> Callable[[_VIEW], _VIEW]: ...

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

@@ -1,15 +1,14 @@
 from datetime import date, datetime as datetime
-from decimal import Decimal
-from typing import Any, Optional, Union
+from typing import Any, Optional, SupportsInt, Union
 
 register: Any
 
-def ordinal(value: Optional[str]) -> Optional[str]: ...
-def intcomma(value: Optional[Union[Decimal, float, str]], use_l10n: bool = ...) -> str: ...
+def ordinal(value: Optional[Union[str, SupportsInt]]) -> Optional[str]: ...
+def intcomma(value: Optional[Union[str, SupportsInt]], use_l10n: bool = ...) -> str: ...
 
 intword_converters: Any
 
-def intword(value: Optional[str]) -> Optional[Union[int, str]]: ...
-def apnumber(value: Optional[str]) -> Optional[Union[int, str]]: ...
+def intword(value: Optional[Union[str, SupportsInt]]) -> Optional[Union[int, str]]: ...
+def apnumber(value: Optional[Union[str, SupportsInt]]) -> Optional[Union[int, str]]: ...
 def naturalday(value: Optional[Union[date, str]], arg: None = ...) -> Optional[str]: ...
 def naturaltime(value: datetime) -> str: ...

django-stubs/core/checks/__init__.pyi

@@ -1,5 +1,17 @@
-from .messages import Warning as Warning, Info as Info, Debug as Debug, Error as Error, Critical as Critical
+from .messages import (
+    CheckMessage as CheckMessage,
+    Debug as Debug,
+    Info as Info,
+    Warning as Warning,
+    Error as Error,
+    Critical as Critical,
+    DEBUG as DEBUG,
+    INFO as INFO,
+    WARNING as WARNING,
+    ERROR as ERROR,
+    CRITICAL as CRITICAL,
+)
 
-from .registry import run_checks as run_checks, Tags as Tags, register as register
+from .registry import register as register, run_checks as run_checks, tag_exists as tag_exists, Tags as Tags
 
 from . import model_checks as model_checks

django-stubs/core/checks/messages.pyi

@@ -7,11 +7,11 @@ ERROR: int
 CRITICAL: int
 
 class CheckMessage:
-    level: Any = ...
-    msg: Any = ...
-    hint: Any = ...
+    level: int = ...
+    msg: str = ...
+    hint: Optional[str] = ...
     obj: Any = ...
-    id: Any = ...
+    id: Optional[str] = ...
     def __init__(
         self, level: int, msg: str, hint: Optional[str] = ..., obj: Any = ..., id: Optional[str] = ...
     ) -> None: ...
@@ -25,19 +25,9 @@ class Info(CheckMessage):
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Warning(CheckMessage):
-    hint: str
-    id: str
-    level: int
-    msg: str
-    obj: Any
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Error(CheckMessage):
-    hint: None
-    id: str
-    level: int
-    msg: str
-    obj: Any
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class Critical(CheckMessage):

django-stubs/core/files/base.pyi

@@ -8,7 +8,7 @@ _T = TypeVar("_T", bound="File")
 
 class File(FileProxyMixin, IO[Any]):
     DEFAULT_CHUNK_SIZE: Any = ...
-    file: StringIO = ...
+    file: IO[Any] = ...
     name: str = ...
     mode: str = ...
     def __init__(self, file: Any, name: Optional[str] = ...) -> None: ...

django-stubs/core/management/base.pyi

@@ -23,13 +23,16 @@ class OutputWrapper(TextIOBase):
     @property
     def style_func(self): ...
     @style_func.setter
-    def style_func(self, style_func: Any): ...
+    def style_func(self, style_func: Callable[[str], str]): ...
     ending: str = ...
     def __init__(
-        self, out: Union[StringIO, TextIOWrapper], style_func: Optional[Callable] = ..., ending: str = ...
+        self, out: Union[StringIO, TextIOWrapper], style_func: Optional[Callable[[str], str]] = ..., ending: str = ...
     ) -> None: ...
     def __getattr__(self, name: str) -> Callable: ...
     def isatty(self) -> bool: ...
+    def write(  # type: ignore[override]
+        self, msg: str, style_func: Optional[Callable[[str], str]] = ..., ending: Optional[str] = ...
+    ) -> None: ...
 
 class BaseCommand:
     help: str = ...

django-stubs/core/signing.pyi

@@ -21,7 +21,11 @@ def dumps(
     obj: Any, key: None = ..., salt: str = ..., serializer: Type[Serializer] = ..., compress: bool = ...
 ) -> str: ...
 def loads(
-    s: str, key: None = ..., salt: str = ..., serializer: Type[Serializer] = ..., max_age: Optional[int] = ...
+    s: str,
+    key: None = ...,
+    salt: str = ...,
+    serializer: Type[Serializer] = ...,
+    max_age: Optional[Union[int, timedelta]] = ...,
 ) -> Any: ...
 
