title: How to mock Google Analytics function call ga()
body: <p>I have a service <em>MyService</em> with a function using the <code>ga()</code> event tracking call which I want to test: </p>
  
  <pre><code>angular.module('myModule').factory('MyService', [function() {
  
      var myFunc = function() {
          ga('send', 'event', 'bla');
          // do some stuff
      }
  
      return {
          myFunc: myFunc
      }
  ]);
  </code></pre>
  
  <p>My spec file looks like this:</p>
  
  <pre><code>describe('The MyService', function () {
  
      var MyService,
          ga;
  
      beforeEach(function () {
          module('myModule');
          ga = function() {};
      });
  
      beforeEach(inject(function (_MyService_) {
          MyService = _MyService_;
      }));
  
      it('should do some stuff', function () {
          MyService.myFunc();
          // testing function
      });
  });
  </code></pre>
  
  <p>Running my tests always gives me:</p>
  
  <blockquote>
    <p>ReferenceError: Can't find variable: ga</p>
  </blockquote>