[Feature request] Alias a single flag to a set of multiple flags

[gfscott]

Do you want to request a feature or report a bug?

Feature request!

What is the current behavior?

Currently, it's easy to declare flag aliases on a 1:1 basis:

User input	Alias that runs
command --old-flag	command --new-flag

What is the expected behavior?

What I'd like to be able to do is declare flag aliases on a 1:many basis — create a flag that aliases multiple existing flags, to provide users with shortcuts to a sensible set of options:

User input	Aliased flags that run
order --combo	order --burger --fries --shake=strawberry

Purely spitballing, but here's an idea of how I might reasonably expect to configure this:

export default class Order extends Command {
  static description = 'Place your order';
  static flags = {  
    burger: Flags.string({/***/}),
    fries: Flags.boolean({/***/}),
    shake: Flags.string({/***/}),
    combo: Flags.boolean({
      default: false,
      description: 'The chef’s special :)',
      groupAlias: [
        { flag: 'burger' },     // flag has default value, therefore no option required
        { flag: 'fries' },      // flag is a boolean, no option required
        {
          flag: 'shake',
          option: 'strawberry'  // flag is a string with no default value, so option is required
        }, 
      ]
    }),
  }
}

I think something like this would make it easier to support common use cases and workflows, while preserving composability and granularity for power users. Thanks!

[mdonnalley]

@gfscott This is a neat idea.

We've been considering adding a preparse hook that would allow people to manipulate the raw flags and args before they're parsed. I think such a feature would be able to support your idea. Essentially you would see if --combo is present and then add the other flags to the set of flags that will be parsed.

Implementing that feature is behind a few things other things on our roadmap so I'll keep this feature request open in the meantime