 class Signer:

django-stubs/core/validators.pyi

@@ -1,6 +1,6 @@
 from decimal import Decimal
 from re import RegexFlag
-from typing import Any, Dict, List, Optional, Union, Pattern, Collection, Callable, Tuple
+from typing import Any, Callable, Collection, Dict, List, Optional, Pattern, Tuple, Union
 
 from django.core.files.base import File
 
@@ -13,7 +13,7 @@ def _lazy_re_compile(regex: _Regex, flags: int = ...): ...
 
 class RegexValidator:
     regex: _Regex = ...
-    message: Any = ...
+    message: str = ...
     code: str = ...
     inverse_match: bool = ...
     flags: int = ...
@@ -31,24 +31,24 @@ class URLValidator(RegexValidator):
     ul: str = ...
     ipv4_re: str = ...
     ipv6_re: str = ...
-    hostname_re: Any = ...
-    domain_re: Any = ...
-    tld_re: Any = ...
-    host_re: Any = ...
-    schemes: Any = ...
+    hostname_re: str = ...
+    domain_re: str = ...
+    tld_re: str = ...
+    host_re: str = ...
+    schemes: List[str] = ...
     def __init__(self, schemes: Optional[Collection[str]] = ..., **kwargs: Any) -> None: ...
 
-integer_validator: Any
+integer_validator: RegexValidator = ...
 
 def validate_integer(value: Optional[Union[float, str]]) -> None: ...
 
 class EmailValidator:
     message: str = ...
     code: str = ...
-    user_regex: Any = ...
-    domain_regex: Any = ...
-    literal_regex: Any = ...
-    domain_whitelist: Any = ...
+    user_regex: Pattern = ...
+    domain_regex: Pattern = ...
+    literal_regex: Pattern = ...
+    domain_whitelist: List[str] = ...
     def __init__(
         self,
         message: Optional[_ErrorMessage] = ...,
@@ -68,9 +68,10 @@ def validate_ipv4_address(value: str) -> None: ...
 def validate_ipv6_address(value: str) -> None: ...
 def validate_ipv46_address(value: str) -> None: ...
 
-ip_address_validator_map: Dict[str, Tuple[Callable[[Any], None], str]]
+_IPValidator = Tuple[Callable[[Any], None], str]
+ip_address_validator_map: Dict[str, _IPValidator]
 
-def ip_address_validators(protocol: str, unpack_ipv4: bool) -> Any: ...
+def ip_address_validators(protocol: str, unpack_ipv4: bool) -> _IPValidator: ...
 def int_list_validator(
     sep: str = ..., message: Optional[_ErrorMessage] = ..., code: str = ..., allow_negative: bool = ...
 ) -> RegexValidator: ...
@@ -92,7 +93,7 @@ class MinLengthValidator(BaseValidator): ...
 class MaxLengthValidator(BaseValidator): ...
 
 class DecimalValidator:
-    messages: Any = ...
+    messages: Dict[str, str] = ...
     max_digits: int = ...
     decimal_places: int = ...
     def __init__(self, max_digits: Optional[Union[int, str]], decimal_places: Optional[Union[int, str]]) -> None: ...

django-stubs/db/models/fields/__init__.pyi

@@ -108,7 +108,10 @@ class Field(RegisterLookupMixin, Generic[_ST, _GT]):
     def set_attributes_from_name(self, name: str) -> None: ...
     def db_type(self, connection: Any) -> str: ...
     def db_parameters(self, connection: Any) -> Dict[str, str]: ...
+    def pre_save(self, model_instance: Model, add: bool) -> Any: ...
     def get_prep_value(self, value: Any) -> Any: ...
+    def get_db_prep_value(self, value: Any, connection: Any, prepared: bool) -> Any: ...
+    def get_db_prep_save(self, value: Any, connection: Any) -> Any: ...
     def get_internal_type(self) -> str: ...
     # TODO: plugin support
     def formfield(self, **kwargs) -> Any: ...

django-stubs/db/models/manager.pyi

@@ -13,6 +13,7 @@ class BaseManager(QuerySet[_T]):
     name: str = ...
     model: Type[_T] = ...
     db: str
+    _db: Optional[str]
     def __init__(self) -> None: ...
     def deconstruct(self) -> Tuple[bool, str, None, Tuple, Dict[str, int]]: ...
     def check(self, **kwargs: Any) -> List[Any]: ...

django-stubs/db/transaction.pyi

@@ -39,4 +39,11 @@ def atomic(using: _C) -> _C: ...
 # Decorator or context-manager with parameters
 @overload
 def atomic(using: Optional[str] = ..., savepoint: bool = ...) -> Atomic: ...
-def non_atomic_requests(using: Callable = ...) -> Callable: ...
+
+# Bare decorator
+@overload
+def non_atomic_requests(using: _C) -> _C: ...
+
+# Decorator with arguments
+@overload
+def non_atomic_requests(using: Optional[str] = ...) -> Callable[[_C], _C]: ...

django-stubs/forms/fields.pyi

@@ -14,7 +14,7 @@ class Field:
     initial: Any
     label: Optional[str]
     required: bool
-    widget: Widget = ...
+    widget: Type[Widget] = ...
     hidden_widget: Any = ...
     default_validators: Any = ...
     default_error_messages: Any = ...

django-stubs/http/response.pyi

@@ -62,25 +62,27 @@ class HttpResponseBase(Iterable[Any]):
     def __iter__(self) -> Iterator[Any]: ...
 
