'use strict'; module.exports = function diffAssoc(values) { let diffValues = values; if (values instanceof this.constructor) { diffValues = values.all(); } const collection = {}; Object.keys(this.items).forEach((key) => { if (diffValues[key] === undefined || diffValues[key] !== this.items[key]) { collection[key] = this.items[key]; } }); return new this.constructor(collection); };