Subcommand aliases not included in completion scripts

[martinvonz]

Please complete the following tasks

• I have searched the discussions
• I have searched the open and rejected issues

Rust Version

1.63.0

Clap Version

3.2.22

Minimal reproducible code

use std::io::{stdout, Write};
use clap;
use clap::CommandFactory;

#[derive(clap::Parser, Clone, Debug)]
enum App {
    #[clap(alias = "bar")]
    Foo(FooArgs),
}

#[derive(clap::Args, Clone, Debug)]
struct FooArgs {
    my_flag: bool,
}

fn main() {
    let mut app = App::command().disable_help_flag(true).disable_help_subcommand(true);
    let mut buf = vec![];
    clap_complete::generate(clap_complete::Shell::Bash, &mut app, "test", &mut buf);
    stdout().write_all(&mut buf).unwrap();
}

Steps to reproduce the bug with the above code

Run the program to print out a completion script for Bash

Actual Behaviour

Sourcing the completion script and then running test <TAB> will not suggest bar and test bar <TAB> will not suggest --my-flag.

Expected Behaviour

test bar <TAB> should suggest --my-flag. I'm not sure if I think test <TAB> should suggest both foo and bar; perhaps the current behavior of not suggesting aliases is best?

The same bug exists in the Fish completion script. I haven't tried others (or checked the code).

I actually noticed the bug because my tool has jj log command and a jj operation/op log command, and I ran jj op log <TAB>, which suggested arguments that are for jj log. That's because the op (an alias for operation) is ignored and completion is run for jj log instead.

Additional Context

No response

Debug Output

No response

[epage]

alias is hidden in --help and you need visible_alias to show up in --help.

We've had some back and forth on whether things that are hidden from help should show up in completions

• Don't generate completions for args with AppSettings::Hidden #2541
• Support excluding a subcommand from shell completion #1335

When we resolve #3166, my thought is to handle this according to #3951

[martinvonz]

alias is hidden in --help and you need visible_alias to show up in --help.

That makes sense, but it doesn't seem to affect the completion script.

Are you open to a PR to add visible aliases to the completion scripts if I can figure out how?

[epage]

Yes

Supports visible aliases:

• zsh: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/zsh.rs#L170

Doesn't

• bash: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/bash.rs#L104
• elvish: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/elvish.rs#L122
• fish: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/fish.rs#L135
• powershell: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/powershell.rs#L151

[martinvonz]

I've noticed a few other bugs while working on this. Do you prefer that I file separate bugs for those? Looking at past release notes, it doesn't look like you require a bug for each fix, but I don't mind creating them if you prefer.

[epage]

Separate issues are good in case

• There is discussion around the requirements (I prefer PRs to be focused on the implementation)
• In case not all of them get resolved together

I would at least ask for separate commits for each one. If a change is likely to have more discussion, having that in a separate PR helps.

[T0mstone]

Supports visible aliases:

• zsh: https://github.com/clap-rs/clap/blob/master/clap_complete/src/shells/zsh.rs#L170

Although the zsh completion supports listing the aliases for test <TAB>, there is currently still the bug with test bar <TAB> not suggesting --my-flag (or anything else, for that matter).