Tox: unclear argument description

[jugmac00]

This parser argument ...

https://github.com/tox-dev/tox/blob/3edd7dc4e902cc99e921cb60193226e5ead52079/src/tox/session/state.py#L109-L119

gets rendered as ...

What does "default execute" mean?

Maybe change the help text to "specify runner"?

[jugmac00]

The interesting part: Why is default empty, and not virtualenv like on my cli?

I guess this relates to REGISTER.default_run_env only gets set during runtime of tox and not right from the beginning.

I think there is not much we can do? cc @gaborbernat

[gaborbernat]

The parser is setup for the doc generation here https://github.com/tox-dev/tox/blob/rewrite/docs/cli_interface.rst, so we could inject here https://github.com/tox-dev/tox/blob/rewrite/src/tox/config/cli/parse.py#L62 customization to set any values we might want.

[jugmac00]

Ok, so I had a deep dive into argparse...

Looks like the optional arguments are stored in parser._optionals._actions.

As _actions is a list, I cannot access the runner argument directly, but I would need to iterate over the list like...

for action in tox_parser._optionals._actions:
    if action.dest == "default_runner":
        action.default="virtualenv"
        break

And then create a function like parser_for_doc_generation? Which I would reference from cli_interface.rst?

So it would look like:

.. sphinx_argparse_cli::
  :module: tox.config.cli.parse
  :func: parser_for_doc_generation

and

def parser_for_doc_generation() -> ToxParser:
    parser = _get_parser()
    for action in parser._optionals._actions:
        if action.dest == "default_runner":
            action.default="virtualenv"
            break
    return parser

But possibly there is a better way... @gaborbernat

[gaborbernat]

Rather than patch post creation can't we just make sure it loads the right value during creation?

[jugmac00]

Rather than patch post creation can't we just make sure it loads the right value during creation?

I do use argparse occasionally, but I am not familiar at a deeper level.

When I look at ToxParsers init, it either gets all commands or none (add_cmd).
https://github.com/tox-dev/tox/blob/3addb35bfd56ad077aaf6526d9d479940be4a31c/src/tox/config/cli/parser.py#L122-L136

When we do not use add_subparsers, we would need to add all commands manually? I think that is not what we want.

I also saw a fix_default(s) method - I am not sure whether that would be better, and that's patching, too. So... :shrug: :-)
https://github.com/tox-dev/tox/blob/3addb35bfd56ad077aaf6526d9d479940be4a31c/src/tox/config/cli/parser.py#L41-L55

[gaborbernat]

I'll take a look at why this is not set 👍🏻 and get back to you at a later point in the week.