So I saved this file as _gocomp in a directory:

#compdef go

local -a options
options=('run:description for run' 'build:description for build')
_describe 'values' options

after $ fpath=($(readlink -f .) $fpath) and autload -U _gocomp, I try to
type go [TAB]. zsh greets me with `go _gocomp`.

What am I doing wrong?