Bug report

Bug description:

Hi! The following code reliably produces some unicode replacement characters �, on Windows, always in the same location. Works fine on Linux.

This report is a follow-up to this other one: #82052

A fix was already attempted, but as you can see, there are still some cases uncovered.

Example 1

print('é'*20001)

Example 2

This is an attempt at making a shorter example, and a bit of a stretch goal.

python -c "import sys;[sys.stdout.buffer.raw.write(b) for b in [b'\xc3', b'\xa9',b'\xc3\xa9']]"

CPython versions tested on:

3.10, 3.12

Operating systems tested on:

Linux, Windows

Linked PRs

• gh-110913: Fix WindowsConsoleIO chunking of UTF-8 text #111007
• [3.12] gh-110913: Fix WindowsConsoleIO chunking of UTF-8 text (GH-111007) #111108
• [3.11] gh-110913: Fix WindowsConsoleIO chunking of UTF-8 text (GH-111007) #111109