Magento 2 How to extend rules.js to add custom validation rules?
you have to set rules.js
inside your theme.
First create folder inside your theme Magento_Ui if its already exist then skip it.
keep file into below location from core module.
app/code/Package/themename/Magento_Ui/web/js/lib/validation/rules.js
Remove var folder. Remove pub/static folder contents and run deploy command,
php bin/magento setup:static-content:deploy
This is the best way to add a new rule without override the file rules.js and use on LayoutProcessor.php or jsLayout.
define( [ 'jquery', 'Magento_Ui/js/lib/validation/validator' ],function ($,validator) { "use strict"; return validator.addRule('validade-name-of-validation', function (value) { return /* your function */ }, $.mage.__('Your error message.') ); });
Enjoy!