change United States to USA in Gravity Forms addresses, with support for Gravity Forms Address Enhanced

gf-country-usa.php

<?php
/*
Plugin Name: GF Country USA
Plugin URI: https://gist.github.com/webaware/edba921af11f06bdfd5147bab806f591
Description: change United States to USA in Gravity Forms addresses
Version: 2
Author: WebAware
Author URI: https://shop.webaware.com.au/
*/

/*
copyright (c) 2020-2022 WebAware Pty Ltd (email : support@webaware.com.au)

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

if (!defined('ABSPATH')) {
    exit;
}

/**
 * change United States to show as USA
 * @param array $countries
 * @return array
 */
add_filter('gform_countries', function($countries) {
    $key = array_search('United States', $countries);
    $countries[$key] = 'USA';
    sort($countries);

    return $countries;
});

/**
 * change GF Address Enhanced's map of country names to country codes
 * @param array $countries
 * @return array
 */
add_filter('gf_address_enhanced_countries', function($countries) {
    unset($countries[translate('United States', 'gravityforms')]);
    $countries['USA'] = 'US';

    return $countries;
});