Conflict with venv on Python 3.12

[nfg]

Hello!

We ran into a weird issue at work today when we tried upgrading from Python 3.11 to Python 3.12. When we run virtualenv-tools --update-path, we get an error:

(venv) 😿  cristina ./venv/bin/virtualenv-tools --update-path /newpath/venv venv/
Traceback (most recent call last):
  File "/Users/local_nigel/cristina/./venv/bin/virtualenv-tools", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/Users/local_nigel/cristina/venv/lib/python3.12/site-packages/virtualenv_tools.py", line 351, in main
    venv = _get_original_state(path=args.path)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/local_nigel/cristina/venv/lib/python3.12/site-packages/virtualenv_tools.py", line 317, in _get_original_state
    orig_path=get_orig_path(path),
              ^^^^^^^^^^^^^^^^^^^
  File "/Users/local_nigel/cristina/venv/lib/python3.12/site-packages/virtualenv_tools.py", line 263, in get_orig_path
    raise AssertionError(
AssertionError: Could not find VIRTUAL_ENV= in activation script: venv/bin/activate

I did some investigation. The activate script installed by venv on 3.12 looks like this:

# on Windows, a path can contain colons and backslashes and has to be converted:
if [ "${OSTYPE:-}" = "cygwin" ] || [ "${OSTYPE:-}" = "msys" ] ; then
    # transform D:\path\to\venv to /d/path/to/venv on MSYS
    # and to /cygdrive/d/path/to/venv on Cygwin
    export VIRTUAL_ENV=$(cygpath "/Users/local_nigel/cristina/venv")
else
    # use the path as-is
    export VIRTUAL_ENV="/Users/local_nigel/cristina/venv"
fi

When I set up a virtual environment using virtualenv, it looks like this:

VIRTUAL_ENV='/Users/local_nigel/cristina/venv'
if ([ "$OSTYPE" = "cygwin" ] || [ "$OSTYPE" = "msys" ]) && $(command -v cygpath &> /dev/null) ; then
    VIRTUAL_ENV=$(cygpath -u "$VIRTUAL_ENV")
fi
export VIRTUAL_ENV

We're using venv to generate our virtual environments because it's part of the standard library. I can update our build scripts to use virtualenv, but it'd be really nice if this tool worked with activate as generated by venv. 😁

Cheers!