Use _typeshed.Self with __enter__ (#5717)

Co-authored-by: Akuli <akuviljanen17@gmail.com>

stdlib/io.pyi

@@ -1,9 +1,9 @@
 import builtins
 import codecs
 import sys
-from _typeshed import ReadableBuffer, WriteableBuffer
+from _typeshed import ReadableBuffer, Self, WriteableBuffer
 from types import TracebackType
-from typing import IO, Any, BinaryIO, Callable, Iterable, Iterator, List, Optional, TextIO, Tuple, Type, TypeVar, Union
+from typing import IO, Any, BinaryIO, Callable, Iterable, Iterator, List, Optional, TextIO, Tuple, Type, Union
 
 DEFAULT_BUFFER_SIZE: int
 
@@ -11,8 +11,6 @@ SEEK_SET: int
 SEEK_CUR: int
 SEEK_END: int
 
-_T = TypeVar("_T", bound=IOBase)
-
 open = builtins.open
 
 if sys.version_info >= (3, 8):
@@ -25,7 +23,7 @@ class UnsupportedOperation(OSError, ValueError): ...
 class IOBase:
     def __iter__(self) -> Iterator[bytes]: ...
     def __next__(self) -> bytes: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, exc_type: Optional[Type[BaseException]], exc_val: Optional[BaseException], exc_tb: Optional[TracebackType]
     ) -> Optional[bool]: ...
@@ -79,7 +77,7 @@ class FileIO(RawIOBase, BinaryIO):
     def closefd(self) -> bool: ...
     def write(self, __b: ReadableBuffer) -> int: ...
     def read(self, __size: int = ...) -> bytes: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
 
 class BytesIO(BufferedIOBase, BinaryIO):
     def __init__(self, initial_bytes: bytes = ...) -> None: ...
@@ -87,7 +85,7 @@ class BytesIO(BufferedIOBase, BinaryIO):
     # to allow BytesIO sub-classes to add this field, as it is defined
     # as a read-only property on IO[].
     name: Any
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def getvalue(self) -> bytes: ...
     def getbuffer(self) -> memoryview: ...
     if sys.version_info >= (3, 7):
@@ -96,7 +94,7 @@ class BytesIO(BufferedIOBase, BinaryIO):
         def read1(self, __size: Optional[int]) -> bytes: ...  # type: ignore
 
 class BufferedReader(BufferedIOBase, BinaryIO):
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
     def peek(self, __size: int = ...) -> bytes: ...
     if sys.version_info >= (3, 7):
@@ -105,12 +103,12 @@ class BufferedReader(BufferedIOBase, BinaryIO):
         def read1(self, __size: int) -> bytes: ...  # type: ignore
 
 class BufferedWriter(BufferedIOBase, BinaryIO):
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
     def write(self, __buffer: ReadableBuffer) -> int: ...
 
 class BufferedRandom(BufferedReader, BufferedWriter):
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
     def seek(self, __target: int, __whence: int = ...) -> int: ...
     if sys.version_info >= (3, 7):
@@ -165,7 +163,7 @@ class TextIOWrapper(TextIOBase, TextIO):
             write_through: Optional[bool] = ...,
         ) -> None: ...
     # These are inherited from TextIOBase, but must exist in the stub to satisfy mypy.
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __iter__(self) -> Iterator[str]: ...  # type: ignore
     def __next__(self) -> str: ...  # type: ignore
     def writelines(self, __lines: Iterable[str]) -> None: ...  # type: ignore

stdlib/lzma.pyi

@@ -1,6 +1,6 @@
 import io
-from _typeshed import ReadableBuffer, StrOrBytesPath
-from typing import IO, Any, Mapping, Optional, Sequence, TextIO, TypeVar, Union, overload
+from _typeshed import ReadableBuffer, Self, StrOrBytesPath
+from typing import IO, Any, Mapping, Optional, Sequence, TextIO, Union, overload
 from typing_extensions import Literal
 
 _OpenBinaryWritingMode = Literal["w", "wb", "x", "xb", "a", "ab"]
@@ -9,7 +9,6 @@ _OpenTextWritingMode = Literal["wt", "xt", "at"]
 _PathOrFile = Union[StrOrBytesPath, IO[bytes]]
 
