tests(Mixed args): Add failing test for mixed argument types

[wezm]

Not sure if I'm missing anything but this code was extracted from my project because the arguments are not being parsed as expected.

It is expected that the added test will pass by assigning the value
config.toml to the config argument and 1 to the feed argument
but it currently fails with the error:

error: The following required arguments were not supplied:
  '<config>'

USAGE:
  mixed_positional_and_options <config> --feed <feed>...

For more information try --help

[Vinatorul]

Thanks for finding and taking the time to do this!
Have you tried to change index for positional from 1 to 2?

[wezm]

Changing to index(2) gives error:

'mixed_positional_and_options' panicked at 'Found positional argument "config" who's index is 2 but there are only 1 positional arguments defined’

[Vinatorul]

Maybe clap decided that config.toml belongs to feed, let's wait for @kbknapp answer.

[kbknapp]

The issue is because --feed is set to multiple(true); so clap doesn't know when --feed stops and config starts. The index only applies to positional arguments, not arguments as a whole because calling the above mixed_positional_and_options config.toml --feed feed works.

The fix is one of three options

• give --feed a bound of values (i.e. one at a time, but still multiple overall by adding number_of_values(1) to --feed this will allow -f feed1 -f feed2 -f feed3)
• use the Unix -- to denote only positional values follow (i.e. $ mixed_positional_and_options --feed feed -- config.toml)
• Re-order the arguments at runtime (as described above), so that config comes before the multiple --feed

[wezm]

Thanks for the info. number_of_values(1) is the behaviour I was after. I will go with that.

[kbknapp]

Glad we could help 😄