TrailingVarArg with hyphens

[marcbowes]

#278 shows how to use TrailingVarArg and a multiple arg to capture extra args. This works great, but I can't seem to get it working with args that start with hyphens:

[dependencies]
clap = "2.2.4"

extern crate clap;

#[cfg(test)]
mod tests {
    use clap::*;

    #[test]
    fn test_vararg_1() {
        let m = App::new("myprog")
            .setting(AppSettings::TrailingVarArg)
            .subcommand(SubCommand::with_name("sub")
                .setting(AppSettings::TrailingVarArg)
                .arg(Arg::from_usage("<cmd>... 'commands to run'")))
            .get_matches_from(vec!["myprog", "sub", "arg1", "-r", "val1"]);

        let trail: Vec<&str> =
            m.subcommand_matches("sub").unwrap().values_of("cmd").unwrap().collect();
        assert_eq!(trail, ["arg1", "-r", "val1"]);
    }

    #[test]
    fn test_vararg_2() {
        let m = App::new("myprog")
            .setting(AppSettings::TrailingVarArg)
            .subcommand(SubCommand::with_name("sub")
                .setting(AppSettings::TrailingVarArg)
                .arg(Arg::from_usage("<cmd>... 'commands to run'")))
            .get_matches_from(vec!["myprog", "sub", "--arg1", "-r", "val1"]);
       // ^ ERROR due to --arg1
        let trail: Vec<&str> =
            m.subcommand_matches("sub").unwrap().values_of("cmd").unwrap().collect();
        assert_eq!(trail, ["--arg1", "-r", "val1"]);
    }
}

cargo test -- test_vararg_1
     Running target/debug/vararg-e311bd86d802e1d9

running 1 test
test tests::test_vararg_1 ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured

cargo test -- test_vararg_2 
     Running target/debug/vararg-e311bd86d802e1d9

running 1 test
error: Found argument '--arg1' which wasn't expected, or isn't valid in this context

USAGE:
    myprog sub <cmd>...

For more information try --help

[clux]

TrailingVarArg must be set inside the subcommand, or you have to make TrailingVarArg a global setting.

[marcbowes]

Sorry, I messed up the description. Updated.

[kbknapp]

This appears to be a bug, thanks for filing! Like @clux said, the setting should be on the subcommand it affects. You can also use global_setting to set it on the parent command and propagate it down through all the child subcommands. Just an option 😉

I'm looking into this bug now as to why it only works when the first argument doesn't start with a hyphen. I'll post back here with what I find.

[kbknapp]

#560 fixes this.

Also, part of the problem is you need to add AppSettings::AllowLeadingHyphen, because it's also possible to use proper long options and flags with commands that accept TrailingVarArgs, so this distinguishes them.

This should be a passing test once the PR merges:

#[test]
    fn test_vararg_2() {
        let m = App::new("myprog")
            .subcommand(SubCommand::with_name("sub")
                .setting(AppSettings::TrailingVarArg)
                .setting(AppSettings::AllowLeadingHyphen)   // <-- Only change
                .arg(Arg::from_usage("<cmd>... 'commands to run'")))
            .get_matches_from(vec!["myprog", "sub", "--arg1", "-r", "val1"]);
        let trail: Vec<&str> =
            m.subcommand_matches("sub").unwrap().values_of("cmd").unwrap().collect();
        assert_eq!(trail, ["--arg1", "-r", "val1"]);
    }

[marcbowes]

That was fast! Thanks!

Looking forward to the completion work you've done in #560.