jQuery Validate: input just required if another input is filled

Question

I am using jQuery Validate plugin to validate a \"configuration page\". I have a lot of inputs (like Name, Phone, Email...) and for last, \"change password\" section.

I

Answer 1

Try

var $cp = $('#current_password'),
    $np = $('#new_password'),
    $cnp = $('#confirm_new_password');

then

{
    rules: {
        current_password: {
            required: function () {
                return $np.val().length > 0 || $cnp.val().length > 0
            }
        },
        new_password: {
            required: function () {
                return $cp.val().length > 0 || $cnp.val().length > 0
            }
        },
        confirm_new_password: {
            required: function () {
                return $cp.val().length > 0 || $np.val().length > 0
            }
        }
    },
}

Demo: Fiddle