Code-Snippets-Functions/Execute a function on a child site/WooCommerce/change-coupon-code-error-message.txt

function filter_woocommerce_coupon_error( $err, $err_code, $coupon ) {
    // Compare
    if ( intval( $err_code ) === WC_COUPON::E_WC_COUPON_INVALID_FILTERED ) {
        // Message
        $err = sprintf( __( 'Sorry, coupon code "%s" is not valid.', 'woocommerce' ), $coupon->get_code() );
    } else {
        $err = 'DEBUG INFORMATION, error code number = ' . intval( $err_code );
    }
    
    return $err;
}
add_filter( 'woocommerce_coupon_error', 'filter_woocommerce_coupon_error', 10, 3 );