Re: [RFC PATCH 1/3] python: add mkvenv.py

[Paolo Bonzini]

On 3/28/23 23:11, John Snow wrote:
> +        # venv class is cute and toggles this off before post_setup,
> +        # but we need it to decide if we want to generate shims or not.

Ha, yeah that's a bug in the venv package.  post_setup() can already run 
with system_site_packages reverted to True.

> +            for entry_point in entry_points:
> +                # Python 3.8 doesn't have 'module' or 'attr' attributes
> +                if not (hasattr(entry_point, 'module') and
> +                        hasattr(entry_point, 'attr')):
> +                    match = pattern.match(entry_point.value)
> +                    assert match is not None
> +                    module = match.group('module')
> +                    attr = match.group('attr')
> +                else:
> +                    module = entry_point.module
> +                    attr = entry_point.attr
> +                yield {
> +                    'name': entry_point.name,
> +                    'module': module,
> +                    'import_name': attr,
> +                    'func': attr,

What about using a dataclass or namedtuple instead of a dictionary?

> +
> +    try:
> +        entry_points = _get_entry_points()
> +    except ImportError as exc:
> +        logger.debug("%s", str(exc))
> +        raise Ouch(
> +            "Neither importlib.metadata nor pkg_resources found, "
> +            "can't generate console script shims.\n"
> +            "Use Python 3.8+, or install importlib-metadata, or setuptools."
> +        ) from exc

Why not put this extra try/except inside _get_entry_points()?

> +
> +    # Test for ensurepip:
> +    try:
> +        import ensurepip

Use find_spec()?

BTW, another way to repair Debian 10's pip is to create a symbolic link 
to sys.base_prefix + '/share/python-wheels' in sys.prefix + 
'/share/python-wheels'.  Since this is much faster, perhaps it can be 
done unconditionally and checkpip mode can go away together with 
self._context?

Paolo