d after the fact, and we don&#39;t want that kind of stuff getting in the way of contributing.</p>
<h2 id="why-do-tests-mock-the-browser-apis?"><a href="#why-do-tests-mock-the-browser-apis?">Why do tests mock the browser APIs?</a></h2>
<p>Most notoriously, because it&#39;s impossible to test the router and some side effects properly otherwise. Also, mocks allow the tests to run under Node.js without requiring heavy dependencies like PhantomJS/ChromeDriver/JSDOM.</p>
<p>Another important reason is that it al