Re: Programmatically loading completion for another command?

[Bart Schaefer <schaefer@brasslantern.com>]

On Fri, May 27, 2022 at 12:58 PM Vorpal <zsh@vorpal.se> wrote:
>
> > Bart Schaefer wrote on Fri, 27 May 2022 17:03 +00:00:
> >>
> >>    service=makepkg _sequence $_comps[makepkg]
>
> Thanks a lot! That works mostly as expected. There is one issue in that
> exclusivity in the argument completion of makepkg is ignored.

It looks like _sequence assumes that whatever function it calls will
understand the -F -S and -r options of compadd (and won't fail if
passed them anyway).  Most of the uses of _sequence in the Completion/
tree are "_sequence compadd ..." and several others call functions
that eventually just do "compadd $@ ...".  For a completion function
that uses _arguments to have any hope of working with this, it would
at least have to include something like
  local -a compadd_args=( "$@" )
  ...
  _arguments ... -O compadd_args ...
and even that might not work in many cases, because _arguments doesn't
pass those options to every possible compadd.

A helper function for _sequence could be created to assist with this.

> However it seems to me that a generic helper on the following form would
> a useful addition to the standard zsh distribution in that case:
>
> _complete_for()
> {
>      service=$1 $_comps[$1]
> }

If you have a wrapper, you might as well go all the way:

_complete_for () {
  local service=$1
  shift
  local compadd_args=(${(q)@})
  {
    eval "function compadd { builtin compadd $compadd_args \"\$@\" }"
    $_comps[$service]
  } always {
    unfunction compadd
  }
}

That needs some work to avoid conflicting with other helpers that
redefine compadd, but seems to get the basic job done.