/usr/bin/ng script never executes 'else' condition

[tuan]

The ng program that wraps ng-latin seems to require quotes around $NG in the 'if' clause as shown below. Otherwise, if ng-latin or the other ng-* are not installed, the 'exec $NG "$@"' will always execute rather than notifying the user that the none of the ng-* are installed.

if [ -n "$NG" ]; then
  exec $NG "$@"
else
  echo "Neither ng-latin, ng-cjk, nor ng-cjk-canna found."
  echo "Please install what you prefer."
fi

This was found on
Description: Ubuntu 20.04.1 LTS
Release: 20.04

The actual script is /usr/bin/ng and doesn't seem to belong to a package.
Steps:
  uninstall ng-latin, ng-cjk, and ng-cjk-canna
  execute: /usr/bin/ng
Expected:
  message: Neither ng-latin, ng-cjk, nor ng-cjk-canna found.
             Please install what you prefer.
Actual: no output as a result of executing "exec" with no arguments