 class HttpResponse(HttpResponseBase):
-    client: Client
-    context: Context
     content: Any
     csrf_cookie_set: bool
     redirect_chain: List[Tuple[str, int]]
-    request: Dict[str, Any]
-    resolver_match: ResolverMatch
     sameorigin: bool
-    templates: List[Template]
     test_server_port: str
     test_was_secure_request: bool
-    wsgi_request: WSGIRequest
     xframe_options_exempt: bool
     streaming: bool = ...
     def __init__(self, content: object = ..., *args: Any, **kwargs: Any) -> None: ...
     def serialize(self) -> bytes: ...
     @property
     def url(self) -> str: ...
-    def json(self) -> Dict[str, Any]: ...
+    # Attributes assigned by monkey-patching in test client ClientHandler.__call__()
+    wsgi_request: WSGIRequest
+    # Attributes assigned by monkey-patching in test client Client.request()
+    client: Client
+    request: Dict[str, Any]
+    templates: List[Template]
+    context: Context
+    resolver_match: ResolverMatch
+    def json(self) -> Any: ...
 
 class StreamingHttpResponse(HttpResponseBase):
     content: Any

django-stubs/test/client.pyi

@@ -1,15 +1,16 @@
 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.sessions.backends.base import SessionBase
 from django.core.handlers.base import BaseHandler
-from django.core.serializers.json import DjangoJSONEncoder
 from django.http.cookie import SimpleCookie
 from django.http.request import HttpRequest
 from django.http.response import HttpResponse, HttpResponseBase
 
 from django.core.handlers.wsgi import WSGIRequest
+from json import JSONEncoder
 
 BOUNDARY: str = ...
 MULTIPART_CONTENT: str = ...
@@ -37,11 +38,11 @@ def encode_multipart(boundary: str, data: Dict[str, Any]) -> bytes: ...
 def encode_file(boundary: str, key: str, file: Any) -> List[bytes]: ...
 
 class RequestFactory:
-    json_encoder: Type[DjangoJSONEncoder] = ...
-    defaults: Dict[str, str] = ...
-    cookies: SimpleCookie = ...
-    errors: BytesIO = ...
-    def __init__(self, *, json_encoder: Any = ..., **defaults: Any) -> None: ...
+    json_encoder: Type[JSONEncoder]
+    defaults: Dict[str, str]
+    cookies: SimpleCookie
+    errors: BytesIO
+    def __init__(self, *, json_encoder: Type[JSONEncoder] = ..., **defaults: Any) -> None: ...
     def request(self, **request: Any) -> WSGIRequest: ...
     def get(self, path: str, data: Any = ..., secure: bool = ..., **extra: Any) -> WSGIRequest: ...
     def post(
@@ -54,6 +55,7 @@ class RequestFactory:
         path: str,
         data: Union[Dict[str, str], str] = ...,
         content_type: str = ...,
+        follow: bool = ...,
         secure: bool = ...,
         **extra: Any
     ) -> WSGIRequest: ...
@@ -76,39 +78,50 @@ class RequestFactory:
         **extra: Any
     ) -> WSGIRequest: ...
 
-class Client:
-    json_encoder: Type[DjangoJSONEncoder] = ...
-    defaults: Dict[str, str] = ...
-    cookies: SimpleCookie = ...
-    errors: BytesIO = ...
-    handler: ClientHandler = ...
-    exc_info: None = ...
-    def __init__(self, enforce_csrf_checks: bool = ..., **defaults: Any) -> None: ...
-    def request(self, **request: Any) -> Any: ...
-    def get(self, path: str, data: Any = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def post(self, path: str, data: Any = ..., content_type: str = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def head(self, path: str, data: Any = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def trace(self, path: str, secure: bool = ..., **extra: Any) -> Any: ...
-    def options(
+class Client(RequestFactory):
+    handler: ClientHandler
+    raise_request_exception: bool
+    exc_info: Optional[Tuple[Type[BaseException], BaseException, TracebackType]]
+    def __init__(
+        self,
+        enforce_csrf_checks: bool = ...,
+        raise_request_exception: bool = ...,
+        *,
+        json_encoder: Type[JSONEncoder] = ...,
+        **defaults: Any
+    ) -> None: ...
+    # Silence type warnings, since this class overrides arguments and return types in an unsafe manner.
+    def request(self, **request: Any) -> HttpResponse: ...  # type: ignore
+    def get(  # type: ignore
+        self, path: str, data: Any = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def post(  # type: ignore
+        self, path: str, data: Any = ..., content_type: str = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def head(  # type: ignore
+        self, path: str, data: Any = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def trace(  # type: ignore
+        self, path: str, follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def options(  # type: ignore
         self,
         path: str,
         data: Union[Dict[str, str], str] = ...,
         content_type: str = ...,
+        follow: bool = ...,
         secure: bool = ...,
         **extra: Any
-    ) -> Any: ...
-    def put(self, path: str, data: Any = ..., content_type: str = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def patch(self, path: str, data: Any = ..., content_type: str = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def delete(self, path: str, data: Any = ..., content_type: str = ..., secure: bool = ..., **extra: Any) -> Any: ...
-    def generic(
-        self,
-        method: str,
-        path: str,
-        data: Any = ...,
-        content_type: Optional[str] = ...,
-        secure: bool = ...,
-        **extra: Any
-    ) -> Any: ...
+    ) -> HttpResponse: ...  # type: ignore
+    def put(  # type: ignore
+        self, path: str, data: Any = ..., content_type: str = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def patch(  # type: ignore
+        self, path: str, data: Any = ..., content_type: str = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
+    def delete(  # type: ignore
+        self, path: str, data: Any = ..., content_type: str = ..., follow: bool = ..., secure: bool = ..., **extra: Any
+    ) -> HttpResponse: ...  # type: ignore
     def store_exc_info(self, **kwargs: Any) -> None: ...
     @property
     def session(self) -> SessionBase: ...