 _FilterChain = Sequence[Mapping[str, Any]]
-_T = TypeVar("_T")
 
 FORMAT_AUTO: int
 FORMAT_XZ: int
@@ -76,7 +75,7 @@ class LZMAFile(io.BufferedIOBase, IO[bytes]):
         preset: Optional[int] = ...,
         filters: Optional[_FilterChain] = ...,
     ) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def close(self) -> None: ...
     @property
     def closed(self) -> bool: ...

stdlib/mailbox.pyi

@@ -1,6 +1,6 @@
 import email.message
 import sys
-from _typeshed import StrOrBytesPath
+from _typeshed import Self, StrOrBytesPath
 from types import TracebackType
 from typing import (
     IO,
@@ -189,7 +189,7 @@ class _ProxyFile(Generic[AnyStr]):
     def tell(self) -> int: ...
     def seek(self, offset: int, whence: int = ...) -> None: ...
     def close(self) -> None: ...
-    def __enter__(self) -> _ProxyFile[AnyStr]: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, exc_type: Optional[Type[BaseException]], exc: Optional[BaseException], tb: Optional[TracebackType]
     ) -> None: ...

stdlib/nntplib.pyi

@@ -2,9 +2,9 @@ import datetime
 import socket
 import ssl
 import sys
-from typing import IO, Any, Dict, Iterable, List, NamedTuple, Optional, Tuple, TypeVar, Union
+from _typeshed import Self
+from typing import IO, Any, Dict, Iterable, List, NamedTuple, Optional, Tuple, Union
 
-_SelfT = TypeVar("_SelfT", bound=_NNTPBase)
 _File = Union[IO[bytes], bytes, str, None]
 
 class NNTPError(Exception):
@@ -46,7 +46,7 @@ class _NNTPBase:
     nntp_implementation: str
     nntp_version: int
     def __init__(self, file: IO[bytes], host: str, readermode: Optional[bool] = ..., timeout: float = ...) -> None: ...
-    def __enter__(self: _SelfT) -> _SelfT: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: Any) -> None: ...
     def getwelcome(self) -> str: ...
     def getcapabilities(self) -> Dict[str, List[str]]: ...

stdlib/pathlib.pyi

@@ -1,5 +1,13 @@
 import sys
-from _typeshed import OpenBinaryMode, OpenBinaryModeReading, OpenBinaryModeUpdating, OpenBinaryModeWriting, OpenTextMode, StrPath
+from _typeshed import (
+    OpenBinaryMode,
+    OpenBinaryModeReading,
+    OpenBinaryModeUpdating,
+    OpenBinaryModeWriting,
+    OpenTextMode,
+    Self,
+    StrPath,
+)
 from io import BufferedRandom, BufferedReader, BufferedWriter, FileIO, TextIOWrapper
 from os import PathLike, stat_result
 from types import TracebackType
@@ -54,7 +62,7 @@ class PureWindowsPath(PurePath): ...
 
 class Path(PurePath):
     def __new__(cls: Type[_P], *args: StrPath, **kwargs: Any) -> _P: ...
-    def __enter__(self: _P) -> _P: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, exc_type: Optional[Type[BaseException]], exc_value: Optional[BaseException], traceback: Optional[TracebackType]
     ) -> Optional[bool]: ...

stdlib/runpy.pyi

@@ -1,19 +1,18 @@
+from _typeshed import Self
 from types import ModuleType
-from typing import Any, Dict, Optional, TypeVar
-
-_T = TypeVar("_T")
+from typing import Any, Dict, Optional
 
 class _TempModule:
     mod_name: str = ...
     module: ModuleType = ...
     def __init__(self, mod_name: str) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: Any) -> None: ...
 
 class _ModifiedArgv0:
     value: Any = ...
     def __init__(self, value: Any) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self) -> None: ...
     def __exit__(self, *args: Any) -> None: ...
 
 def run_module(

stdlib/select.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import FileDescriptorLike
+from _typeshed import FileDescriptorLike, Self
 from types import TracebackType
 from typing import Any, Iterable, List, Optional, Tuple, Type
 
