move some stuffs related to _SimpleCData from ctypes/__init__.pyi to _ctypes.pyi, as at runtime.

stdlib/_ctypes.pyi

@@ -1,6 +1,16 @@
 import sys
-from ctypes import _CArgObject, _PointerLike
-from typing_extensions import TypeAlias
+from _typeshed import ReadableBuffer, WriteableBuffer
+from abc import abstractmethod
+from collections.abc import Iterable, Iterator, Mapping
+from ctypes import CDLL, _CArgObject, _PointerLike
+from typing import Any, Generic, TypeVar, overload
+from typing_extensions import Self, TypeAlias
+
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
+_T = TypeVar("_T")
+_CT = TypeVar("_CT", bound=_CData)
 
 FUNCFLAG_CDECL: int
 FUNCFLAG_PYTHONAPI: int
@@ -27,3 +37,76 @@ if sys.platform == "win32":
 
     FUNCFLAG_HRESULT: int
     FUNCFLAG_STDCALL: int
+
+class _CDataMeta(type):
+    # By default mypy complains about the following two methods, because strictly speaking cls
+    # might not be a Type[_CT]. However this can never actually happen, because the only class that
+    # uses _CDataMeta as its metaclass is _CData. So it's safe to ignore the errors here.
+    def __mul__(cls: type[_CT], other: int) -> type[Array[_CT]]: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
+    def __rmul__(cls: type[_CT], other: int) -> type[Array[_CT]]: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
+
+class _CData(metaclass=_CDataMeta):
+    _b_base_: int
+    _b_needsfree_: bool
+    _objects: Mapping[Any, int] | None
+    @classmethod
+    def from_buffer(cls, source: WriteableBuffer, offset: int = ...) -> Self: ...
+    @classmethod
+    def from_buffer_copy(cls, source: ReadableBuffer, offset: int = ...) -> Self: ...
+    @classmethod
+    def from_address(cls, address: int) -> Self: ...
+    @classmethod
+    def from_param(cls, obj: Any) -> Self | _CArgObject: ...
+    @classmethod
+    def in_dll(cls, library: CDLL, name: str) -> Self: ...
+
+class _SimpleCData(Generic[_T], _CData):
+    value: _T
+    # The TypeVar can be unsolved here,
+    # but we can't use overloads without creating many, many mypy false-positive errors
+    def __init__(self, value: _T = ...) -> None: ...  # pyright: ignore[reportInvalidTypeVarUse]
+
+class Array(Generic[_CT], _CData):
+    @property
+    @abstractmethod
+    def _length_(self) -> int: ...
+    @_length_.setter
+    def _length_(self, value: int) -> None: ...
+    @property
+    @abstractmethod
+    def _type_(self) -> type[_CT]: ...
+    @_type_.setter
+    def _type_(self, value: type[_CT]) -> None: ...
+    # Note: only available if _CT == c_char
+    @property
+    def raw(self) -> bytes: ...
+    @raw.setter
+    def raw(self, value: ReadableBuffer) -> None: ...
+    value: Any  # Note: bytes if _CT == c_char, str if _CT == c_wchar, unavailable otherwise
+    # TODO These methods cannot be annotated correctly at the moment.
+    # All of these "Any"s stand for the array's element type, but it's not possible to use _CT
+    # here, because of a special feature of ctypes.
+    # By default, when accessing an element of an Array[_CT], the returned object has type _CT.
+    # However, when _CT is a "simple type" like c_int, ctypes automatically "unboxes" the object
+    # and converts it to the corresponding Python primitive. For example, when accessing an element
+    # of an Array[c_int], a Python int object is returned, not a c_int.
+    # This behavior does *not* apply to subclasses of "simple types".
+    # If MyInt is a subclass of c_int, then accessing an element of an Array[MyInt] returns
+    # a MyInt, not an int.
+    # This special behavior is not easy to model in a stub, so for now all places where
+    # the array element type would belong are annotated with Any instead.
+    def __init__(self, *args: Any) -> None: ...
+    @overload
+    def __getitem__(self, __key: int) -> Any: ...
+    @overload
+    def __getitem__(self, __key: slice) -> list[Any]: ...
+    @overload
+    def __setitem__(self, __key: int, __value: Any) -> None: ...
+    @overload
+    def __setitem__(self, __key: slice, __value: Iterable[Any]) -> None: ...
+    def __iter__(self) -> Iterator[Any]: ...
+    # Can't inherit from Sized because the metaclass conflict between
+    # Sized and _CData prevents using _CDataMeta.
+    def __len__(self) -> int: ...
+    if sys.version_info >= (3, 9):
+        def __class_getitem__(cls, item: Any) -> GenericAlias: ...

