From 5dbdd59c9b8a543427db41114bbde9f9a36363a2 Mon Sep 17 00:00:00 2001
From: Alex Waygood <Alex.Waygood@Gmail.com>
Date: Thu, 26 Oct 2023 18:41:31 +0100
Subject: [PATCH] Add `io.text_encoding` on py310+ (#10929)

See https://discuss.python.org/t/type-checkers-complain-about-io-text-encoding/37187/1 for discussion. The function is documented, even though it's not included in `io.__all__` (which is why stubtest hasn't been complaining about it being missing): https://docs.python.org/3/library/io.html#io.text_encoding
---
 stdlib/io.pyi | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/stdlib/io.pyi b/stdlib/io.pyi
index c114f8395..b54e0a9fd 100644
--- a/stdlib/io.pyi
+++ b/stdlib/io.pyi
@@ -6,7 +6,7 @@ from _typeshed import FileDescriptorOrPath, ReadableBuffer, WriteableBuffer
 from collections.abc import Callable, Iterable, Iterator
 from os import _Opener
 from types import TracebackType
-from typing import IO, Any, BinaryIO, TextIO
+from typing import IO, Any, BinaryIO, TextIO, TypeVar, overload
 from typing_extensions import Literal, Self
 
 __all__ = [
@@ -33,6 +33,8 @@ __all__ = [
 if sys.version_info >= (3, 8):
     __all__ += ["open_code"]
 
+_T = TypeVar("_T")
+
 DEFAULT_BUFFER_SIZE: Literal[8192]
 
 SEEK_SET: Literal[0]
@@ -194,3 +196,9 @@ class IncrementalNewlineDecoder(codecs.IncrementalDecoder):
     @property
     def newlines(self) -> str | tuple[str, ...] | None: ...
     def setstate(self, __state: tuple[bytes, int]) -> None: ...
+
+if sys.version_info >= (3, 10):
+    @overload
+    def text_encoding(__encoding: None, __stacklevel: int = 2) -> Literal["locale", "utf-8"]: ...
+    @overload
+    def text_encoding(__encoding: _T, __stacklevel: int = 2) -> _T: ...