Usage string broken for ArgGroup of option and argument

[joshtriplett]

Consider the following subcommand definition:

    SubCommand::with_name("set-base")
        .about("Set the base commit for the patch series")
        .arg(Arg::with_name("base").help("Base commit").required(false))
        .arg_from_usage("-d, --delete 'Remove the base commit information'")
        .group(ArgGroup::with_name("base_or_delete")
            .args(&["base", "delete"])
            .required(true)),

(The same issue applies if I use arg_from_usage for base.)

The usage string looks like this:

    set-base [FLAGS] [[base]|--delete] [ARGS]
...
    [base]    Base commit

Note the extra square brackets around base; that part should look like base|--delete.

Also, the alternative between base and --delete should probably have something other than square brackets around it, since one of those two is required.

[joshtriplett]

An interesting further complication: if I add a .conflicts_with("delete") to base, and pass both, I get the following error:

error: The argument '--delete' cannot be used with '[base]'

USAGE:
    git series set-base [base] --delete [[base]|--delete] [[base]|--delete]

That seems like two too many of each argument.

[joshtriplett]

Using .required_unless("delete") instead of .conflicts_with("delete") produces slightly better results, but still a bit wrong:

USAGE:
    set-base [FLAGS] <base> [<base>|--delete]

<base> shouldn't appear twice.

[kbknapp]

Thanks for taking the time to file these! I agree with all of the above, so it's actually like 3 bugs in 1, or a formating one for the first comment which is an easy fix that I agree with too.

I'll post back here as they're completed then put out 2.4.1.

[kbknapp]

Tracking for issues:

• Duplicated args in usage string
• formatting for required arg groups
• formatting for positional arguments

[kbknapp]

@joshtriplett All tasks done, this should be merged with #499 at which point I'll put out v2.4.1

[kbknapp]

due to some crazy test issues and refactoring woes, the next version is actually v2.4.3 and is out on crates.io. This is the version that has the changes from this issue 😉 Sorry for the confusion!