stdlib/ctypes/__init__.pyi

@@ -1,10 +1,15 @@
 import sys
-from _ctypes import RTLD_GLOBAL as RTLD_GLOBAL, RTLD_LOCAL as RTLD_LOCAL
-from _typeshed import ReadableBuffer, WriteableBuffer
-from abc import abstractmethod
-from collections.abc import Callable, Iterable, Iterator, Mapping, Sequence
+from _ctypes import (
+    RTLD_GLOBAL as RTLD_GLOBAL,
+    RTLD_LOCAL as RTLD_LOCAL,
+    Array as Array,
+    _CData as _CData,
+    _CDataMeta as _CDataMeta,
+    _SimpleCData as _SimpleCData,
+)
+from collections.abc import Callable, Sequence
 from typing import Any, ClassVar, Generic, TypeVar, overload
-from typing_extensions import Self, TypeAlias
+from typing_extensions import TypeAlias
 
 if sys.version_info >= (3, 9):
     from types import GenericAlias
@@ -65,28 +70,6 @@ if sys.platform == "win32":
 pydll: LibraryLoader[PyDLL]
 pythonapi: PyDLL
 
-class _CDataMeta(type):
-    # By default mypy complains about the following two methods, because strictly speaking cls
-    # might not be a Type[_CT]. However this can never actually happen, because the only class that
-    # uses _CDataMeta as its metaclass is _CData. So it's safe to ignore the errors here.
-    def __mul__(cls: type[_CT], other: int) -> type[Array[_CT]]: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
-    def __rmul__(cls: type[_CT], other: int) -> type[Array[_CT]]: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
-
-class _CData(metaclass=_CDataMeta):
-    _b_base_: int
-    _b_needsfree_: bool
-    _objects: Mapping[Any, int] | None
-    @classmethod
-    def from_buffer(cls, source: WriteableBuffer, offset: int = ...) -> Self: ...
-    @classmethod
-    def from_buffer_copy(cls, source: ReadableBuffer, offset: int = ...) -> Self: ...
-    @classmethod
-    def from_address(cls, address: int) -> Self: ...
-    @classmethod
-    def from_param(cls, obj: Any) -> Self | _CArgObject: ...
-    @classmethod
-    def in_dll(cls, library: CDLL, name: str) -> Self: ...
-
 class _CanCastTo(_CData): ...
 class _PointerLike(_CanCastTo): ...
 
@@ -190,12 +173,6 @@ if sys.platform == "win32":
 
 def wstring_at(address: _CVoidConstPLike, size: int = -1) -> str: ...
 
-class _SimpleCData(Generic[_T], _CData):
-    value: _T
-    # The TypeVar can be unsolved here,
-    # but we can't use overloads without creating many, many mypy false-positive errors
-    def __init__(self, value: _T = ...) -> None: ...  # pyright: ignore[reportInvalidTypeVarUse]
-
 class c_byte(_SimpleCData[int]): ...
 
