Magento2: How can I override core js module price-box.js

Question

I need to extend Magento_Catalog/js/price-box.js. I have used the 'mixins' feature, but it's not working for price-box.js.

requirejs-config.js:

var config = {
    config: {
        mixins: {
            'Magento_Catalog/js/price-box': {
                'My_Module/js/price-box/pluggin': true
            }
        }
    }
};

My_Module/view/frontend/web/js/price-box/pluggin.js

define(function () {
    'use strict';

    return function (target) { 
        // modify target
        var reloadPrice = target.reloadPrice;
        target.reloadPrice = function() {
           cosole.log("hello");
        };
        return target;
    };
});

Answer 1

1. Specify PriceBox js file in your custom module's requirejs-config.js with the same name by which its already declared in core modules. in our case it is priceBox like below. Your modules requirejs-config.js would be something like

   var config = {
       map: {
            '*': {
                   priceBox:'namespace_modulename/js/custompricebox',
            }
       }
   };
   

2. Now, create the file custompricebox.js to the path specified above. i am assuming you want to extend reloadPrice method in price-box. so your custompricebox.js would be like below.

   define(
       [
           'jquery',
           'Magento_Catalog/js/price-utils',
           'underscore',
           'mage/template',
           'mage/priceBox',
           'jquery/ui'
       ],
       function ($, utils, _, mageTemplate) {
   
           'use strict';
   
           $.widget('yournamespace.custompriceBox', $.mage.priceBox, {
               /**
                * Render price unit block.
                */
               reloadPrice: function reDrawPrices() {
   
                   var priceFormat = (this.options.priceConfig && this.options.priceConfig.priceFormat) || {},
                       priceTemplate = mageTemplate(this.options.priceTemplate);
   
                   _.each(this.cache.displayPrices, function (price, priceCode) {
                       price.final = _.reduce(price.adjustments, function(memo, amount) {
                           return memo + amount;
                       }, price.amount);
   
                       // you can put your custom code here. 
   
                       price.formatted = utils.formatPrice(price.final, priceFormat);
   
                       $('[data-price-type="' + priceCode + '"]', this.element).html(priceTemplate({data: price}));
                   }, this);
               },
   
   
           });
   
           return $.yournamespace.custompriceBox;
       }
   );
   

3. Please note this code is not tested. there might be some syntex errors. let me know if you need more help on this.