ES6 analytics.js mock.

analytics.js

(global => {
  'use strict'
  
  // if analytics is already defined, we probably don't need this.
  if (global.analytics) { return }

  class Analytics {
    /**
     * Creates a new instance of the analytics service.
     */
    constructor () {}

    /**
     * Iterates over available trackers on the page and translates the tracking event for each one.
     */
    track (event_name, properties) {
      if (global._gaq) {
        let args = Object.keys(properties).map(key => `${ key }=${ properties[key] }`)
        global._gaq.push(['_trackEvent', event_name, ...args])
      }
      
      if (global.ga) {
        // handle new GA logic...
      }
    }
  }

  global.analytics = new Analytics()
})(window)