Testing a debounced function in AngularJS with Jasmine never calls the function

Question

I have a method in a service that uses underscore's debounce.

Inside that method is a call to a method on a different service. I'm trying to test that the different service is called.

In my attempts to test the debounced method, the different services' method is never called, and jasmine fails with:

"Expected spy aMethod to have been called."

I know for a fact that it IS called (it logs to console in chrome), it's just called AFTER the expectation already failed.

So... (preferably) without adding Sinon or another dependency and with
bonus points* given to a solution doesn't have to turn the _.debounce into a $timeout...

How do?

angular.module('derp', [])
.service('herp', function(){ 
   return {
     aMethod: function(){ 
       console.log('called!'); 
       return 'blown'; 
     }
   }; 
 })
 .service('Whoa', ['herp', function(herp){
   function Whoa(){
     var that = this;
     this.mindStatus = 'meh';
     this.getMind = _.debounce(function(){
       that.mindStatus = herp.aMethod();
     }, 300);
   }
   return Whoa;
 }]);

tests:

describe('Whoa', function(){
  var $injector, whoa, herp;

  beforeEach(function(){
    module('derp');
    inject(function(_$injector_){
      var Whoa;
      $injector = _$injector_;
      Whoa = $injector.get('Whoa');
      herp = $injector.get('herp');
      whoa = new Whoa();
    });
  });

  beforeEach(function(){
    spyOn(herp, 'aMethod').andCallThrough();
  });

  it('has a method getMind, that calls herp.aMethod', function(){
    whoa.getMind();
    expect(herp.aMethod).toHaveBeenCalled();
  });
});

Why have the AngularJS Testing gods forsaken me?

* I do not know how to give actual bonus points on stackoverflow, but if it is possible, i will.

Answer 1

You just need to mock lodash debounce method:

describe('Whoa', function(){
  var $injector, whoa, herp;

  beforeEach(function(){
    module('derp');
    spyOn(_, 'debounce').and.callFake(function(cb) { return function() { cb(); } });
    inject(function(_$injector_){
      var Whoa;
      $injector = _$injector_;
      Whoa = $injector.get('Whoa');
      herp = $injector.get('herp');
      whoa = new Whoa();
    });
  });

  beforeEach(function(){
    spyOn(herp, 'aMethod').andCallThrough();
  });

  it('has a method getMind, that calls herp.aMethod', function(){
    whoa.getMind();
    expect(herp.aMethod).toHaveBeenCalled();
  });
});