Add @type_check_only to stub-only private classes in stdlib (#14512)

stdlib/_compression.pyi

@@ -3,10 +3,11 @@
 from _typeshed import Incomplete, WriteableBuffer
 from collections.abc import Callable
 from io import DEFAULT_BUFFER_SIZE, BufferedIOBase, RawIOBase
-from typing import Any, Protocol
+from typing import Any, Protocol, type_check_only
 
 BUFFER_SIZE = DEFAULT_BUFFER_SIZE
 
+@type_check_only
 class _Reader(Protocol):
     def read(self, n: int, /) -> bytes: ...
     def seekable(self) -> bool: ...

stdlib/_ctypes.pyi

@@ -103,7 +103,10 @@ class _SimpleCData(_CData, Generic[_T], metaclass=_PyCSimpleType):
     def __init__(self, value: _T = ...) -> None: ...  # pyright: ignore[reportInvalidTypeVarUse]
     def __ctypes_from_outparam__(self, /) -> _T: ...  # type: ignore[override]
 
+@type_check_only
 class _CanCastTo(_CData): ...
+
+@type_check_only
 class _PointerLike(_CanCastTo): ...
 
 # This type is not exposed. It calls itself _ctypes.PyCPointerType.

stdlib/_gdbm.pyi

@@ -1,7 +1,7 @@
 import sys
 from _typeshed import ReadOnlyBuffer, StrOrBytesPath
 from types import TracebackType
-from typing import TypeVar, overload
+from typing import TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 if sys.platform != "win32":
@@ -13,6 +13,7 @@ if sys.platform != "win32":
 
     class error(OSError): ...
     # Actual typename gdbm, not exposed by the implementation
+    @type_check_only
     class _gdbm:
         def firstkey(self) -> bytes | None: ...
         def nextkey(self, key: _KeyType) -> bytes | None: ...

stdlib/_io.pyi

@@ -88,6 +88,7 @@ class BytesIO(BufferedIOBase, _BufferedIOBase, BinaryIO):  # type: ignore[misc]
     def readlines(self, size: int | None = None, /) -> list[bytes]: ...
     def seek(self, pos: int, whence: int = 0, /) -> int: ...
 
+@type_check_only
 class _BufferedReaderStream(Protocol):
     def read(self, n: int = ..., /) -> bytes: ...
     # Optional: def readall(self) -> bytes: ...

stdlib/_msi.pyi

@@ -1,8 +1,10 @@
 import sys
+from typing import type_check_only
 
 if sys.platform == "win32":
     class MSIError(Exception): ...
     # Actual typename View, not exposed by the implementation
+    @type_check_only
     class _View:
         def Execute(self, params: _Record | None = ...) -> None: ...
         def GetColumnInfo(self, kind: int) -> _Record: ...
@@ -14,6 +16,7 @@ if sys.platform == "win32":
         __init__: None  # type: ignore[assignment]
 
     # Actual typename SummaryInformation, not exposed by the implementation
+    @type_check_only
     class _SummaryInformation:
         def GetProperty(self, field: int) -> int | bytes | None: ...
         def GetPropertyCount(self) -> int: ...
@@ -24,6 +27,7 @@ if sys.platform == "win32":
         __init__: None  # type: ignore[assignment]
 
     # Actual typename Database, not exposed by the implementation
+    @type_check_only
     class _Database:
         def OpenView(self, sql: str) -> _View: ...
         def Commit(self) -> None: ...
@@ -34,6 +38,7 @@ if sys.platform == "win32":
         __init__: None  # type: ignore[assignment]
 
     # Actual typename Record, not exposed by the implementation
+    @type_check_only
     class _Record:
         def GetFieldCount(self) -> int: ...
         def GetInteger(self, field: int) -> int: ...

stdlib/_operator.pyi

@@ -28,6 +28,7 @@ class _SupportsDunderGT(Protocol):
 class _SupportsDunderLE(Protocol):
     def __le__(self, other: Any, /) -> Any: ...
 
+@type_check_only
 class _SupportsDunderGE(Protocol):
     def __ge__(self, other: Any, /) -> Any: ...
 

stdlib/_pickle.pyi

@@ -4,6 +4,7 @@ from pickle import PickleBuffer as PickleBuffer
 from typing import Any, Protocol, type_check_only
 from typing_extensions import TypeAlias
 
+@type_check_only
 class _ReadableFileobj(Protocol):
     def read(self, n: int, /) -> bytes: ...
     def readline(self) -> bytes: ...

stdlib/_ssl.pyi

@@ -12,7 +12,7 @@ from ssl import (
     SSLWantWriteError as SSLWantWriteError,
     SSLZeroReturnError as SSLZeroReturnError,
 )
-from typing import Any, ClassVar, Literal, TypedDict, final, overload
+from typing import Any, ClassVar, Literal, TypedDict, final, overload, type_check_only
 from typing_extensions import NotRequired, Self, TypeAlias
 
 _PasswordType: TypeAlias = Callable[[], str | bytes | bytearray] | str | bytes | bytearray
@@ -20,6 +20,7 @@ _PCTRTT: TypeAlias = tuple[tuple[str, str], ...]
 _PCTRTTT: TypeAlias = tuple[_PCTRTT, ...]
 _PeerCertRetDictType: TypeAlias = dict[str, str | _PCTRTTT | _PCTRTT]
 
+@type_check_only
 class _Cipher(TypedDict):
     aead: bool
     alg_bits: int
@@ -33,6 +34,7 @@ class _Cipher(TypedDict):
     strength_bits: int
     symmetric: str
 
+@type_check_only
 class _CertInfo(TypedDict):
     subject: tuple[tuple[tuple[str, str], ...], ...]
     issuer: tuple[tuple[tuple[str, str], ...], ...]

stdlib/ast.pyi

@@ -10,7 +10,7 @@ from _ast import (
 )
 from _typeshed import ReadableBuffer, Unused
 from collections.abc import Iterable, Iterator, Sequence
-from typing import Any, ClassVar, Generic, Literal, TypedDict, TypeVar as _TypeVar, overload
+from typing import Any, ClassVar, Generic, Literal, TypedDict, TypeVar as _TypeVar, overload, type_check_only
 from typing_extensions import Self, Unpack, deprecated
 
 if sys.version_info >= (3, 13):
@@ -20,6 +20,7 @@ if sys.version_info >= (3, 13):
 _EndPositionT = typing_extensions.TypeVar("_EndPositionT", int, int | None, default=int | None)
 
 # Corresponds to the names in the `_attributes` class variable which is non-empty in certain AST nodes
+@type_check_only
 class _Attributes(TypedDict, Generic[_EndPositionT], total=False):
     lineno: int
     col_offset: int
@@ -1698,8 +1699,14 @@ if sys.version_info >= (3, 12):
                 self, *, name: str = ..., default_value: expr | None = ..., **kwargs: Unpack[_Attributes[int]]
             ) -> Self: ...
 
