* Use UTF-8 for Python code-execution subprocess I/O
Studio's code-execution tool already tells the child to emit UTF-8
(PYTHONIOENCODING=utf-8 in _build_safe_env), but _python_exec writes the
temp script and decodes the subprocess pipe with the OS default codec.
On Windows (cp1252), non-ASCII in model-written code or its output --
arrows, CJK, emoji -- raises UnicodeEncodeError / UnicodeDecodeError and
breaks execution.
Complete the UTF-8 wiring in core/inference/tools.py:
- write the temp script with encoding="utf-8"
- decode _python_exec stdout as utf-8, errors="replace"
- set PYTHONIOENCODING=utf-8 in _build_bypass_env too (matches
_build_safe_env, so the bypass path's child also emits utf-8)
The child is python with PYTHONIOENCODING=utf-8, so it emits UTF-8
regardless of the console code page and the decode is always correct.
Shell execution via cmd.exe has a separate console-code-page story and
is left to a follow-up.
Refs unslothai/unsloth#6489
* Scope Python exec UTF-8 env to Python tool
* Make bash bypass test robust to a host-set PYTHONIOENCODING for PR #6548
Bypass mode preserves benign host env vars, so a host-set PYTHONIOENCODING was
inherited into the bash bypass env and tripped the new assertion even though
_bash_exec never adds it. Clear it in the test so the assertion checks _bash_exec,
not the runner environment.
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Co-authored-by: Lee Jackson <130007945+Imagineer99@users.noreply.github.com>
Co-authored-by: Daniel Han <danielhanchen@gmail.com>
