AngularJS - How to test if a function is called from within another function?

Question

I'm trying to get started with karma-jasmine and I'm wondering why this test fails:

it("should call fakeFunction", function() {
    spyOn(controller, 'addNew');
    spyOn(controller, 'fakeFunction');
    controller.addNew();
    expect(controller.fakeFunction).toHaveBeenCalled();
});

In my controller that I've previously set up for this test I have the following:

function addNew() {
    fakeFunction(3);
}

function fakeFunction(number) {
    return number;
}

both addNew and fakeFunction are exposed using:

vm.addNew = addNew;
vm.fakeFunction = fakeFunction;

The test, however, fails with the following:

Expected spy fakeFunction to have been called.

I can make the test pass if I call the function from within my test. I was hoping, however, I could test if fakeFunction was called by another function. What is the proper way to achieve this?

Update:

//test.js

beforeEach(function() {

    module("app");

    inject(function(_$rootScope_, $controller) {

        $scope = _$rootScope_.$new();
        controller = $controller("CreateInvoiceController", {$scope: $scope});

    });

});

If I test something like:

it('should say hello', function() {
    expect(controller.message).toBe('Hello');
});

The test passes if I put the following in my controller:

var vm = this;
vm.message = 'Hello';

I just want to know how I can test if a public function was called from another function.

Answer 1

I just came across this problem myself. The previous answer by @Vadim has the right principles but I don't think everything was very clear. In my case, I am trying to call a public function on a service from within another function. Here are the relevant snippets:

Service:

angular.module('myApp').factory('myService', function() {

    function doSomething() {
      service.publicMethod();
    }

    function publicMethod(){
      // Do stuff
    }

    var service = {
      publicMethod: publicMethod
    };

    return service;
});

Test:

it('calls the public method when doing something', function(){
  spyOn(service, 'publicMethod');

  // Run stuff to trigger doSomething()

  expect(service.publicMethod).toHaveBeenCalled();
});

The key here is that the function being tested needs to be calling the same reference as the public function that is being spy'd on.