-class _ABC(type):
-    def __init__(cls, *args: Unused) -> None: ...
+if sys.version_info >= (3, 14):
+    @type_check_only
+    class _ABC(type):
+        def __init__(cls, *args: Unused) -> None: ...
+
+else:
+    class _ABC(type):
+        def __init__(cls, *args: Unused) -> None: ...
 
 if sys.version_info < (3, 14):
     @deprecated("Replaced by ast.Constant; removed in Python 3.14")

stdlib/asyncio/events.pyi

@@ -12,7 +12,7 @@ from collections.abc import Callable, Sequence
 from concurrent.futures import Executor
 from contextvars import Context
 from socket import AddressFamily, SocketKind, _Address, _RetAddress, socket
-from typing import IO, Any, Literal, Protocol, TypeVar, overload
+from typing import IO, Any, Literal, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias, TypeVarTuple, Unpack, deprecated
 
 from . import _AwaitableLike, _CoroutineLike
@@ -68,6 +68,7 @@ _ExceptionHandler: TypeAlias = Callable[[AbstractEventLoop, _Context], object]
 _ProtocolFactory: TypeAlias = Callable[[], BaseProtocol]
 _SSLContext: TypeAlias = bool | None | ssl.SSLContext
 
+@type_check_only
 class _TaskFactory(Protocol):
     def __call__(self, loop: AbstractEventLoop, factory: _CoroutineLike[_T], /) -> Future[_T]: ...
 
@@ -599,6 +600,9 @@ class AbstractEventLoop:
     @abstractmethod
     async def shutdown_default_executor(self) -> None: ...
 
+# This class does not exist at runtime, but stubtest complains if it's marked as
+# @type_check_only because it has an alias that does exist at runtime. See mypy#19568.
+# @type_check_only
 class _AbstractEventLoopPolicy:
     @abstractmethod
     def get_event_loop(self) -> AbstractEventLoop: ...

stdlib/asyncio/format_helpers.pyi

@@ -3,9 +3,10 @@ import sys
 import traceback
 from collections.abc import Iterable
 from types import FrameType, FunctionType
-from typing import Any, overload
+from typing import Any, overload, type_check_only
 from typing_extensions import TypeAlias
 
+@type_check_only
 class _HasWrapper:
     __wrapper__: _HasWrapper | FunctionType
 

stdlib/asyncio/streams.pyi

@@ -3,7 +3,7 @@ import sys
 from _typeshed import ReadableBuffer, StrPath
 from collections.abc import Awaitable, Callable, Iterable, Sequence, Sized
 from types import ModuleType
-from typing import Any, Protocol, SupportsIndex
+from typing import Any, Protocol, SupportsIndex, type_check_only
 from typing_extensions import Self, TypeAlias
 
 from . import events, protocols, transports
@@ -25,6 +25,7 @@ else:
 
 _ClientConnectedCallback: TypeAlias = Callable[[StreamReader, StreamWriter], Awaitable[None] | None]
 
+@type_check_only
 class _ReaduntilBuffer(ReadableBuffer, Sized, Protocol): ...
 
 if sys.version_info >= (3, 10):

stdlib/asyncio/tasks.pyi

@@ -8,7 +8,7 @@ from _asyncio import (
     _unregister_task as _unregister_task,
 )
 from collections.abc import AsyncIterator, Awaitable, Coroutine, Generator, Iterable, Iterator
-from typing import Any, Literal, Protocol, TypeVar, overload
+from typing import Any, Literal, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import TypeAlias
 
 from . import _CoroutineLike
@@ -87,6 +87,7 @@ FIRST_EXCEPTION = concurrent.futures.FIRST_EXCEPTION
 ALL_COMPLETED = concurrent.futures.ALL_COMPLETED
 
 if sys.version_info >= (3, 13):
+    @type_check_only
     class _SyncAndAsyncIterator(Iterator[_T_co], AsyncIterator[_T_co], Protocol[_T_co]): ...
 
     def as_completed(fs: Iterable[_FutureLike[_T]], *, timeout: float | None = None) -> _SyncAndAsyncIterator[Future[_T]]: ...
@@ -445,6 +446,7 @@ elif sys.version_info >= (3, 12):
 if sys.version_info >= (3, 12):
     _TaskT_co = TypeVar("_TaskT_co", bound=Task[Any], covariant=True)
 
+    @type_check_only
     class _CustomTaskConstructor(Protocol[_TaskT_co]):
         def __call__(
             self,
@@ -457,6 +459,7 @@ if sys.version_info >= (3, 12):
             eager_start: bool,
         ) -> _TaskT_co: ...
 
+    @type_check_only
     class _EagerTaskFactoryType(Protocol[_TaskT_co]):
         def __call__(
             self,

stdlib/builtins.pyi

@@ -1340,6 +1340,9 @@ class property:
     def __set__(self, instance: Any, value: Any, /) -> None: ...
     def __delete__(self, instance: Any, /) -> None: ...
 
+# This class does not exist at runtime, but stubtest complains if it's marked as
+# @type_check_only because it has an alias that does exist at runtime. See mypy#19568.
+# @type_check_only
 @final
 class _NotImplementedType(Any):
     __call__: None
@@ -1513,7 +1516,7 @@ help: _sitebuiltins._Helper
 def hex(number: int | SupportsIndex, /) -> str: ...
 def id(obj: object, /) -> int: ...
 def input(prompt: object = "", /) -> str: ...
-
+@type_check_only
 class _GetItemIterable(Protocol[_T_co]):
     def __getitem__(self, i: int, /) -> _T_co: ...
 
@@ -1768,7 +1771,7 @@ def open(
     opener: _Opener | None = None,
 ) -> IO[Any]: ...
 def ord(c: str | bytes | bytearray, /) -> int: ...
-
+@type_check_only
 class _SupportsWriteAndFlush(SupportsWrite[_T_contra], SupportsFlush, Protocol[_T_contra]): ...
 
 @overload
@@ -1787,12 +1790,15 @@ def print(
 _E_contra = TypeVar("_E_contra", contravariant=True)
 _M_contra = TypeVar("_M_contra", contravariant=True)
 
+@type_check_only
 class _SupportsPow2(Protocol[_E_contra, _T_co]):
     def __pow__(self, other: _E_contra, /) -> _T_co: ...
 
+@type_check_only
 class _SupportsPow3NoneOnly(Protocol[_E_contra, _T_co]):
     def __pow__(self, other: _E_contra, modulo: None = None, /) -> _T_co: ...
 
+@type_check_only
 class _SupportsPow3(Protocol[_E_contra, _M_contra, _T_co]):
     def __pow__(self, other: _E_contra, modulo: _M_contra, /) -> _T_co: ...
 
@@ -1857,9 +1863,11 @@ def repr(obj: object, /) -> str: ...
 # and https://github.com/python/typeshed/pull/9151
 # on why we don't use `SupportsRound` from `typing.pyi`
 
+@type_check_only
 class _SupportsRound1(Protocol[_T_co]):
     def __round__(self) -> _T_co: ...
 
+@type_check_only
 class _SupportsRound2(Protocol[_T_co]):
     def __round__(self, ndigits: int, /) -> _T_co: ...
 
@@ -1881,6 +1889,7 @@ def sorted(iterable: Iterable[_T], /, *, key: Callable[[_T], SupportsRichCompari
 _AddableT1 = TypeVar("_AddableT1", bound=SupportsAdd[Any, Any])
 _AddableT2 = TypeVar("_AddableT2", bound=SupportsAdd[Any, Any])
 
+@type_check_only
 class _SupportsSumWithNoDefaultGiven(SupportsAdd[Any, Any], SupportsRAdd[int, Any], Protocol): ...
 
