Method parse_ref

crates/cli-flags/src/opt.rs:181–289

(
        &self,
        cmd: &clap::Command,
        arg: Option<&clap::Arg>,
        value: &std::ffi::OsStr,
    )

    type Value = CommaSeparated<T>;

    fn parse_ref(
        &self,
        cmd: &clap::Command,
        arg: Option<&clap::Arg>,
        value: &std::ffi::OsStr,
    ) -> Result<Self::Value, Error> {
        let val = StringValueParser::new().parse_ref(cmd, arg, value)?;

        let options = T::OPTIONS;
        let arg = arg.expect("should always have an argument");
        let arg_long = arg.get_long().expect("should have a long name specified");
        let arg_short = arg.get_short().expect("should have a short name specified");

        // Handle `-O help` which dumps all the `-O` options, their messages,
        // and then exits.
        if val == "help" {
            let mut max = 0;
            for d in options {
                max = max.max(d.name.display_string().len() + d.val_help.len());
            }
            println!("Available {arg_long} options:\n");
            for d in options {
                print!(
                    "  -{arg_short} {:>1$}",
                    d.name.display_string(),
                    max - d.val_help.len()
                );
                print!("{}", d.val_help);
                print!(" --");
                if val == "help" {
                    for line in d.docs.lines().map(|s| s.trim()) {
                        if line.is_empty() {
                            break;
                        }
                        print!(" {line}");
                    }
                    println!();
                } else {
                    println!();
                    for line in d.docs.lines().map(|s| s.trim()) {
                        let line = line.trim();
                        println!("        {line}");
                    }
                }
            }
            println!("\npass `-{arg_short} help-long` to see longer-form explanations");
            std::process::exit(0);
        }
        if val == "help-long" {
            println!("Available {arg_long} options:\n");
            for d in options {
                println!(
                    "  -{arg_short} {}{} --",
                    d.name.display_string(),
                    d.val_help
                );
                println!();
                for line in d.docs.lines().map(|s| s.trim()) {