The template() function in lib/web/mage/utils/template.js returns «undefined» values as a string, not as the «undefined» global variable nor «null» literal, which lead to mistakes in the core code's logical expressions

dmitrii_fediuk · February 1, 2016, 8:47pm

magento/magento2/blob/c53d060/lib/web/mage/utils/template.js#L35-L44


/**
 * Evaluates template string using ES6 templates.
 *
 * @param {String} tmpl - Template string.
 * @param {Object} $ - Data object used in a template.
 * @returns {String} Compiled template.
 */
template = function (tmpl, $) {
    return eval('`' + tmpl + '`');
};

An example of mistake: The beforeSave() method in app/code/Magento/Ui/view/base/web/js/form/client.js tries to make AJAX requests for undefined URLs