 _SupportsSumNoDefaultT = TypeVar("_SupportsSumNoDefaultT", bound=_SupportsSumWithNoDefaultGiven)

stdlib/bz2.pyi

@@ -3,7 +3,7 @@ from _bz2 import BZ2Compressor as BZ2Compressor, BZ2Decompressor as BZ2Decompres
 from _typeshed import ReadableBuffer, StrOrBytesPath, WriteableBuffer
 from collections.abc import Iterable
 from io import TextIOWrapper
-from typing import IO, Literal, Protocol, SupportsIndex, overload
+from typing import IO, Literal, Protocol, SupportsIndex, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 if sys.version_info >= (3, 14):
@@ -16,8 +16,10 @@ __all__ = ["BZ2File", "BZ2Compressor", "BZ2Decompressor", "open", "compress", "d
 # The following attributes and methods are optional:
 # def fileno(self) -> int: ...
 # def close(self) -> object: ...
+@type_check_only
 class _ReadableFileobj(_Reader, Protocol): ...
 
+@type_check_only
 class _WritableFileobj(Protocol):
     def write(self, b: bytes, /) -> object: ...
     # The following attributes and methods are optional:

stdlib/codecs.pyi

@@ -3,7 +3,7 @@ from _codecs import *
 from _typeshed import ReadableBuffer
 from abc import abstractmethod
 from collections.abc import Callable, Generator, Iterable
-from typing import Any, BinaryIO, ClassVar, Final, Literal, Protocol, TextIO, overload
+from typing import Any, BinaryIO, ClassVar, Final, Literal, Protocol, TextIO, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = [
@@ -73,16 +73,19 @@ _BufferedEncoding: TypeAlias = Literal[
     "utf-8-sig",
 ]
 
+@type_check_only
 class _WritableStream(Protocol):
     def write(self, data: bytes, /) -> object: ...
     def seek(self, offset: int, whence: int, /) -> object: ...
     def close(self) -> object: ...
 
+@type_check_only
 class _ReadableStream(Protocol):
     def read(self, size: int = ..., /) -> bytes: ...
     def seek(self, offset: int, whence: int, /) -> object: ...
     def close(self) -> object: ...
 
+@type_check_only
 class _Stream(_WritableStream, _ReadableStream, Protocol): ...
 
 # TODO: this only satisfies the most common interface, where
@@ -91,24 +94,31 @@ class _Stream(_WritableStream, _ReadableStream, Protocol): ...
 # There *are* bytes->bytes and str->str encodings in the standard library.
 # They were much more common in Python 2 than in Python 3.
 
+@type_check_only
 class _Encoder(Protocol):
     def __call__(self, input: str, errors: str = ..., /) -> tuple[bytes, int]: ...  # signature of Codec().encode
 
+@type_check_only
 class _Decoder(Protocol):
     def __call__(self, input: ReadableBuffer, errors: str = ..., /) -> tuple[str, int]: ...  # signature of Codec().decode
 
+@type_check_only
 class _StreamReader(Protocol):
     def __call__(self, stream: _ReadableStream, errors: str = ..., /) -> StreamReader: ...
 
+@type_check_only
 class _StreamWriter(Protocol):
     def __call__(self, stream: _WritableStream, errors: str = ..., /) -> StreamWriter: ...
 
+@type_check_only
 class _IncrementalEncoder(Protocol):
     def __call__(self, errors: str = ...) -> IncrementalEncoder: ...
 
+@type_check_only
 class _IncrementalDecoder(Protocol):
     def __call__(self, errors: str = ...) -> IncrementalDecoder: ...
 
+@type_check_only
 class _BufferedIncrementalDecoder(Protocol):
     def __call__(self, errors: str = ...) -> BufferedIncrementalDecoder: ...
 

stdlib/collections/__init__.pyi

@@ -2,7 +2,7 @@ import sys
 from _collections_abc import dict_items, dict_keys, dict_values
 from _typeshed import SupportsItems, SupportsKeysAndGetItem, SupportsRichComparison, SupportsRichComparisonT
 from types import GenericAlias
-from typing import Any, ClassVar, Generic, NoReturn, SupportsIndex, TypeVar, final, overload
+from typing import Any, ClassVar, Generic, NoReturn, SupportsIndex, TypeVar, final, overload, type_check_only
 from typing_extensions import Self
 
 if sys.version_info >= (3, 10):
@@ -342,14 +342,17 @@ class _OrderedDictValuesView(ValuesView[_VT_co]):
 # but they are not exposed anywhere)
 # pyright doesn't have a specific error code for subclassing error!
 @final
+@type_check_only
 class _odict_keys(dict_keys[_KT_co, _VT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
     def __reversed__(self) -> Iterator[_KT_co]: ...
 
 @final
+@type_check_only
 class _odict_items(dict_items[_KT_co, _VT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
     def __reversed__(self) -> Iterator[tuple[_KT_co, _VT_co]]: ...
 
 @final
+@type_check_only
 class _odict_values(dict_values[_KT_co, _VT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
     def __reversed__(self) -> Iterator[_VT_co]: ...
 

stdlib/concurrent/futures/_base.pyi

@@ -4,7 +4,7 @@ from _typeshed import Unused
 from collections.abc import Callable, Iterable, Iterator
 from logging import Logger
 from types import GenericAlias, TracebackType
-from typing import Any, Final, Generic, NamedTuple, Protocol, TypeVar
+from typing import Any, Final, Generic, NamedTuple, Protocol, TypeVar, type_check_only
 from typing_extensions import ParamSpec, Self
 
 FIRST_COMPLETED: Final = "FIRST_COMPLETED"
@@ -74,6 +74,7 @@ class Executor:
         self, exc_type: type[BaseException] | None, exc_val: BaseException | None, exc_tb: TracebackType | None
     ) -> bool | None: ...
 
+@type_check_only
 class _AsCompletedFuture(Protocol[_T_co]):
     # as_completed only mutates non-generic aspects of passed Futures and does not do any nominal
     # checks. Therefore, we can use a Protocol here to allow as_completed to act covariantly.

stdlib/configparser.pyi

@@ -2,7 +2,7 @@ import sys
 from _typeshed import MaybeNone, StrOrBytesPath, SupportsWrite
 from collections.abc import Callable, ItemsView, Iterable, Iterator, Mapping, MutableMapping, Sequence
 from re import Pattern
-from typing import Any, ClassVar, Final, Literal, TypeVar, overload
+from typing import Any, ClassVar, Final, Literal, TypeVar, overload, type_check_only
 from typing_extensions import TypeAlias
 
 if sys.version_info >= (3, 14):
@@ -104,7 +104,9 @@ else:
     ]
 
 if sys.version_info >= (3, 13):
+    @type_check_only
     class _UNNAMED_SECTION: ...
+
     UNNAMED_SECTION: _UNNAMED_SECTION
 
     _SectionName: TypeAlias = str | _UNNAMED_SECTION

stdlib/dataclasses.pyi

@@ -165,6 +165,7 @@ else:
     ) -> Callable[[type[_T]], type[_T]]: ...
 
