The collectTypes() method from the Magento_BraintreeTwo's validator.js can be simplified from 8 lines to 1

dmitrii_fediuk · February 27, 2016, 4:32pm

magento/magento2/blob/cf7df72/app/code/Magento/BraintreeTwo/view/base/web/js/validator.js#L60-L77


/**
 * Filter list of available card types
 * @param {Object} availableTypes
 * @param {Object} countrySpecificCardTypes
 * @returns {Object}
 */
collectTypes: function (availableTypes, countrySpecificCardTypes) {
    var key,
        filteredTypes = [];


    for (key in availableTypes) {
        if (_.indexOf(countrySpecificCardTypes, availableTypes[key]) !== -1) {
            filteredTypes.push(availableTypes[key]);
        }
    }


    return filteredTypes;
},

The method produces array intersection by keys, the same as array_intersect_key PHP function.
It can be simplified to the single line:

return _.pick(availableTypes, _.intersection(_.keys(availableTypes), _.keys(countrySpecificCardTypes)));

dmitrii_fediuk · February 27, 2016, 4:37pm