mark some positional-only arguments (#4693)

https://github.com/python/mypy/pull/9626 will make stubtest a little bit
stricter about positional-only arguments for dunders like __init__

Co-authored-by: hauntsaninja <>

stdlib/2and3/weakref.pyi

@@ -111,7 +111,7 @@ class WeakKeyDictionary(MutableMapping[_KT, _VT]):
 
 if sys.version_info >= (3, 4):
     class finalize:
-        def __init__(self, obj: _S, func: Callable[..., _T], *args: Any, **kwargs: Any) -> None: ...
+        def __init__(self, __obj: _S, __func: Callable[..., _T], *args: Any, **kwargs: Any) -> None: ...
         def __call__(self, _: Any = ...) -> Optional[_T]: ...
         def detach(self) -> Optional[Tuple[_S, _T, Tuple[Any, ...], Dict[str, Any]]]: ...
         def peek(self) -> Optional[Tuple[_S, _T, Tuple[Any, ...], Dict[str, Any]]]: ...

stdlib/3.7/_py_abc.pyi

@@ -6,5 +6,5 @@ _T = TypeVar("_T")
 def get_cache_token() -> object: ...
 
 class ABCMeta(type):
-    def __new__(cls, __name: str, __bases: Tuple[Type[Any], ...], __namespace: Dict[str, Any]) -> ABCMeta: ...
+    def __new__(__mcls, __name: str, __bases: Tuple[Type[Any], ...], __namespace: Dict[str, Any]) -> ABCMeta: ...
     def register(cls, subclass: Type[_T]) -> Type[_T]: ...

stdlib/3/collections/__init__.pyi

@@ -74,7 +74,7 @@ else:
 
 class UserDict(MutableMapping[_KT, _VT]):
     data: Dict[_KT, _VT]
-    def __init__(self, dict: Optional[Mapping[_KT, _VT]] = ..., **kwargs: _VT) -> None: ...
+    def __init__(self, __dict: Optional[Mapping[_KT, _VT]] = ..., **kwargs: _VT) -> None: ...
     def __len__(self) -> int: ...
     def __getitem__(self, key: _KT) -> _VT: ...
     def __setitem__(self, key: _KT, item: _VT) -> None: ...

stdlib/3/functools.pyi

@@ -77,9 +77,9 @@ class partialmethod(Generic[_T]):
     args: Tuple[Any, ...]
     keywords: Dict[str, Any]
     @overload
-    def __init__(self, func: Callable[..., _T], *args: Any, **keywords: Any) -> None: ...
+    def __init__(self, __func: Callable[..., _T], *args: Any, **keywords: Any) -> None: ...
     @overload
-    def __init__(self, func: _Descriptor, *args: Any, **keywords: Any) -> None: ...
+    def __init__(self, __func: _Descriptor, *args: Any, **keywords: Any) -> None: ...
     def __get__(self, obj: Any, cls: Type[Any]) -> Callable[..., _T]: ...
     @property
     def __isabstractmethod__(self) -> bool: ...

stdlib/3/unittest/mock.pyi

@@ -73,7 +73,7 @@ class Base:
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class NonCallableMock(Base, Any):  # type: ignore
-    def __new__(cls, *args: Any, **kw: Any) -> NonCallableMock: ...
+    def __new__(__cls, *args: Any, **kw: Any) -> NonCallableMock: ...
     def __init__(
         self,
         spec: Union[List[str], object, Type[object], None] = ...,

third_party/2and3/mock.pyi

@@ -73,7 +73,7 @@ class Base:
     def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class NonCallableMock(Base, Any):  # type: ignore
-    def __new__(cls, *args: Any, **kw: Any) -> NonCallableMock: ...
+    def __new__(__cls, *args: Any, **kw: Any) -> NonCallableMock: ...
     def __init__(
         self,
         spec: Union[List[str], object, Type[object], None] = ...,