Determination of duplicate stylesheets

duplicate-stylesheets.js

/**
 * Поиск дублированных стилей
 *
 * @param {Mixed} collection Коллекция
 */
function duplicates(collection) {
    var maps = [], path = '', key = 0;

    if (!Array.isArray(collection)) {
        collection = [].slice.apply(collection);
    }

    collection.forEach(function(resource) {
        path = resource.href || resource.src;
        if (!path) {
            return;
        }

        if (maps.indexOf(path) !== -1) {
            return console.info(
                '%cDuplicate resource: ' + path,
                'background: yellow; color: #000; font-weight: 700; padding: 1px 4px;'
            );
        }

        maps.push(path);
    });
}