Use _typeshed.Self with __enter__ (#5712)

stdlib/@python2/_io.pyi

@@ -1,3 +1,4 @@
+from _typeshed import Self
 from mmap import mmap
 from typing import IO, Any, BinaryIO, Iterable, List, Optional, Text, TextIO, Tuple, Type, TypeVar, Union
 
@@ -30,7 +31,7 @@ class _IOBase(BinaryIO):
     def tell(self) -> int: ...
     def truncate(self, size: Optional[int] = ...) -> int: ...
     def writable(self) -> bool: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, t: Optional[Type[BaseException]], value: Optional[BaseException], traceback: Optional[Any]
     ) -> Optional[bool]: ...
@@ -56,7 +57,7 @@ class _BufferedIOBase(_IOBase):
 class BufferedRWPair(_BufferedIOBase):
     def __init__(self, reader: _RawIOBase, writer: _RawIOBase, buffer_size: int = ..., max_buffer_size: int = ...) -> None: ...
     def peek(self, n: int = ...) -> bytes: ...
-    def __enter__(self) -> BufferedRWPair: ...
+    def __enter__(self: Self) -> Self: ...
 
 class BufferedRandom(_BufferedIOBase):
     mode: str
@@ -140,7 +141,7 @@ class _TextIOBase(TextIO):
     def writable(self) -> bool: ...
     def write(self, pbuf: unicode) -> int: ...
     def writelines(self, lines: Iterable[unicode]) -> None: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, t: Optional[Type[BaseException]], value: Optional[BaseException], traceback: Optional[Any]
     ) -> Optional[bool]: ...

stdlib/builtins.pyi

@@ -7,6 +7,7 @@ from _typeshed import (
     OpenBinaryModeWriting,
     OpenTextMode,
     ReadableBuffer,
+    Self,
     StrOrBytesPath,
     SupportsDivMod,
     SupportsKeysAndGetItem,
@@ -648,7 +649,7 @@ class memoryview(Sized, Sequence[int]):
     contiguous: bool
     nbytes: int
     def __init__(self, obj: ReadableBuffer) -> None: ...
-    def __enter__(self) -> memoryview: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, exc_type: Optional[Type[BaseException]], exc_val: Optional[BaseException], exc_tb: Optional[TracebackType]
     ) -> None: ...

stdlib/bz2.pyi

@@ -1,7 +1,7 @@
 import _compression
 import sys
 from _compression import BaseStream
-from _typeshed import ReadableBuffer, StrOrBytesPath, WriteableBuffer
+from _typeshed import ReadableBuffer, Self, StrOrBytesPath, WriteableBuffer
 from typing import IO, Any, Iterable, List, Optional, Protocol, TextIO, TypeVar, Union, overload
 from typing_extensions import Literal, SupportsIndex
 
@@ -82,7 +82,7 @@ def open(
 ) -> TextIO: ...
 
 class BZ2File(BaseStream, IO[bytes]):
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     if sys.version_info >= (3, 9):
         @overload
         def __init__(self, filename: _WritableFileobj, mode: _WriteBinaryMode, *, compresslevel: int = ...) -> None: ...

stdlib/cProfile.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import StrOrBytesPath
+from _typeshed import Self, StrOrBytesPath
 from types import CodeType
 from typing import Any, Callable, Dict, Optional, Tuple, TypeVar, Union
 
@@ -8,7 +8,6 @@ def runctx(
     statement: str, globals: Dict[str, Any], locals: Dict[str, Any], filename: Optional[str] = ..., sort: Union[str, int] = ...
 ) -> None: ...
 
-_SelfT = TypeVar("_SelfT", bound=Profile)
 _T = TypeVar("_T")
 _Label = Tuple[str, int, str]
 
@@ -23,11 +22,11 @@ class Profile:
     def dump_stats(self, file: StrOrBytesPath) -> None: ...
     def create_stats(self) -> None: ...
     def snapshot_stats(self) -> None: ...
-    def run(self: _SelfT, cmd: str) -> _SelfT: ...
-    def runctx(self: _SelfT, cmd: str, globals: Dict[str, Any], locals: Dict[str, Any]) -> _SelfT: ...
+    def run(self: Self, cmd: str) -> Self: ...
+    def runctx(self: Self, cmd: str, globals: Dict[str, Any], locals: Dict[str, Any]) -> Self: ...
     def runcall(self, __func: Callable[..., _T], *args: Any, **kw: Any) -> _T: ...
     if sys.version_info >= (3, 8):
-        def __enter__(self: _SelfT) -> _SelfT: ...
+        def __enter__(self: Self) -> Self: ...
         def __exit__(self, *exc_info: Any) -> None: ...
 
 def label(code: Union[str, CodeType]) -> _Label: ...  # undocumented

stdlib/codecs.pyi

@@ -1,5 +1,6 @@
 import sys
 import types
+from _typeshed import Self
 from abc import abstractmethod
 from typing import (
     IO,
@@ -188,8 +189,6 @@ class BufferedIncrementalDecoder(IncrementalDecoder):
     def _buffer_decode(self, input: bytes, errors: str, final: bool) -> Tuple[str, int]: ...
     def decode(self, input: bytes, final: bool = ...) -> str: ...
 