 # See https://github.com/python/mypy/issues/10750
+@type_check_only
 class _DefaultFactory(Protocol[_T_co]):
     def __call__(self) -> _T_co: ...
 

stdlib/dbm/__init__.pyi

@@ -76,6 +76,7 @@ _TFlags: TypeAlias = Literal[
     "nusf",
 ]
 
+@type_check_only
 class _Database(MutableMapping[_KeyType, bytes]):
     def close(self) -> None: ...
     def __getitem__(self, key: _KeyType) -> bytes: ...

stdlib/email/headerregistry.pyi

@@ -13,7 +13,7 @@ from email._header_value_parser import (
 )
 from email.errors import MessageDefect
 from email.policy import Policy
-from typing import Any, ClassVar, Literal, Protocol
+from typing import Any, ClassVar, Literal, Protocol, type_check_only
 from typing_extensions import Self
 
 class BaseHeader(str):
@@ -137,6 +137,7 @@ class MessageIDHeader:
     @staticmethod
     def value_parser(value: str) -> MessageID: ...
 
+@type_check_only
 class _HeaderParser(Protocol):
     max_count: ClassVar[Literal[1] | None]
     @staticmethod

stdlib/email/message.pyi

@@ -5,7 +5,7 @@ from email.charset import Charset
 from email.contentmanager import ContentManager
 from email.errors import MessageDefect
 from email.policy import Policy
-from typing import Any, Generic, Literal, Protocol, TypeVar, overload
+from typing import Any, Generic, Literal, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = ["Message", "EmailMessage"]
@@ -24,9 +24,11 @@ _EncodedPayloadType: TypeAlias = Message | bytes
 _MultipartPayloadType: TypeAlias = list[_PayloadType]
 _CharsetType: TypeAlias = Charset | str | None
 
+@type_check_only
 class _SupportsEncodeToPayload(Protocol):
     def encode(self, encoding: str, /) -> _PayloadType | _MultipartPayloadType | _SupportsDecodeToPayload: ...
 
+@type_check_only
 class _SupportsDecodeToPayload(Protocol):
     def decode(self, encoding: str, errors: str, /) -> _PayloadType | _MultipartPayloadType: ...
 

stdlib/functools.pyi

@@ -3,7 +3,7 @@ import types
 from _typeshed import SupportsAllComparisons, SupportsItems
 from collections.abc import Callable, Hashable, Iterable, Sized
 from types import GenericAlias
-from typing import Any, Final, Generic, Literal, NamedTuple, TypedDict, TypeVar, final, overload
+from typing import Any, Final, Generic, Literal, NamedTuple, TypedDict, TypeVar, final, overload, type_check_only
 from typing_extensions import ParamSpec, Self, TypeAlias
 
 __all__ = [
@@ -48,6 +48,7 @@ class _CacheInfo(NamedTuple):
     maxsize: int | None
     currsize: int
 
+@type_check_only
 class _CacheParameters(TypedDict):
     maxsize: int
     typed: bool
@@ -96,6 +97,7 @@ else:
 
 WRAPPER_UPDATES: tuple[Literal["__dict__"]]
 
+@type_check_only
 class _Wrapped(Generic[_PWrapped, _RWrapped, _PWrapper, _RWrapper]):
     __wrapped__: Callable[_PWrapped, _RWrapped]
     def __call__(self, *args: _PWrapper.args, **kwargs: _PWrapper.kwargs) -> _RWrapper: ...
@@ -103,6 +105,7 @@ class _Wrapped(Generic[_PWrapped, _RWrapped, _PWrapper, _RWrapper]):
     __name__: str
     __qualname__: str
 
+@type_check_only
 class _Wrapper(Generic[_PWrapped, _RWrapped]):
     def __call__(self, f: Callable[_PWrapper, _RWrapper]) -> _Wrapped[_PWrapped, _RWrapped, _PWrapper, _RWrapper]: ...
 
@@ -180,6 +183,7 @@ if sys.version_info >= (3, 11):
 else:
     _RegType: TypeAlias = type[Any]
 
+@type_check_only
 class _SingleDispatchCallable(Generic[_T]):
     registry: types.MappingProxyType[Any, Callable[..., _T]]
     def dispatch(self, cls: Any) -> Callable[..., _T]: ...

stdlib/hashlib.pyi

@@ -20,7 +20,7 @@ from _hashlib import (
 )
 from _typeshed import ReadableBuffer
 from collections.abc import Callable, Set as AbstractSet
-from typing import Protocol
+from typing import Protocol, type_check_only
 
 if sys.version_info >= (3, 11):
     __all__ = (
@@ -72,9 +72,11 @@ algorithms_guaranteed: AbstractSet[str]
 algorithms_available: AbstractSet[str]
 
 if sys.version_info >= (3, 11):
+    @type_check_only
     class _BytesIOLike(Protocol):
         def getbuffer(self) -> ReadableBuffer: ...
 
+    @type_check_only
     class _FileDigestFileObj(Protocol):
         def readinto(self, buf: bytearray, /) -> int: ...
         def readable(self) -> bool: ...

stdlib/imp.pyi

@@ -13,7 +13,7 @@ from _imp import (
 from _typeshed import StrPath
 from os import PathLike
 from types import TracebackType
-from typing import IO, Any, Protocol
+from typing import IO, Any, Protocol, type_check_only
 
 SEARCH_ERROR: int
 PY_SOURCE: int
@@ -39,6 +39,7 @@ class NullImporter:
 
 # Technically, a text file has to support a slightly different set of operations than a binary file,
 # but we ignore that here.
+@type_check_only
 class _FileLike(Protocol):
     closed: bool
     mode: str

stdlib/logging/__init__.pyi

@@ -7,7 +7,7 @@ from re import Pattern
 from string import Template
 from time import struct_time
 from types import FrameType, GenericAlias, TracebackType
-from typing import Any, ClassVar, Final, Generic, Literal, Protocol, TextIO, TypeVar, overload
+from typing import Any, ClassVar, Final, Generic, Literal, Protocol, TextIO, TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias, deprecated
 
 __all__ = [
@@ -67,11 +67,13 @@ _Level: TypeAlias = int | str
 _FormatStyle: TypeAlias = Literal["%", "{", "$"]
 
 if sys.version_info >= (3, 12):
+    @type_check_only
     class _SupportsFilter(Protocol):
         def filter(self, record: LogRecord, /) -> bool | LogRecord: ...
 
     _FilterType: TypeAlias = Filter | Callable[[LogRecord], bool | LogRecord] | _SupportsFilter
 else:
+    @type_check_only
     class _SupportsFilter(Protocol):
         def filter(self, record: LogRecord, /) -> bool: ...
 

stdlib/logging/handlers.pyi

@@ -9,7 +9,7 @@ from re import Pattern
 from socket import SocketKind, socket
 from threading import Thread
 from types import TracebackType
-from typing import Any, ClassVar, Final, Protocol, TypeVar
+from typing import Any, ClassVar, Final, Protocol, TypeVar, type_check_only
 from typing_extensions import Self
 
 _T = TypeVar("_T")
@@ -225,6 +225,7 @@ class HTTPHandler(Handler):
     def mapLogRecord(self, record: LogRecord) -> dict[str, Any]: ...
     def getConnection(self, host: str, secure: bool) -> http.client.HTTPConnection: ...  # undocumented
 
+@type_check_only
 class _QueueLike(Protocol[_T]):
     def get(self) -> _T: ...
     def put_nowait(self, item: _T, /) -> None: ...

stdlib/mailbox.pyi

@@ -6,7 +6,7 @@ from abc import ABCMeta, abstractmethod
 from collections.abc import Callable, Iterable, Iterator, Mapping, Sequence
 from email._policybase import _MessageT
 from types import GenericAlias, TracebackType
-from typing import IO, Any, AnyStr, Generic, Literal, Protocol, TypeVar, overload
+from typing import IO, Any, AnyStr, Generic, Literal, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = [
@@ -31,13 +31,16 @@ __all__ = [
 
 _T = TypeVar("_T")
 
+@type_check_only
 class _SupportsReadAndReadline(SupportsRead[bytes], SupportsNoArgReadline[bytes], Protocol): ...
 