django-stubs/test/utils.pyi

@@ -16,6 +16,7 @@ from typing import (
     Type,
     Union,
     ContextManager,
+    TypeVar,
 )
 
 from django.apps.registry import Apps
@@ -29,6 +30,7 @@ from django.conf import LazySettings, Settings
 
 _TestClass = Type[SimpleTestCase]
 _DecoratedTest = Union[Callable, _TestClass]
+_C = TypeVar("_C", bound=Callable)  # Any callable
 
 TZ_SUPPORT: bool = ...
 
@@ -56,7 +58,7 @@ class TestContextDecorator:
     def __enter__(self) -> Optional[Apps]: ...
     def __exit__(self, exc_type: None, exc_value: None, traceback: None) -> None: ...
     def decorate_class(self, cls: _TestClass) -> _TestClass: ...
-    def decorate_callable(self, func: Callable) -> Callable: ...
+    def decorate_callable(self, func: _C) -> _C: ...
     def __call__(self, decorated: _DecoratedTest) -> Any: ...
 
 class override_settings(TestContextDecorator):
@@ -146,7 +148,7 @@ def get_unique_databases_and_mirrors() -> Tuple[Dict[_Signature, _TestDatabase],
 def teardown_databases(
     old_config: Iterable[Tuple[Any, str, bool]], verbosity: int, parallel: int = ..., keepdb: bool = ...
 ) -> None: ...
-def require_jinja2(test_func: Callable) -> Callable: ...
+def require_jinja2(test_func: _C) -> _C: ...
 @contextmanager
 def register_lookup(
     field: Type[RegisterLookupMixin], *lookups: Type[Union[Lookup, Transform]], lookup_name: Optional[str] = ...

django-stubs/utils/cache.pyi

@@ -1,7 +1,6 @@
 from typing import Any, Optional, Tuple
 
 from django.core.cache.backends.base import BaseCache
-from django.core.cache.backends.locmem import LocMemCache
 from django.core.handlers.wsgi import WSGIRequest
 from django.http.response import HttpResponse, HttpResponseBase
 
@@ -28,5 +27,5 @@ def learn_cache_key(
     response: HttpResponse,
     cache_timeout: Optional[float] = ...,
     key_prefix: Optional[str] = ...,
-    cache: Optional[LocMemCache] = ...,
+    cache: Optional[BaseCache] = ...,
 ) -> str: ...

django-stubs/utils/decorators.pyi

@@ -1,13 +1,16 @@
-from typing import Any, Callable, Iterable, Optional, Type, Union
+from typing import Any, Callable, Iterable, Optional, Type, Union, TypeVar
 
 from django.utils.deprecation import MiddlewareMixin
+from django.views.generic.base import View
+
+_T = TypeVar("_T", bound=Union[View, Callable])  # Any callable
 
 class classonlymethod(classmethod): ...
 
-def method_decorator(decorator: Union[Callable, Iterable[Callable]], name: str = ...) -> Callable: ...
+def method_decorator(decorator: Union[Callable, Iterable[Callable]], name: str = ...) -> Callable[[_T], _T]: ...
 def decorator_from_middleware_with_args(middleware_class: type) -> Callable: ...
 def decorator_from_middleware(middleware_class: type) -> Callable: ...
-def available_attrs(fn: Any): ...
+def available_attrs(fn: Callable): ...
 def make_middleware_decorator(middleware_class: Type[MiddlewareMixin]) -> Callable: ...
 
 class classproperty:

django-stubs/utils/functional.pyi

@@ -1,16 +1,21 @@
-from typing import Any, Callable, Dict, List, Optional, Tuple, Type, Union
+from typing import Any, Callable, Dict, List, Optional, Tuple, Type, Union, TypeVar, Generic, overload
 from functools import wraps as wraps  # noqa: F401
 
 from django.db.models.base import Model
 
 def curry(_curried_func: Any, *args: Any, **kwargs: Any): ...
 