-_SW = TypeVar("_SW", bound=StreamWriter)
-
 # TODO: it is not possible to specify the requirement that all other
 # attributes and methods are passed-through from the stream.
 class StreamWriter(Codec):
@@ -198,14 +197,12 @@ class StreamWriter(Codec):
     def write(self, object: str) -> None: ...
     def writelines(self, list: Iterable[str]) -> None: ...
     def reset(self) -> None: ...
-    def __enter__(self: _SW) -> _SW: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, typ: Optional[Type[BaseException]], exc: Optional[BaseException], tb: Optional[types.TracebackType]
     ) -> None: ...
     def __getattr__(self, name: str, getattr: Callable[[str], Any] = ...) -> Any: ...
 
-_SR = TypeVar("_SR", bound=StreamReader)
-
 class StreamReader(Codec):
     errors: str
     def __init__(self, stream: IO[bytes], errors: str = ...) -> None: ...
@@ -213,7 +210,7 @@ class StreamReader(Codec):
     def readline(self, size: Optional[int] = ..., keepends: bool = ...) -> str: ...
     def readlines(self, sizehint: Optional[int] = ..., keepends: bool = ...) -> List[str]: ...
     def reset(self) -> None: ...
-    def __enter__(self: _SR) -> _SR: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, typ: Optional[Type[BaseException]], exc: Optional[BaseException], tb: Optional[types.TracebackType]
     ) -> None: ...
@@ -237,7 +234,7 @@ class StreamReaderWriter(TextIO):
     def reset(self) -> None: ...
     # Same as write()
     def seek(self, offset: int, whence: int = ...) -> int: ...
-    def __enter__(self: _T) -> _T: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, typ: Optional[Type[BaseException]], exc: Optional[BaseException], tb: Optional[types.TracebackType]
     ) -> None: ...
@@ -275,7 +272,7 @@ class StreamRecoder(BinaryIO):
     def writelines(self, list: Iterable[bytes]) -> int: ...  # type: ignore  # it's supposed to return None
     def reset(self) -> None: ...
     def __getattr__(self, name: str) -> Any: ...
-    def __enter__(self: _SRT) -> _SRT: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self, type: Optional[Type[BaseException]], value: Optional[BaseException], tb: Optional[types.TracebackType]
     ) -> None: ...

stdlib/contextlib.pyi

@@ -1,4 +1,5 @@
 import sys
+from _typeshed import Self
 from types import TracebackType
 from typing import (
     IO,
@@ -80,7 +81,7 @@ class ExitStack(ContextManager[ExitStack]):
     def callback(self, callback: Callable[..., Any], *args: Any, **kwds: Any) -> Callable[..., Any]: ...
     def pop_all(self: _U) -> _U: ...
     def close(self) -> None: ...
-    def __enter__(self: _U) -> _U: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(
         self,
         __exc_type: Optional[Type[BaseException]],

stdlib/fileinput.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import StrOrBytesPath
+from _typeshed import Self, StrOrBytesPath
 from typing import IO, Any, AnyStr, Callable, Generic, Iterable, Iterator, Union
 
 if sys.version_info >= (3, 10):
@@ -78,7 +78,7 @@ class FileInput(Iterable[AnyStr], Generic[AnyStr]):
         ) -> None: ...
     def __del__(self) -> None: ...
     def close(self) -> None: ...
-    def __enter__(self) -> FileInput[AnyStr]: ...
+    def __enter__(self: Self) -> Self: ...
     def __exit__(self, type: Any, value: Any, traceback: Any) -> None: ...
     def __iter__(self) -> Iterator[AnyStr]: ...
     def __next__(self) -> AnyStr: ...

stdlib/ftplib.pyi

@@ -1,12 +1,10 @@
-from _typeshed import SupportsRead, SupportsReadline
+from _typeshed import Self, SupportsRead, SupportsReadline
 from socket import socket
 from ssl import SSLContext
 from types import TracebackType
-from typing import Any, Callable, Dict, Iterable, Iterator, List, Optional, TextIO, Tuple, Type, TypeVar, Union
+from typing import Any, Callable, Dict, Iterable, Iterator, List, Optional, TextIO, Tuple, Type, Union
 from typing_extensions import Literal
 
-_T = TypeVar("_T")
-
 MSG_OOB: int
 FTP_PORT: int
 MAXLINE: int
@@ -34,7 +32,7 @@ class FTP:
     lastresp: str
     file: Optional[TextIO]
     encoding: str
-    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]
     ) -> None: ...