 _MessageData: TypeAlias = email.message.Message | bytes | str | io.StringIO | _SupportsReadAndReadline
 
+@type_check_only
 class _HasIteritems(Protocol):
     def iteritems(self) -> Iterator[tuple[str, _MessageData]]: ...
 
+@type_check_only
 class _HasItems(Protocol):
     def items(self) -> Iterator[tuple[str, _MessageData]]: ...
 

stdlib/multiprocessing/heap.pyi

@@ -2,7 +2,7 @@ import sys
 from _typeshed import Incomplete
 from collections.abc import Callable
 from mmap import mmap
-from typing import Protocol
+from typing import Protocol, type_check_only
 from typing_extensions import TypeAlias
 
 __all__ = ["BufferWrapper"]
@@ -20,6 +20,7 @@ class Arena:
 _Block: TypeAlias = tuple[Arena, int, int]
 
 if sys.platform != "win32":
+    @type_check_only
     class _SupportsDetach(Protocol):
         def detach(self) -> int: ...
 

stdlib/multiprocessing/sharedctypes.pyi

@@ -5,7 +5,7 @@ from ctypes import _SimpleCData, c_char
 from multiprocessing.context import BaseContext
 from multiprocessing.synchronize import _LockLike
 from types import TracebackType
-from typing import Any, Generic, Literal, Protocol, TypeVar, overload
+from typing import Any, Generic, Literal, Protocol, TypeVar, overload, type_check_only
 
 __all__ = ["RawValue", "RawArray", "Value", "Array", "copy", "synchronized"]
 
@@ -81,7 +81,7 @@ def synchronized(
 ) -> SynchronizedArray[_T]: ...
 @overload
 def synchronized(obj: _CT, lock: _LockLike | None = None, ctx: Any | None = None) -> SynchronizedBase[_CT]: ...
-
+@type_check_only
 class _AcquireFunc(Protocol):
     def __call__(self, block: bool = ..., timeout: float | None = ..., /) -> bool: ...
 

stdlib/numbers.pyi

@@ -8,7 +8,7 @@
 # nor `float` as a subtype of `numbers.Real`, etc.)
 
 from abc import ABCMeta, abstractmethod
-from typing import ClassVar, Literal, Protocol, overload
+from typing import ClassVar, Literal, Protocol, overload, type_check_only
 
 __all__ = ["Number", "Complex", "Real", "Rational", "Integral"]
 
@@ -22,6 +22,7 @@ __all__ = ["Number", "Complex", "Real", "Rational", "Integral"]
 # NOTE: We can't include `__complex__` here,
 # as we want `int` to be seen as a subtype of `_ComplexLike`,
 # and `int.__complex__` does not exist :(
+@type_check_only
 class _ComplexLike(Protocol):
     def __neg__(self) -> _ComplexLike: ...
     def __pos__(self) -> _ComplexLike: ...
@@ -29,6 +30,7 @@ class _ComplexLike(Protocol):
 
 # _RealLike is a structural-typing approximation
 # of the `Real` ABC, which is not (and cannot be) a protocol
+@type_check_only
 class _RealLike(_ComplexLike, Protocol):
     def __trunc__(self) -> _IntegralLike: ...
     def __floor__(self) -> _IntegralLike: ...
@@ -41,6 +43,7 @@ class _RealLike(_ComplexLike, Protocol):
 
 # _IntegralLike is a structural-typing approximation
 # of the `Integral` ABC, which is not (and cannot be) a protocol
+@type_check_only
 class _IntegralLike(_RealLike, Protocol):
     def __invert__(self) -> _IntegralLike: ...
     def __int__(self) -> int: ...

stdlib/os/__init__.pyi

@@ -39,6 +39,7 @@ from typing import (
     final,
     overload,
     runtime_checkable,
+    type_check_only,
 )
 from typing_extensions import Self, TypeAlias, Unpack, deprecated
 
@@ -1241,6 +1242,7 @@ def replace(
 ) -> None: ...
 def rmdir(path: StrOrBytesPath, *, dir_fd: int | None = None) -> None: ...
 @final
+@type_check_only
 class _ScandirIterator(Generic[AnyStr]):
     def __del__(self) -> None: ...
     def __iter__(self) -> Self: ...

stdlib/pydoc.pyi

@@ -5,7 +5,7 @@ from builtins import list as _list  # "list" conflicts with method name
 from collections.abc import Callable, Container, Mapping, MutableMapping
 from reprlib import Repr
 from types import MethodType, ModuleType, TracebackType
-from typing import IO, Any, AnyStr, Final, NoReturn, Protocol, TypeVar
+from typing import IO, Any, AnyStr, Final, NoReturn, Protocol, TypeVar, type_check_only
 from typing_extensions import TypeGuard, deprecated
 
 __all__ = ["help"]
@@ -17,6 +17,7 @@ __date__: Final[str]
 __version__: Final[str]
 __credits__: Final[str]
 
+@type_check_only
 class _Pager(Protocol):
     def __call__(self, text: str, title: str = "") -> None: ...
 

stdlib/quopri.pyi

@@ -1,8 +1,9 @@
 from _typeshed import ReadableBuffer, SupportsNoArgReadline, SupportsRead, SupportsWrite
-from typing import Protocol
+from typing import Protocol, type_check_only
 
 __all__ = ["encode", "decode", "encodestring", "decodestring"]
 
+@type_check_only
 class _Input(SupportsRead[bytes], SupportsNoArgReadline[bytes], Protocol): ...
 
 def encode(input: _Input, output: SupportsWrite[bytes], quotetabs: int, header: bool = False) -> None: ...

stdlib/shutil.pyi

@@ -3,7 +3,7 @@ import sys
 from _typeshed import BytesPath, ExcInfo, FileDescriptorOrPath, MaybeNone, StrOrBytesPath, StrPath, SupportsRead, SupportsWrite
 from collections.abc import Callable, Iterable, Sequence
 from tarfile import _TarfileFilter
-from typing import Any, AnyStr, NamedTuple, NoReturn, Protocol, TypeVar, overload
+from typing import Any, AnyStr, NamedTuple, NoReturn, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import TypeAlias, deprecated
 
 __all__ = [
@@ -79,6 +79,7 @@ def copytree(
 _OnErrorCallback: TypeAlias = Callable[[Callable[..., Any], str, ExcInfo], object]
 _OnExcCallback: TypeAlias = Callable[[Callable[..., Any], str, BaseException], object]
 
