01-test.t

use Test;
use Test::Output;
use File::Directory::Tree;

use CLI;

# you can comment one of the subtests block and it will still print the text.

subtest 'no arguments provided' => {
    output-like {CLI::MAIN()}, /Execute/, "show help message";
}

subtest 'version command' => {
    output-like {CLI::MAIN(:version)}, /Documentable\sversion/, "long version";
}

done-testing;

CLI.pm6

package CLI {

    sub RUN-MAIN(|c) is export {
        my %*SUB-MAIN-OPTS = :named-anywhere;
        CORE::<&RUN-MAIN>(|c)
    }

    our proto MAIN(|) is export { * }

    multi MAIN (
        "setup",
        Bool :y(:$yes) = False
    ) {
        say "setup";
    }

    multi MAIN (
        "start"                           ,
        Str  :$topdir              = "doc",                   
        Str  :$conf                = "config.json", 
        Bool :v(:verbose($v))      = False,                   
        Bool :p(:primary($p))      = False,                   
        Bool :s(:secondary($s))    = False,                   
        Bool :$search-index        = False,                   
        Bool :i(:indexes($i))      = False,                   
        Bool :t(:typegraph($t))    = False,                   
        Bool :f(:force($f))        = False,                   
        Bool :$highlight           = False,                   
        Str  :$typegraph-file      = "type-graph.txt",        
        Str  :$highlight-path      = "./highlights",          
        Str  :$dirs?,                                         
        Bool :a(:$all)             = False                    
    ) {
        say "start";
    }

    multi MAIN (
        "update",
        Str  :$topdir          = "doc",
        Str  :$conf            = "config.json", 
        Bool :v(:$verbose)     = True ,                   
        Bool :$highlight       = False,
        Str  :$highlight-path  = "./highlights"
    ) {}

    multi MAIN (
        "clean"
    ) {
        say "clean";
    }

    multi MAIN (
        Bool :V(:$version)!
    ) {
        say "version";
    }

    multi MAIN() {
        note 'Execute "documentable --help" for more information.';
    }

}