-class cached_property:
-    func: Callable = ...
+_T = TypeVar("_T")
+
+class cached_property(Generic[_T]):
+    func: Callable[..., _T] = ...
     __doc__: Any = ...
     name: str = ...
-    def __init__(self, func: Callable, name: Optional[str] = ...) -> None: ...
-    def __get__(self, instance: Any, cls: Type[Any] = ...) -> Any: ...
+    def __init__(self, func: Callable[..., _T], name: Optional[str] = ...): ...
+    @overload
+    def __get__(self, instance: None, cls: Type[Any] = ...) -> "cached_property[_T]": ...
+    @overload
+    def __get__(self, instance: object, cls: Type[Any] = ...) -> _T: ...
 
 class Promise: ...
 

mypy_django_plugin/lib/helpers.py

@@ -10,8 +10,8 @@ from mypy import checker
 from mypy.checker import TypeChecker
 from mypy.mro import calculate_mro
 from mypy.nodes import (
-    GDEF, MDEF, Argument, Block, ClassDef, Expression, FuncDef, MemberExpr, MypyFile, NameExpr, StrExpr, SymbolNode,
-    SymbolTable, SymbolTableNode, TypeInfo, Var,
+    GDEF, MDEF, Argument, Block, ClassDef, Expression, FuncDef, MemberExpr, MypyFile, NameExpr, PlaceholderNode,
+    StrExpr, SymbolNode, SymbolTable, SymbolTableNode, TypeInfo, Var,
 )
 from mypy.plugin import (
     AttributeContext, CheckerPluginInterface, ClassDefContext, DynamicClassDefContext, FunctionContext, MethodContext,
@@ -309,39 +309,67 @@ def add_new_sym_for_info(info: TypeInfo, *, name: str, sym_type: MypyType) -> No
                                        plugin_generated=True)
 
 
-def _prepare_new_method_arguments(node: FuncDef) -> Tuple[List[Argument], MypyType]:
-    arguments = []
-    for argument in node.arguments[1:]:
-        if argument.type_annotation is None:
+def build_unannotated_method_args(method_node: FuncDef) -> Tuple[List[Argument], MypyType]:
+    prepared_arguments = []
+    for argument in method_node.arguments[1:]:
         argument.type_annotation = AnyType(TypeOfAny.unannotated)
-        arguments.append(argument)
-
-    if isinstance(node.type, CallableType):
-        return_type = node.type.ret_type
-    else:
+        prepared_arguments.append(argument)
     return_type = AnyType(TypeOfAny.unannotated)
-
-    return arguments, return_type
+    return prepared_arguments, return_type
 
 
 def copy_method_to_another_class(ctx: ClassDefContext, self_type: Instance,
                                  new_method_name: str, method_node: FuncDef) -> None:
-    arguments, return_type = _prepare_new_method_arguments(method_node)
-
     semanal_api = get_semanal_api(ctx)
-    for argument in arguments:
-        if argument.type_annotation is not None:
-            argument.type_annotation = semanal_api.anal_type(argument.type_annotation,
-                                                             allow_placeholder=True)
-
-    if return_type is not None:
-        ret = semanal_api.anal_type(return_type,
-                                    allow_placeholder=True)
-        assert ret is not None
-        return_type = ret
+    if method_node.type is None:
+        if not semanal_api.final_iteration:
+            semanal_api.defer()
+            return
 
+        arguments, return_type = build_unannotated_method_args(method_node)
         add_method(ctx,
                    new_method_name,
                    args=arguments,
                    return_type=return_type,
                    self_type=self_type)
+        return
+
+    method_type = method_node.type
+    if not isinstance(method_type, CallableType):
+        if not semanal_api.final_iteration:
+            semanal_api.defer()
+        return
+
+    arguments = []
+    bound_return_type = semanal_api.anal_type(method_type.ret_type,
+                                              allow_placeholder=True)
+    assert bound_return_type is not None
+
+    if isinstance(bound_return_type, PlaceholderNode):
+        return
+
+    for arg_name, arg_type, original_argument in zip(method_type.arg_names[1:],
+                                                     method_type.arg_types[1:],
+                                                     method_node.arguments[1:]):
+        bound_arg_type = semanal_api.anal_type(arg_type, allow_placeholder=True)
+        assert bound_arg_type is not None
+
+        if isinstance(bound_arg_type, PlaceholderNode):
+            return
+
+        var = Var(name=original_argument.variable.name,
+                  type=arg_type)
+        var.line = original_argument.variable.line
+        var.column = original_argument.variable.column
+        argument = Argument(variable=var,
+                            type_annotation=bound_arg_type,
+                            initializer=original_argument.initializer,
+                            kind=original_argument.kind)
+        argument.set_line(original_argument)
+        arguments.append(argument)
+
+    add_method(ctx,
+               new_method_name,
+               args=arguments,
+               return_type=bound_return_type,
+               self_type=self_type)