@@ -101,7 +101,7 @@ if sys.platform != "linux" and sys.platform != "win32":
 if sys.platform == "linux":
     class epoll(object):
         def __init__(self, sizehint: int = ..., flags: int = ...) -> None: ...
-        def __enter__(self) -> epoll: ...
+        def __enter__(self: Self) -> Self: ...
         def __exit__(
             self,
             exc_type: Optional[Type[BaseException]] = ...,

stdlib/selectors.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import FileDescriptor, FileDescriptorLike
+from _typeshed import FileDescriptor, FileDescriptorLike, Self
 from abc import ABCMeta, abstractmethod
 from typing import Any, List, Mapping, NamedTuple, Optional, Tuple
 
@@ -26,7 +26,7 @@ class BaseSelector(metaclass=ABCMeta):
     def get_key(self, fileobj: FileDescriptorLike) -> SelectorKey: ...
     @abstractmethod
     def get_map(self) -> Mapping[FileDescriptorLike, SelectorKey]: ...
-    def __enter__(self) -> BaseSelector: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: Any) -> None: ...
 
 class SelectSelector(BaseSelector):

stdlib/socket.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import ReadableBuffer, WriteableBuffer
+from _typeshed import ReadableBuffer, Self, WriteableBuffer
 from collections.abc import Iterable
 from enum import IntEnum, IntFlag
 from io import RawIOBase
@@ -545,7 +545,7 @@ class socket(_socket.socket):
         proto: int = ...,
         fileno: Optional[int] = ...,
     ) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: object) -> None: ...
     def dup(self: _T) -> _T: ...  # noqa: F811
     def accept(self) -> tuple[socket, _RetAddress]: ...

stdlib/socketserver.pyi

@@ -1,5 +1,6 @@
 import sys
 import types
+from _typeshed import Self
 from socket import socket as _socket
 from typing import Any, BinaryIO, Callable, ClassVar, Optional, Set, Tuple, Type, TypeVar, Union
 
@@ -30,7 +31,7 @@ class BaseServer:
     def server_activate(self) -> None: ...
     def server_bind(self) -> None: ...
     def verify_request(self, request: _RequestType, client_address: _AddressType) -> bool: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, exc_type: Optional[Type[BaseException]], exc_val: Optional[BaseException], exc_tb: Optional[types.TracebackType]
     ) -> None: ...

stdlib/subprocess.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import StrOrBytesPath
+from _typeshed import Self, StrOrBytesPath
 from types import TracebackType
 from typing import IO, Any, AnyStr, Callable, Generic, Mapping, Optional, Sequence, Tuple, Type, TypeVar, Union, overload
 from typing_extensions import Literal
@@ -34,7 +34,6 @@ if sys.platform == "win32":
 else:
     _ENV = Union[Mapping[bytes, StrOrBytesPath], Mapping[str, StrOrBytesPath]]
 
-_S = TypeVar("_S")
 _T = TypeVar("_T")
 
 class CompletedProcess(Generic[_T]):
@@ -1007,7 +1006,7 @@ class Popen(Generic[AnyStr]):
     def send_signal(self, sig: int) -> None: ...
     def terminate(self) -> None: ...
     def kill(self) -> None: ...
-    def __enter__(self: _S) -> _S: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, type: Optional[Type[BaseException]], value: Optional[BaseException], traceback: Optional[TracebackType]
     ) -> None: ...

stdlib/sunau.pyi

@@ -1,4 +1,5 @@
 import sys
+from _typeshed import Self
 from typing import IO, Any, NamedTuple, NoReturn, Optional, Union
 
 _File = Union[str, IO[bytes]]
@@ -30,7 +31,7 @@ class _sunau_params(NamedTuple):
 
 class Au_read:
     def __init__(self, f: _File) -> None: ...
-    def __enter__(self) -> Au_read: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: Any) -> None: ...
     def getfp(self) -> Optional[IO[bytes]]: ...
     def rewind(self) -> None: ...
@@ -50,7 +51,7 @@ class Au_read:
 
 class Au_write:
     def __init__(self, f: _File) -> None: ...
-    def __enter__(self) -> Au_write: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, *args: Any) -> None: ...
     def setnchannels(self, nchannels: int) -> None: ...
     def getnchannels(self) -> int: ...