+@type_check_only
 class _RmtreeType(Protocol):
     avoids_symlink_attacks: bool
     if sys.version_info >= (3, 12):

stdlib/smtplib.pyi

@@ -7,7 +7,7 @@ from re import Pattern
 from socket import socket
 from ssl import SSLContext
 from types import TracebackType
-from typing import Any, Protocol, overload
+from typing import Any, Protocol, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = [
@@ -65,7 +65,7 @@ class SMTPAuthenticationError(SMTPResponseException): ...
 
 def quoteaddr(addrstring: str) -> str: ...
 def quotedata(data: str) -> str: ...
-
+@type_check_only
 class _AuthObject(Protocol):
     @overload
     def __call__(self, challenge: None = None, /) -> str | None: ...

stdlib/sqlite3/__init__.pyi

@@ -223,22 +223,26 @@ _Parameters: TypeAlias = SupportsLenAndGetItem[_AdaptedInputData] | Mapping[str,
 # Controls the legacy transaction handling mode of sqlite3.
 _IsolationLevel: TypeAlias = Literal["DEFERRED", "EXCLUSIVE", "IMMEDIATE"] | None
 
+@type_check_only
 class _AnyParamWindowAggregateClass(Protocol):
     def step(self, *args: Any) -> object: ...
     def inverse(self, *args: Any) -> object: ...
     def value(self) -> _SqliteData: ...
     def finalize(self) -> _SqliteData: ...
 
+@type_check_only
 class _WindowAggregateClass(Protocol):
     step: Callable[..., object]
     inverse: Callable[..., object]
     def value(self) -> _SqliteData: ...
     def finalize(self) -> _SqliteData: ...
 
+@type_check_only
 class _AggregateProtocol(Protocol):
     def step(self, value: int, /) -> object: ...
     def finalize(self) -> int: ...
 
+@type_check_only
 class _SingleParamWindowAggregateClass(Protocol):
     def step(self, param: Any, /) -> object: ...
     def inverse(self, param: Any, /) -> object: ...

stdlib/ssl.pyi

@@ -50,6 +50,7 @@ _SrvnmeCbType: TypeAlias = Callable[[SSLSocket | SSLObject, str | None, SSLSocke
 
 socket_error = OSError
 
+@type_check_only
 class _Cipher(TypedDict):
     aead: bool
     alg_bits: int

stdlib/sys/__init__.pyi

@@ -378,6 +378,7 @@ def settrace(function: TraceFunction | None, /) -> None: ...
 if sys.platform == "win32":
     # A tuple of length 5, even though it has more than 5 attributes.
     @final
+    @type_check_only
     class _WinVersion(_UninstantiableStructseq, tuple[int, int, int, int, str]):
         @property
         def major(self) -> int: ...

stdlib/time.pyi

@@ -1,6 +1,6 @@
 import sys
 from _typeshed import structseq
-from typing import Any, Final, Literal, Protocol, final
+from typing import Any, Final, Literal, Protocol, final, type_check_only
 from typing_extensions import TypeAlias
 
 _TimeTuple: TypeAlias = tuple[int, int, int, int, int, int, int, int, int]
@@ -80,6 +80,7 @@ def time() -> float: ...
 if sys.platform != "win32":
     def tzset() -> None: ...  # Unix only
 
+@type_check_only
 class _ClockInfo(Protocol):
     adjustable: bool
     implementation: str

stdlib/tkinter/__init__.pyi

@@ -366,12 +366,14 @@ def getboolean(s): ...
 
 _Ts = TypeVarTuple("_Ts")
 
+@type_check_only
 class _GridIndexInfo(TypedDict, total=False):
     minsize: _ScreenUnits
     pad: _ScreenUnits
     uniform: str | None
     weight: int
 
+@type_check_only
 class _BusyInfo(TypedDict):
     cursor: _Cursor
 
@@ -1039,6 +1041,7 @@ def Tcl(screenName: str | None = None, baseName: str | None = None, className: s
 _InMiscTotal = TypedDict("_InMiscTotal", {"in": Misc})
 _InMiscNonTotal = TypedDict("_InMiscNonTotal", {"in": Misc}, total=False)
 
+@type_check_only
 class _PackInfo(_InMiscTotal):
     # 'before' and 'after' never appear in _PackInfo
     anchor: _Anchor
@@ -1080,6 +1083,7 @@ class Pack:
     forget = pack_forget
     propagate = Misc.pack_propagate
 
+@type_check_only
 class _PlaceInfo(_InMiscNonTotal):  # empty dict if widget hasn't been placed
     anchor: _Anchor
     bordermode: Literal["inside", "outside", "ignore"]
@@ -1116,6 +1120,7 @@ class Place:
     place = place_configure
     info = place_info
 
+@type_check_only
 class _GridInfo(_InMiscNonTotal):  # empty dict if widget hasn't been gridded
     column: int
     columnspan: int

stdlib/tkinter/dnd.pyi

@@ -1,8 +1,9 @@
 from tkinter import Event, Misc, Tk, Widget
-from typing import ClassVar, Protocol
+from typing import ClassVar, Protocol, type_check_only
 
 __all__ = ["dnd_start", "DndHandler"]
 
+@type_check_only
 class _DndSource(Protocol):
     def dnd_end(self, target: Widget | None, event: Event[Misc] | None, /) -> None: ...
 

stdlib/tkinter/font.pyi

@@ -2,7 +2,7 @@ import _tkinter
 import itertools
 import sys
 import tkinter
-from typing import Any, ClassVar, Final, Literal, TypedDict, overload
+from typing import Any, ClassVar, Final, Literal, TypedDict, overload, type_check_only
 from typing_extensions import TypeAlias, Unpack
 
 __all__ = ["NORMAL", "ROMAN", "BOLD", "ITALIC", "nametofont", "Font", "families", "names"]
@@ -23,6 +23,7 @@ _FontDescription: TypeAlias = (
     | _tkinter.Tcl_Obj  # A font object constructed in Tcl
 )
 
+@type_check_only
 class _FontDict(TypedDict):
     family: str
     size: int
@@ -31,6 +32,7 @@ class _FontDict(TypedDict):
     underline: bool
     overstrike: bool
 
+@type_check_only
 class _MetricsDict(TypedDict):
     ascent: int
     descent: int

stdlib/tkinter/ttk.pyi

@@ -3,7 +3,7 @@ import tkinter
 from _typeshed import Incomplete, MaybeNone
 from collections.abc import Callable
 from tkinter.font import _FontDescription
-from typing import Any, Literal, TypedDict, overload
+from typing import Any, Literal, TypedDict, overload, type_check_only
 from typing_extensions import TypeAlias
 
 __all__ = [
@@ -928,6 +928,7 @@ class Spinbox(Entry):
     config = configure  # type: ignore[assignment]
     def set(self, value: Any) -> None: ...
 
