yarn-completion: "counter" and "cmd" must be set by the caller and be the appropriate type

Currently any tab completion after yarn ends with this message and exit. Seems to me that a declare cmd does not make it in the check before the exit.

joma@edison:~$ homestead ssh
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Last login: Tue Apr  3 23:03:34 2018 from 10.0.2.2
vagrant@homestead:~$ bash --version
GNU bash, version 4.3.48(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
vagrant@homestead:~$ set -v
vagrant@homestead:~$ . ~/.yarn-completion
vagrant@homestead:~$ yarn __yarn_get_package_fields scripts
pwd
cword=1
words[0]=${!ref}${COMP_WORDS[i]}
words[1]=${!ref}${COMP_WORDS[i]}
cword=1
words=("${@:3:2}")
cword="$3"
cur="$3"
cur="$3"
cword="$3"
prev="$3"
words=("${@:3:2}")
declare -p counter cmd 2>/dev/null | awk '{ printf "%s", $2 }'
"counter" and "cmd" must be set by the caller and be the appropriate type
logout
# ~/.bash_logout: executed by bash(1) when login shell exits.

# when leaving the console clear the screen to increase privacy

if [ "$SHLVL" = 1 ]; then
    [ -x /usr/bin/clear_console ] && /usr/bin/clear_console -q
fi
Connection to 127.0.0.1 closed.