How do I register a Thor::Group as a subcommand with arguments

Question

This question started out here. But changed significantly as I learned more about Thor.

I'm trying to make a Thor::Group subcommand that takes an argument. Oddly, it works if there are no arguments.

Can I use a Thor::Group as a sub-command?

This works when I type: foo counter

foo/bin/foo

module Foo
  class CLI < Thor
    register(Counter, 'counter', 'counter', 'Count up from the 1.')
  end

  class Counter < Thor::Group
    desc "Prints 1 2"

    def one
      puts 1
    end

    def two
      puts 2
    end

  end

end

Foo::CLI.start

But this doesn't work when I type: foo counter 5

module Foo
  class CLI < Thor
    register(Counter, 'counter', 'counter <number>', 'Count up from the input.')
  end

  class Counter < Thor::Group
    argument :number, :type => :numeric, :desc => "The number to start counting"
    desc "Prints 2 numbers based on input"

    def one
      puts number + 0
    end

    def two
      puts number + 1
    end

  end


end

Foo::CLI.start

It replies: counter was called incorrectly. Call as foo counter number

Answer 1

I have a solution. Instead of using Thor::Group I'm using Invocations

bin/foo looks like this:

#!/usr/bin/env ruby

require 'foo'

Foo::CLI.start

lib/cli.rb - registers 'generate' as a subtask of of the base command, foo:

module Foo
  class CLI < Thor
    register(Generate, 'generate', 'generate [something]', 'Type foo generate for more help.')
  end
end

lib/generate.rb looks like this:

module Foo

  class Generate < Thor

    desc "project [name]", "Prints the project making step"
    def project(name)
      puts "making first project file #{name}"
      invoke :config
      invoke :project_sub
    end

    desc "config [name]", "Prints the config making step"
    def config(name)
      puts "making first config file #{name}"
      invoke :project_sub
    end

    desc "project_sub [name]", "Prints the project_sub making step"
    def project_sub(name)
      puts "making subsystem file #{name}"
    end

    def self.banner(task, namespace = false, subcommand = true)
       task.formatted_usage(self, true, subcommand).split(':').join(' ')
    end

  end

end

Now I can type: foo generate project fred

and it will output:

> making first project file fred
> making first config file fred
> making subsystem file fred

Notice the banner override. It means that typing: foo generate project with invalid or missing args will give the correct help message:

"project" was called incorrectly. Call as "foo generate project [name]".

as opposed to

"project" was called incorrectly. Call as "foo project [name]".