scripts/enabled_test_modules.py

@@ -64,7 +64,12 @@ IGNORED_ERRORS = {
         'Incompatible types in string interpolation',
         '"None" has no attribute',
         'has no attribute "assert',
-        'Unsupported dynamic base class'
+        'Unsupported dynamic base class',
+        'error: "HttpResponse" has no attribute "streaming_content"',
+        'error: "HttpResponse" has no attribute "context_data"',
+    ],
+    'admin_inlines': [
+        'error: "HttpResponse" has no attribute "rendered_content"',
     ],
     'admin_utils': [
         '"Article" has no attribute "non_field"',
@@ -104,6 +109,7 @@ IGNORED_ERRORS = {
     ],
     'builtin_server': [
         '"ServerHandler" has no attribute',
+        'Incompatible types in assignment (expression has type "Tuple[BytesIO, BytesIO]"',
     ],
     'bulk_create': [
         'has incompatible type "List[Country]"; expected "Iterable[TwoFields]"',
@@ -164,7 +170,8 @@ IGNORED_ERRORS = {
         'Incompatible types in assignment (expression has type "Optional[Any]", variable has type "FloatModel")'
     ],
     'decorators': [
-        '"Type[object]" has no attribute "method"'
+        '"Type[object]" has no attribute "method"',
+        'Value of type variable "_T" of function cannot be "descriptor_wrapper"'
     ],
     'expressions_window': [
         'has incompatible type "str"'
@@ -191,7 +198,7 @@ IGNORED_ERRORS = {
     ],
     'from_db_value': [
         '"Cash" has no attribute',
-        'Argument 1 to "__str__" of "Decimal"',
+        '"__str__" of "Decimal"',
     ],
     'get_object_or_404': [
         'Argument 1 to "get_object_or_404" has incompatible type "str"; '
@@ -240,6 +247,7 @@ IGNORED_ERRORS = {
     ],
     'middleware': [
         re.compile(r'"(HttpRequest|WSGIRequest)" has no attribute'),
+        'Incompatible types in assignment (expression has type "HttpResponseBase", variable has type "HttpResponse")',
     ],
     'many_to_many': [
         '(expression has type "List[Article]", variable has type "Article_RelatedManager2',
@@ -276,6 +284,7 @@ IGNORED_ERRORS = {
         '"ImageFile" has no attribute "was_opened"',
         'Incompatible type for "size" of "FloatModel" (got "object", expected "Union[float, int, str, Combinable]")',
         'Incompatible type for "value" of "IntegerModel" (got "object", expected',
+        '"Child" has no attribute "get_foo_display"',
     ],
     'model_forms': [
         '"render" of "Widget"',
@@ -376,6 +385,9 @@ IGNORED_ERRORS = {
     'settings_tests': [
         'Argument 1 to "Settings" has incompatible type "Optional[str]"; expected "str"'
     ],
+    'shortcuts': [
+        'error: "Context" has no attribute "request"',
+    ],
     'signals': [
         'Argument 1 to "append" of "list" has incompatible type "Tuple[Any, Any, Optional[Any], Any]";'
     ],
@@ -387,7 +399,7 @@ IGNORED_ERRORS = {
         '"RequestSite" of "Union[Site, RequestSite]" has no attribute "id"',
     ],
     'syndication_tests': [
-        'List or tuple expected as variable arguments'
+        'Argument 1 to "add_domain" has incompatible type "*Tuple[object, ...]"',
     ],
     'sessions_tests': [
         'Incompatible types in assignment (expression has type "None", variable has type "int")',
@@ -428,6 +440,7 @@ IGNORED_ERRORS = {
     'test_client_regress': [
         '(expression has type "Dict[<nothing>, <nothing>]", variable has type "SessionBase")',
         'Unsupported left operand type for + ("None")',
+        'Argument 1 to "len" has incompatible type "Context"; expected "Sized"',
     ],
     'transactions': [
         'Incompatible types in assignment (expression has type "Thread", variable has type "Callable[[], Any]")'
@@ -457,7 +470,7 @@ IGNORED_ERRORS = {
         'No overload variant of "join" matches argument types "str", "None"',
         'Argument 1 to "Archive" has incompatible type "None"; expected "str"',
         'Argument 1 to "to_path" has incompatible type "int"; expected "Union[Path, str]"',
-
+        'Cannot infer type argument 1 of "cached_property"',
     ],
     'view_tests': [
         "Module 'django.views.debug' has no attribute 'Path'",

scripts/typecheck_tests.py

@@ -14,8 +14,8 @@ from scripts.enabled_test_modules import (
 )
 
 DJANGO_COMMIT_REFS: Dict[str, Tuple[str, str]] = {
-    '2.2': ('stable/2.2.x', '86befcc172c23170a720b3e0c06db51a99b3da59'),
-    '3.0': ('stable/3.0.x', '6cb30414bc0f83b49afc4cae76d4af5656effe9a')
+    '2.2': ('stable/2.2.x', '996be04c3ceb456754d9d527d4d708f30727f07e'),
+    '3.0': ('stable/3.0.x', 'd9f1792c7649e9f946f4a3a35a76bddf5a412b8b')
 }
 PROJECT_DIRECTORY = Path(__file__).parent.parent
 DJANGO_SOURCE_DIRECTORY = PROJECT_DIRECTORY / 'django-sources'  # type: Path

setup.py

@@ -21,14 +21,14 @@ with open('README.md', 'r') as f:
     readme = f.read()
 
 dependencies = [
-    'mypy>=0.760,<0.770',
+    'mypy>=0.770,<0.780',
     'typing-extensions',
     'django',
 ]
 
 setup(
     name="django-stubs",
-    version="1.4.0",
+    version="1.5.0",
     description='Mypy stubs for Django',
     long_description=readme,
     long_description_content_type='text/markdown',

