Batch activators unexpectedly turn echo off for subsequent commands

[pawelszramowski]

Bug report

Consider the following batch script:

python -m venv venv
CALL venv\Scripts\activate.bat
REM spam
CALL deactivate.bat
REM eggs

The expected output is:

W:\>python -m venv venv

W:\>CALL venv\Scripts\activate.bat

(venv) W:\>REM spam

(venv) W:\>CALL deactivate.bat

W:\>REM eggs

The actual output is:

W:\>python -m venv venv

W:\>CALL venv\Scripts\activate.bat

This is caused by @echo off at the beginning of both scripts that need to be undone after calling them:

python -m venv venv
CALL venv\Scripts\activate.bat
@ECHO ON
REM spam
CALL deactivate.bat
@ECHO ON
REM eggs

Your environment

• CPython versions tested on: Python 3.10.2 (tags/v3.10.2:a58ebcc, Jan 17 2022, 14:12:15) [MSC v.1929 64 bit (AMD64)]

Linked PRs

• gh-96894: Do not turn echo off for subsequent commands in batch activators #96895

[eryksun]

If echo off isn't used, then individual statements have to be prefixed with @ to prevent echoing them. I just implemented this for the new versions of "activate.bat" and "deactivate.bat" that were proposed in issue #88706. Note that ending with echo on would be just as bad, since the caller may have it off. I haven't seen a way to detect the current echo state that doesn't involve ugly hacks such as writing to a temporary file.