+@type_check_only
 class _TreeviewItemDict(TypedDict):
     text: str
     image: list[str] | Literal[""]  # no idea why it's wrapped in list
@@ -935,6 +936,7 @@ class _TreeviewItemDict(TypedDict):
     open: bool  # actually 0 or 1
     tags: list[str] | Literal[""]
 
+@type_check_only
 class _TreeviewTagDict(TypedDict):
     # There is also 'text' and 'anchor', but they don't seem to do anything, using them is likely a bug
     foreground: str
@@ -942,6 +944,7 @@ class _TreeviewTagDict(TypedDict):
     font: _FontDescription
     image: str  # not wrapped in list :D
 
+@type_check_only
 class _TreeviewHeaderDict(TypedDict):
     text: str
     image: list[str] | Literal[""]
@@ -949,6 +952,7 @@ class _TreeviewHeaderDict(TypedDict):
     command: str
     state: str  # Doesn't seem to appear anywhere else than in these dicts
 
+@type_check_only
 class _TreeviewColumnDict(TypedDict):
     width: int
     minwidth: int

stdlib/turtle.pyi

@@ -3,7 +3,7 @@ from _typeshed import StrPath
 from collections.abc import Callable, Generator, Sequence
 from contextlib import contextmanager
 from tkinter import Canvas, Frame, Misc, PhotoImage, Scrollbar
-from typing import Any, ClassVar, Literal, TypedDict, overload
+from typing import Any, ClassVar, Literal, TypedDict, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = [
@@ -146,6 +146,7 @@ if sys.version_info < (3, 13):
 _Color: TypeAlias = str | tuple[float, float, float]
 _AnyColor: TypeAlias = Any
 
+@type_check_only
 class _PenState(TypedDict):
     shown: bool
     pendown: bool

stdlib/typing.pyi

@@ -419,6 +419,7 @@ def type_check_only(func_or_cls: _FT) -> _FT: ...
 
 # Type aliases and type constructors
 
+@type_check_only
 class _Alias:
     # Class for defining generic aliases for library types.
     def __getitem__(self, typeargs: Any) -> Any: ...
@@ -1125,6 +1126,7 @@ if sys.version_info >= (3, 13):
     def is_protocol(tp: type, /) -> bool: ...
     def get_protocol_members(tp: type, /) -> frozenset[str]: ...
     @final
+    @type_check_only
     class _NoDefaultType: ...
 
     NoDefault: _NoDefaultType

stdlib/typing_extensions.pyi

@@ -472,6 +472,7 @@ else:
     def is_protocol(tp: type, /) -> bool: ...
     def get_protocol_members(tp: type, /) -> frozenset[str]: ...
     @final
+    @type_check_only
     class _NoDefaultType: ...
 
     NoDefault: _NoDefaultType
@@ -603,6 +604,7 @@ class Doc:
     def __eq__(self, other: object) -> bool: ...
 
 # PEP 728
+@type_check_only
 class _NoExtraItemsType: ...
 
 NoExtraItems: _NoExtraItemsType

stdlib/unittest/case.pyi

@@ -7,7 +7,7 @@ from collections.abc import Callable, Container, Iterable, Mapping, Sequence, Se
 from contextlib import AbstractContextManager
 from re import Pattern
 from types import GenericAlias, TracebackType
-from typing import Any, AnyStr, Final, Generic, NoReturn, Protocol, SupportsAbs, SupportsRound, TypeVar, overload
+from typing import Any, AnyStr, Final, Generic, NoReturn, Protocol, SupportsAbs, SupportsRound, TypeVar, overload, type_check_only
 from typing_extensions import Never, ParamSpec, Self
 from unittest._log import _AssertLogsContext, _LoggingWatcher
 from warnings import WarningMessage
@@ -56,6 +56,7 @@ def skipUnless(condition: object, reason: str) -> Callable[[_FT], _FT]: ...
 class SkipTest(Exception):
     def __init__(self, reason: str) -> None: ...
 
+@type_check_only
 class _SupportsAbsAndDunderGE(SupportsDunderGE[Any], SupportsAbs[Any], Protocol): ...
 
 class TestCase:

stdlib/unittest/main.pyi

@@ -5,12 +5,13 @@ import unittest.result
 import unittest.suite
 from collections.abc import Iterable
 from types import ModuleType
-from typing import Any, Final, Protocol
+from typing import Any, Final, Protocol, type_check_only
 from typing_extensions import deprecated
 
 MAIN_EXAMPLES: Final[str]
 MODULE_EXAMPLES: Final[str]
 
+@type_check_only
 class _TestRunner(Protocol):
     def run(self, test: unittest.suite.TestSuite | unittest.case.TestCase, /) -> unittest.result.TestResult: ...
 

stdlib/unittest/mock.pyi

@@ -3,7 +3,7 @@ from _typeshed import MaybeNone
 from collections.abc import Awaitable, Callable, Coroutine, Iterable, Mapping, Sequence
 from contextlib import _GeneratorContextManager
 from types import TracebackType
-from typing import Any, ClassVar, Final, Generic, Literal, TypeVar, overload
+from typing import Any, ClassVar, Final, Generic, Literal, TypeVar, overload, type_check_only
 from typing_extensions import ParamSpec, Self, TypeAlias
 
 _T = TypeVar("_T")
@@ -262,6 +262,7 @@ class _patch(Generic[_T]):
 # This class does not exist at runtime, it's a hack to make this work:
 #     @patch("foo")
 #     def bar(..., mock: MagicMock) -> None: ...
+@type_check_only
 class _patch_pass_arg(_patch[_T]):
     @overload
     def __call__(self, func: _TT) -> _TT: ...
@@ -288,6 +289,7 @@ class _patch_dict:
 
 # This class does not exist at runtime, it's a hack to add methods to the
 # patch() function.
+@type_check_only
 class _patcher:
     TEST_PREFIX: str
     dict: type[_patch_dict]

stdlib/unittest/runner.pyi

@@ -4,15 +4,17 @@ import unittest.result
 import unittest.suite
 from _typeshed import SupportsFlush, SupportsWrite
 from collections.abc import Callable, Iterable
-from typing import Any, Generic, Protocol, TypeVar
+from typing import Any, Generic, Protocol, TypeVar, type_check_only
 from typing_extensions import Never, TypeAlias
 from warnings import _ActionKind
 
 _ResultClassType: TypeAlias = Callable[[_TextTestStream, bool, int], TextTestResult[Any]]
 
+@type_check_only
 class _SupportsWriteAndFlush(SupportsWrite[str], SupportsFlush, Protocol): ...
 
 # All methods used by unittest.runner.TextTestResult's stream
+@type_check_only
 class _TextTestStream(_SupportsWriteAndFlush, Protocol):
     def writeln(self, arg: str | None = None, /) -> None: ...
 

stdlib/urllib/request.pyi

@@ -6,7 +6,7 @@ from email.message import Message
 from http.client import HTTPConnection, HTTPMessage, HTTPResponse
 from http.cookiejar import CookieJar
 from re import Pattern
-from typing import IO, Any, ClassVar, NoReturn, Protocol, TypeVar, overload
+from typing import IO, Any, ClassVar, NoReturn, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import TypeAlias, deprecated
 from urllib.error import HTTPError as HTTPError
 from urllib.response import addclosehook, addinfourl
@@ -237,6 +237,7 @@ class ProxyDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler):
     auth_header: ClassVar[str]  # undocumented
     def http_error_407(self, req: Request, fp: IO[bytes], code: int, msg: str, headers: HTTPMessage) -> _UrlopenRet | None: ...
 