test-data/typecheck/contrib/auth/test_decorators.yml

@@ -0,0 +1,43 @@
+-   case: login_required_bare
+    main: |
+        from django.contrib.auth.decorators import login_required
+        @login_required
+        def view_func(request): ...
+        reveal_type(view_func)  # N: Revealed type is 'def (request: Any) -> Any'
+-   case: login_required_fancy
+    main: |
+        from django.contrib.auth.decorators import login_required
+        from django.core.handlers.wsgi import WSGIRequest
+        from django.http import HttpResponse
+        @login_required(redirect_field_name='a', login_url='b')
+        def view_func(request: WSGIRequest, arg: str) -> HttpResponse: ...
+        reveal_type(view_func)  # N: Revealed type is 'def (request: django.core.handlers.wsgi.WSGIRequest, arg: builtins.str) -> django.http.response.HttpResponse'
+-   case: login_required_weird
+    main: |
+        from django.contrib.auth.decorators import login_required
+        # This is non-conventional usage, but covered in Django tests, so we allow it.
+        def view_func(request): ...
+        wrapped_view = login_required(view_func, redirect_field_name='a', login_url='b')
+        reveal_type(wrapped_view)  # N: Revealed type is 'def (request: Any) -> Any'
+-   case: login_required_incorrect_return
+    main: |
+        from django.contrib.auth.decorators import login_required
+        @login_required()  # E: Value of type variable "_VIEW" of function cannot be "Callable[[Any], str]"
+        def view_func2(request) -> str: ...
+-   case: user_passes_test
+    main: |
+        from django.contrib.auth.decorators import user_passes_test
+        @user_passes_test(lambda u: u.username.startswith('super'))
+        def view_func(request): ...
+        reveal_type(view_func)  # N: Revealed type is 'def (request: Any) -> Any'
+-   case: user_passes_test_bare_is_error
+    main: |
+        from django.http.response import HttpResponse
+        from django.contrib.auth.decorators import user_passes_test
+        @user_passes_test  # E: Argument 1 to "user_passes_test" has incompatible type "Callable[[Any], HttpResponse]"; expected "Callable[[AbstractUser], bool]"
+        def view_func(request) -> HttpResponse: ...
+-   case: permission_required
+    main: |
+        from django.contrib.auth.decorators import permission_required
+        @permission_required('polls.can_vote')
+        def view_func(request): ...

test-data/typecheck/db/test_transaction.yml

@@ -0,0 +1,28 @@
+-   case: atomic_bare
+    main: |
+      from django.db.transaction import atomic
+      @atomic
+      def func(x: int) -> list: ...
+      reveal_type(func)  # N: Revealed type is 'def (x: builtins.int) -> builtins.list[Any]'
+-   case: atomic_args
+    main: |
+      from django.db.transaction import atomic
+      @atomic(using='bla', savepoint=False)
+      def func(x: int) -> list: ...
+      reveal_type(func)  # N: Revealed type is 'def (x: builtins.int) -> builtins.list[Any]'
+-   case: non_atomic_requests_bare
+    main: |
+      from django.db.transaction import non_atomic_requests
+      @non_atomic_requests
+      def view_func(request): ...
+      reveal_type(view_func)  # N: Revealed type is 'def (request: Any) -> Any'
+
+-   case: non_atomic_requests_args
+    main: |
+      from django.http.request import HttpRequest
+      from django.http.response import HttpResponse
+      from django.db.transaction import non_atomic_requests
+      @non_atomic_requests
+      def view_func(request: HttpRequest, arg: str) -> HttpResponse: ...
+      reveal_type(view_func)  # N: Revealed type is 'def (request: django.http.request.HttpRequest, arg: builtins.str) -> django.http.response.HttpResponse'
+

test-data/typecheck/managers/querysets/test_from_queryset.yml

@@ -146,3 +146,36 @@
                         return param
 
                 NewManager = models.Manager.from_queryset(ModelQuerySet)
+
+-   case: from_queryset_with_inherited_manager_and_typing_no_return
+    disable_cache: true
+    main: |
+        from myapp.models import MyModel
+        reveal_type(MyModel().objects)  # N: Revealed type is 'myapp.models.MyModel_NewManager[myapp.models.MyModel]'
+        reveal_type(MyModel().objects.get())  # N: Revealed type is 'myapp.models.MyModel*'
+        reveal_type(MyModel().objects.base_queryset_method)  # N: Revealed type is 'def (param: Union[builtins.int, builtins.str]) -> <nothing>'
+        reveal_type(MyModel().objects.base_queryset_method(2))  # N: Revealed type is '<nothing>'
+    installed_apps:
+        - myapp
+    files:
+        -   path: myapp/__init__.py
+        -   path: myapp/models.py
+            content: |
+                from django.db import models
+                from myapp.managers import NewManager
+                class MyModel(models.Model):
+                    objects = NewManager()
+        -   path: myapp/managers.py
+            content: |
+                from django.db import models
+                from myapp.base_queryset import BaseQuerySet
+                class ModelQuerySet(BaseQuerySet):
+                    pass
+                NewManager = models.Manager.from_queryset(ModelQuerySet)
+        -   path: myapp/base_queryset.py
+            content: |
+                from typing import NoReturn, Union
+                from django.db import models
+                class BaseQuerySet(models.QuerySet):
+                    def base_queryset_method(self, param: Union[int, str]) -> NoReturn:
+                        raise ValueError

