Unit Test on $state in function - angularjs

Question

I have a function that triggers to change page. How can I unit test this? I'm always getting a failed result saying:
Expected ' ' to be 'add'
So the current state name is still the home page
Function
$scope.goToAddVote = function(){
$state.go('add');
}
Unit Testing
it('should redirect index.html to add.html after click on button', inject(function($state) {
scope.goToAddVote();
$state.go('add');
expect($state.current.name).toBe('add');
}));
EDIT: Using Nilo's answer
var mockStateService = {
go: jasmine.createSpy('add')
};
it('should redirect index.html to add.html after click on button', inject(function($state) {
scope.goToAddVote();
$state.go('add');
expect(mockStateService.go).toHaveBeenCalledWith('add');
}));

Answer 1

Your unit test is failing because the state you are trying to recieve is never registered in the first place. Thats why the go function will have no effect which ends in your current state-name being ''
What you should do ist inject a mock of the $state service with a jasmine-spy as a replacement for the go-function. In your assertion you then expect this function to have been called.
This is way cleaner in terms of unit-testing, because you do not also test the capabilities of $state.
The mocked service would look something along the lines of this:
var mockStateService = {
go: jasmine.createSpy()
}
The assertion then should look like this:
expect(mockStateService.go).toHaveBeenCalledWith('add');
EDIT: Your result could also be caused by the fact mentioned by Pankaj Parkar. So you can also try that, but either why you should mock the service so you really only test the code you have written yourself.
EDIT2: You are not injecting the mocked service, but still using the original $state
var mockStateService,
myScope,
ctrl;
beforeEach(inject(function($controller, $rootScope) {
mockStateService = {
go: jasmine.createSpy()
}
myScope = $rootScope.$new();
ctrl = $controller('myController', {
$scope: myScope,
$state: mockStateService
});
}));
// tip: write better descriptions, what you are writing is not what's really happening
it('should redirect index.html to add.html after click on button', function() {
myScope.goToAddVote();
expect(mockStateService.go).toHaveBeenCalledWith('add');
});