+@type_check_only
 class _HTTPConnectionProtocol(Protocol):
     def __call__(
         self,

stdlib/xml/dom/minidom.pyi

@@ -3,7 +3,7 @@ from _collections_abc import dict_keys, dict_values
 from _typeshed import Incomplete, ReadableBuffer, SupportsRead, SupportsWrite
 from collections.abc import Iterable, Sequence
 from types import TracebackType
-from typing import Any, ClassVar, Generic, Literal, NoReturn, Protocol, TypeVar, overload
+from typing import Any, ClassVar, Generic, Literal, NoReturn, Protocol, TypeVar, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 from xml.dom.minicompat import EmptyNodeList, NodeList
 from xml.dom.xmlbuilder import DocumentLS, DOMImplementationLS
@@ -40,9 +40,11 @@ _ImportableNodeVar = TypeVar(
     | Notation,
 )
 
+@type_check_only
 class _DOMErrorHandler(Protocol):
     def handleError(self, error: Exception) -> bool: ...
 
+@type_check_only
 class _UserDataHandler(Protocol):
     def handle(self, operation: int, key: str, data: Any, src: Node, dst: Node) -> None: ...
 

stdlib/xml/etree/ElementInclude.pyi

@@ -1,7 +1,8 @@
 from _typeshed import FileDescriptorOrPath
-from typing import Final, Literal, Protocol, overload
+from typing import Final, Literal, Protocol, overload, type_check_only
 from xml.etree.ElementTree import Element
 
+@type_check_only
 class _Loader(Protocol):
     @overload
     def __call__(self, href: FileDescriptorOrPath, parse: Literal["xml"], encoding: str | None = None) -> Element: ...

stdlib/xml/etree/ElementTree.pyi

@@ -335,6 +335,7 @@ class C14NWriterTarget:
 # The target type is tricky, because the implementation doesn't
 # require any particular attribute to be present. This documents the attributes
 # that can be present, but uncommenting any of them would require them.
+@type_check_only
 class _Target(Protocol):
     # start: Callable[str, dict[str, str], Any] | None
     # end: Callable[[str], Any] | None

stdlib/xml/sax/__init__.pyi

@@ -1,7 +1,7 @@
 import sys
 from _typeshed import ReadableBuffer, StrPath, SupportsRead, _T_co
 from collections.abc import Iterable
-from typing import Protocol
+from typing import Protocol, type_check_only
 from typing_extensions import TypeAlias
 from xml.sax._exceptions import (
     SAXException as SAXException,
@@ -13,6 +13,7 @@ from xml.sax._exceptions import (
 from xml.sax.handler import ContentHandler as ContentHandler, ErrorHandler as ErrorHandler
 from xml.sax.xmlreader import InputSource as InputSource, XMLReader
 
+@type_check_only
 class _SupportsReadClose(SupportsRead[_T_co], Protocol[_T_co]):
     def close(self) -> None: ...
 

stdlib/xmlrpc/client.pyi

@@ -6,9 +6,10 @@ from collections.abc import Callable, Iterable, Mapping
 from datetime import datetime
 from io import BytesIO
 from types import TracebackType
-from typing import Any, ClassVar, Final, Literal, Protocol, overload
+from typing import Any, ClassVar, Final, Literal, Protocol, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
+@type_check_only
 class _SupportsTimeTuple(Protocol):
     def timetuple(self) -> time.struct_time: ...
 

stdlib/xmlrpc/server.pyi

@@ -4,28 +4,34 @@ import socketserver
 from _typeshed import ReadableBuffer
 from collections.abc import Callable, Iterable, Mapping
 from re import Pattern
-from typing import Any, ClassVar, Protocol
+from typing import Any, ClassVar, Protocol, type_check_only
 from typing_extensions import TypeAlias
 from xmlrpc.client import Fault, _Marshallable
 
 # The dispatch accepts anywhere from 0 to N arguments, no easy way to allow this in mypy
+@type_check_only
 class _DispatchArity0(Protocol):
     def __call__(self) -> _Marshallable: ...
 
+@type_check_only
 class _DispatchArity1(Protocol):
     def __call__(self, arg1: _Marshallable, /) -> _Marshallable: ...
 
+@type_check_only
 class _DispatchArity2(Protocol):
     def __call__(self, arg1: _Marshallable, arg2: _Marshallable, /) -> _Marshallable: ...
 
+@type_check_only
 class _DispatchArity3(Protocol):
     def __call__(self, arg1: _Marshallable, arg2: _Marshallable, arg3: _Marshallable, /) -> _Marshallable: ...
 
+@type_check_only
 class _DispatchArity4(Protocol):
     def __call__(
         self, arg1: _Marshallable, arg2: _Marshallable, arg3: _Marshallable, arg4: _Marshallable, /
     ) -> _Marshallable: ...
 
+@type_check_only
 class _DispatchArityN(Protocol):
     def __call__(self, *args: _Marshallable) -> _Marshallable: ...
 

stdlib/zipfile/__init__.pyi

@@ -5,7 +5,7 @@ from collections.abc import Callable, Iterable, Iterator
 from io import TextIOWrapper
 from os import PathLike
 from types import TracebackType
-from typing import IO, Final, Literal, Protocol, overload
+from typing import IO, Final, Literal, Protocol, overload, type_check_only
 from typing_extensions import Self, TypeAlias
 
 __all__ = [
@@ -41,6 +41,7 @@ error = BadZipfile
 
 class LargeZipFile(Exception): ...
 
+@type_check_only
 class _ZipStream(Protocol):
     def read(self, n: int, /) -> bytes: ...
     # The following methods are optional:
@@ -49,11 +50,13 @@ class _ZipStream(Protocol):
     # def seek(self, n: int, /) -> object: ...
 
 # Stream shape as required by _EndRecData() and _EndRecData64().
+@type_check_only
 class _SupportsReadSeekTell(Protocol):
     def read(self, n: int = ..., /) -> bytes: ...
     def seek(self, cookie: int, whence: int, /) -> object: ...
     def tell(self) -> int: ...
 
+@type_check_only
 class _ClosableZipStream(_ZipStream, Protocol):
     def close(self) -> object: ...
 
@@ -93,18 +96,23 @@ class ZipExtFile(io.BufferedIOBase):
     def read1(self, n: int | None) -> bytes: ...  # type: ignore[override]
     def seek(self, offset: int, whence: int = 0) -> int: ...
 
+@type_check_only
 class _Writer(Protocol):
     def write(self, s: str, /) -> object: ...
 
+@type_check_only
 class _ZipReadable(Protocol):
     def seek(self, offset: int, whence: int = 0, /) -> int: ...
     def read(self, n: int = -1, /) -> bytes: ...
 
+@type_check_only
 class _ZipTellable(Protocol):
     def tell(self) -> int: ...
 
+@type_check_only
 class _ZipReadableTellable(_ZipReadable, _ZipTellable, Protocol): ...
 
+@type_check_only
 class _ZipWritable(Protocol):
     def flush(self) -> None: ...
     def close(self) -> None: ...

stdlib/zoneinfo/_common.pyi

@@ -1,6 +1,7 @@
 import io
-from typing import Any, Protocol
+from typing import Any, Protocol, type_check_only
 
+@type_check_only
 class _IOBytes(Protocol):
     def read(self, size: int, /) -> bytes: ...
     def seek(self, size: int, whence: int = ..., /) -> Any: ...