 class c_char(_SimpleCData[bytes]):
@@ -259,48 +236,3 @@ class Union(_StructUnionBase): ...
 class Structure(_StructUnionBase): ...
 class BigEndianStructure(Structure): ...
 class LittleEndianStructure(Structure): ...
-
-class Array(Generic[_CT], _CData):
-    @property
-    @abstractmethod
-    def _length_(self) -> int: ...
-    @_length_.setter
-    def _length_(self, value: int) -> None: ...
-    @property
-    @abstractmethod
-    def _type_(self) -> type[_CT]: ...
-    @_type_.setter
-    def _type_(self, value: type[_CT]) -> None: ...
-    # Note: only available if _CT == c_char
-    @property
-    def raw(self) -> bytes: ...
-    @raw.setter
-    def raw(self, value: ReadableBuffer) -> None: ...
-    value: Any  # Note: bytes if _CT == c_char, str if _CT == c_wchar, unavailable otherwise
-    # TODO These methods cannot be annotated correctly at the moment.
-    # All of these "Any"s stand for the array's element type, but it's not possible to use _CT
-    # here, because of a special feature of ctypes.
-    # By default, when accessing an element of an Array[_CT], the returned object has type _CT.
-    # However, when _CT is a "simple type" like c_int, ctypes automatically "unboxes" the object
-    # and converts it to the corresponding Python primitive. For example, when accessing an element
-    # of an Array[c_int], a Python int object is returned, not a c_int.
-    # This behavior does *not* apply to subclasses of "simple types".
-    # If MyInt is a subclass of c_int, then accessing an element of an Array[MyInt] returns
-    # a MyInt, not an int.
-    # This special behavior is not easy to model in a stub, so for now all places where
-    # the array element type would belong are annotated with Any instead.
-    def __init__(self, *args: Any) -> None: ...
-    @overload
-    def __getitem__(self, __key: int) -> Any: ...
-    @overload
-    def __getitem__(self, __key: slice) -> list[Any]: ...
-    @overload
-    def __setitem__(self, __key: int, __value: Any) -> None: ...
-    @overload
-    def __setitem__(self, __key: slice, __value: Iterable[Any]) -> None: ...
-    def __iter__(self) -> Iterator[Any]: ...
-    # Can't inherit from Sized because the metaclass conflict between
-    # Sized and _CData prevents using _CDataMeta.
-    def __len__(self) -> int: ...
-    if sys.version_info >= (3, 9):
-        def __class_getitem__(cls, item: Any) -> GenericAlias: ...

tests/stubtest_allowlists/py3_common.txt

@@ -78,7 +78,9 @@ csv.Dialect.skipinitialspace
 csv.DictReader.__init__  # runtime sig has *args but will error if more than 5 positional args are supplied
 csv.DictWriter.__init__  # runtime sig has *args but will error if more than 5 positional args are supplied
 ctypes.Array._type_  # _type_ and _length_ are abstract, https://github.com/python/typeshed/pull/6361
+_ctypes.Array._type_
 ctypes.Array._length_
+_ctypes.Array._length_
 ctypes.CDLL._FuncPtr  # None at class level but initialized in __init__ to this value
 ctypes.memmove  # CFunctionType
 ctypes.memset  # CFunctionType
@@ -332,7 +334,6 @@ turtle.ScrolledCanvas.onResize
 wave.Wave_read.initfp
 wave.Wave_write.initfp
 
-_ctypes.Array
 _ctypes.CFuncPtr
 _ctypes.POINTER
 _ctypes.PyObj_FromPtr
@@ -357,6 +358,7 @@ _ctypes.sizeof
 # ==========
 
 ctypes.Array.raw  # exists but stubtest can't see it; only available if _CT == c_char
+_ctypes.Array.raw
 
 _collections_abc.AsyncGenerator.asend  # async at runtime, deliberately not in the stub, see #7491. Pos-only differences also.
 _collections_abc.AsyncGenerator.__anext__  # async at runtime, deliberately not in the stub, see #7491
@@ -605,6 +607,7 @@ wsgiref.handlers.BaseHandler.status
 
 # Iterable classes that don't define __iter__ at runtime (usually iterable via __getitem__)
 # These would ideally be special-cased by type checkers; see https://github.com/python/mypy/issues/2220
+_ctypes.Array.__iter__
 ctypes.Array.__iter__
 mmap.mmap.__iter__
 mmap.mmap.__contains__