Confused w Karma: How to test location.pathname?

I'm writing a router and using Karma for TDD. I'm all good with the setup and unit testing with Mocha/Chai/Sinon. My question is, using Karma, how can I test that the browser's location path has changed?

In my router, I'm doing:

window.history.pushState(route.params, route.title, route.path);

And this of course changes the location in the browser when NOT using Karma. In my unit test, I was expecting something like:

it('should map deps and execute on navigation', function() { 
app
  .route('/profile', 'profile')
  .controller('profile', [function() {
    expect(location.pathname).to.equal('/profile');
  }])
  .navigate('/profile');

});

But location.pathname equates to the Karma '/context.html'

How can I assert the location pathname was changed using Karma? Should I mock window?