Add more required fields

gistfile1.php

<?php


function my_child_theme_validate_fields( $required_fields ) {
	
	$new_required_fields = array(
		'billing_country' => array(
			'error_id' => 'invalid_billing_country',
			'error_message' => __( 'Please enter your Billing Country', 'edd' )
		)
	);

	$required_fields = array_merge( $new_required_fields, $required_fields );

	return $required_fields;
}
add_filter( 'edd_purchase_form_required_fields', 'my_child_theme_validate_fields' );