argh==0.31.0 breaks (my) argh.dispatch_command call

[thorwhalen]

Sorry not to give further details but I had the choice between sending a quick issue or not mentioning it at all.

My script, that uses argh, stopped working when I updated to argh==0.31.0 from argh==0.26.2.

The error

    argh.dispatch_command(populate_pkg_dir)
  File "~/.pyenv/versions/p10/lib/python3.10/site-packages/argh/dispatching.py", line 470, in dispatch_command
    set_default_command(parser, function, name_mapping_policy=name_mapping_policy)
  File "~/.pyenv/versions/p10/lib/python3.10/site-packages/argh/assembling.py", line 420, in set_default_command
    inferred_args: List[ParserAddArgumentSpec] = list(
  File "~/.pyenv/versions/p10/lib/python3.10/site-packages/argh/assembling.py", line 183, in infer_argspecs_from_function
    TypingHintArgSpecGuesser.typing_hint_to_arg_spec_params(
  File "~/.pyenv/versions/p10/lib/python3.10/site-packages/argh/assembling.py", line 778, in typing_hint_to_arg_spec_params
    item_type = cls._extract_item_type_from_list_type(first_subtype)
  File "~.pyenv/versions/p10/lib/python3.10/site-packages/argh/assembling.py", line 799, in _extract_item_type_from_list_type
    if args[0] in cls.BASIC_TYPES:
IndexError: tuple index out of range

My guess is that the len(args) == 0 case is not handled properly?

Without looking further, I'd suggest:

 if args and (args[0] in cls.BASIC_TYPES):

instead?

If I have time, I'll look at it further this week and send a PR.

[thorwhalen]

Wrong argh repository.
Copied to the correct one: neithere/argh#216