How do I spy on an Angular promise chain using Jasmine - angularjs

Question

Using AngularJS, CoffeeScript and Jasmine (edited in WebStorm), I would like to unit test a chain of promises.
Lets say I have the following example service:
Angular Service
class ExampleService
stepData: []
constructor: (#$http) ->
attachScopeMethod: (#scope) ->
#scope.callSteps = => #step1().then -> #step2()
step1: ->
#$http.get('app/step/1').then (results) =>
#stepData[0] = results.data
results
step2: ->
#$http.get('app/step/2').then (results) =>
#stepData[2] = results.data
results
This service allows me to attach a the method callSteps() to the scope. This method, when called, executes a series of asynch $http calls to a 3rd party API.
To test that each step is at least called, I have written the following Jasmine spec.
Jasmine Spec
ddescribe 'ExampleService', ->
beforeEach ->
module 'myApp'
beforeEach inject ($rootScope, $injector) ->
#scope = $rootScope.$new()
#exampleService = $injector.get 'exampleService'
#q = $injector.get '$q'
describe 'process example steps', ->
beforeEach ->
#exampleService.attachScopeMethod(#scope)
it "should attach the scope method", ->
expect(#scope.callSteps).toBeDefined()
describe 'when called should invoke the promise chain', ->
it "should call step1 and step2", ->
defer = #q.defer()
#exampleService.step1 = jasmine.createSpy('step1').andReturn(defer.promise)
#exampleService.step2 = jasmine.createSpy('step2')
#scope.callSteps()
defer.resolve()
expect(#exampleService.step1).toHaveBeenCalled()
expect(#exampleService.step2).toHaveBeenCalled()
The results of this test is as follows:
expect(#exampleService.step1).toHaveBeenCalled() - PASS
expect(#exampleService.step2).toHaveBeenCalled() - FAIL
Can you tell me how I can get step2() to succesfully run under test?
Thank you
EDIT
#Dashu below kindly supplied the answer to the problem. The trick is to simply call scope.$apply or scope.$digest to trigger the promise chain resolution.
So here is the working test fragment.
describe 'when called should invoke the promise chain', ->
it "should call step1 and step2", ->
defer = #q.defer()
defer.resolve()
#exampleService.step1 = jasmine.createSpy('step1').andReturn(defer.promise)
#exampleService.step2 = jasmine.createSpy('step2')
#scope.callSteps()
#scope.$apply()
expect(#exampleService.step1).toHaveBeenCalled()
expect(#exampleService.step2).toHaveBeenCalled()

Answer 1

try a $rootScope.$apply() before the second expect
also about defer.resolve(). i don't know if this actually resolves the promise, i think it just setups the value to return when it resolves.
so i would move that up to just underneath the $q.defer() call, before passing the promise to the andReturn()
you could do defer.resolve(true), defer.reject(false), so if you're promise will get rejected insinde callsteps, true or false will be returned