test-data/typecheck/managers/test_managers.yml

@@ -307,15 +307,15 @@
 -   case: custom_manager_returns_proper_model_types
     main: |
         from myapp.models import User
-        reveal_type(User.objects)  # N: Revealed type is 'myapp.models.User_MyManager[myapp.models.User]'
-        reveal_type(User.objects.select_related())  # N: Revealed type is 'myapp.models.User_MyManager[myapp.models.User]'
+        reveal_type(User.objects)  # N: Revealed type is 'myapp.models.User_MyManager2[myapp.models.User]'
+        reveal_type(User.objects.select_related())  # N: Revealed type is 'myapp.models.User_MyManager2[myapp.models.User]'
         reveal_type(User.objects.get())  # N: Revealed type is 'myapp.models.User*'
         reveal_type(User.objects.get_instance())  # N: Revealed type is 'builtins.int'
         reveal_type(User.objects.get_instance_untyped('hello'))  # N: Revealed type is 'Any'
 
         from myapp.models import ChildUser
-        reveal_type(ChildUser.objects)  # N: Revealed type is 'myapp.models.ChildUser_MyManager[myapp.models.ChildUser]'
-        reveal_type(ChildUser.objects.select_related())  # N: Revealed type is 'myapp.models.ChildUser_MyManager[myapp.models.ChildUser]'
+        reveal_type(ChildUser.objects)  # N: Revealed type is 'myapp.models.ChildUser_MyManager2[myapp.models.ChildUser]'
+        reveal_type(ChildUser.objects.select_related())  # N: Revealed type is 'myapp.models.ChildUser_MyManager2[myapp.models.ChildUser]'
         reveal_type(ChildUser.objects.get())  # N: Revealed type is 'myapp.models.ChildUser*'
         reveal_type(ChildUser.objects.get_instance())  # N: Revealed type is 'builtins.int'
         reveal_type(ChildUser.objects.get_instance_untyped('hello'))  # N: Revealed type is 'Any'

test-data/typecheck/test/test_testcase.yml

@@ -0,0 +1,12 @@
+-   case: testcase_client_attr
+    main: |
+      from django.test.testcases import TestCase
+
+      class ExampleTestCase(TestCase):
+          def test_method(self) -> None:
+              reveal_type(self.client)  # N: Revealed type is 'django.test.client.Client'
+              resp = self.client.post('/url', {'doit': 'srs'}, 'application/json', False, True, extra='value')
+              reveal_type(resp.status_code)   # N: Revealed type is 'builtins.int'
+              # Attributes monkey-patched by test Client class:
+              resp.json()
+              reveal_type(resp.wsgi_request)  # N: Revealed type is 'django.core.handlers.wsgi.WSGIRequest'

test-data/typecheck/utils/test_decorators.yml

@@ -0,0 +1,20 @@
+-   case: method_decorator_class
+    main: |
+      from django.views.generic.base import View
+      from django.utils.decorators import method_decorator
+      from django.contrib.auth.decorators import login_required
+      @method_decorator(login_required, name='dispatch')
+      class TestView(View): ...
+      reveal_type(TestView())  # N: Revealed type is 'main.TestView'
+-   case: method_decorator_function
+    main: |
+      from django.views.generic.base import View
+      from django.utils.decorators import method_decorator
+      from django.contrib.auth.decorators import login_required
+      from django.http.response import HttpResponse
+      from django.http.request import HttpRequest
+      class TestView(View):
+          @method_decorator(login_required)
+          def dispatch(self, request: HttpRequest, *args, **kwargs) -> HttpResponse:
+              return super().dispatch(request, *args, **kwargs)
+          reveal_type(dispatch)  # N: Revealed type is 'def (self: main.TestView, request: django.http.request.HttpRequest, *args: Any, **kwargs: Any) -> django.http.response.HttpResponse'

test-data/typecheck/utils/test_functional.yml

@@ -0,0 +1,18 @@
+-   case: cached_property_class_vs_instance_attributes
+    main: |
+      from django.utils.functional import cached_property
+      from typing import List
+
+      class Foo:
+          @cached_property
+          def attr(self) -> List[str]: ...
+
+          reveal_type(attr)      # N: Revealed type is 'django.utils.functional.cached_property[builtins.list*[builtins.str]]'
+          reveal_type(attr.name) # N: Revealed type is 'builtins.str'
+
+      reveal_type(Foo.attr)      # N: Revealed type is 'django.utils.functional.cached_property[builtins.list*[builtins.str]]'
+      reveal_type(Foo.attr.func) # N: Revealed type is 'def (*Any, **Any) -> builtins.list*[builtins.str]'
+
+      f = Foo()
+      reveal_type(f.attr)        # N: Revealed type is 'builtins.list*[builtins.str]'
+      f.attr.name                # E: "List[str]" has no attribute "name"