How do you spy on AngularJS's $timeout with Jasmine? - unit-testing

Question

I am trying to spy on $timeout so that I can verify that it has not been called. Specifically, my production code (see below) calls $timeout as a function, not an object:
$timeout(function() { ... })
and not
$timeout.cancel() // for instance
Jasmine, however, requires an object to be spied upon, like this:
spyOn(someObject, '$timeout')
I don't know what 'someObject' would be though.
I am using Angular mocks, if that makes any difference.
Edit: The relevant production code I'm trying to test looks like this:
EventHandler.prototype._updateDurationInOneSecondOn = function (call) {
var _this = this;
var _updateDurationPromise = this._$timeout(function () {
call.duration = new Date().getTime() - call.startTime;
_this._updateDurationInOneSecondOn(call);
}, 1000);
// ... more irrelevant code
}
In the specific test scenario I am trying to assert that $timeout was never called.
Edit 2: Specified clearly that I am using $timeout as a function, not an object.

Answer 1

Ran into the same problem and ended up decorating the $timeout service with a spy.
beforeEach(module(function($provide) {
$provide.decorator('$timeout', function($delegate) {
return sinon.spy($delegate);
});
}));
Wrote more about why this works here.

Answer 2

In angular $timeout is a service that executes/calls a function. The request to "spy" $timeout is a bit odd being the case that what it is doing is executing X function in Y given time. What I would do to spy this services is to "mock" the timeout function and inject it in your controller something like:
it('shouldvalidate time',inject(function($window, $timeout){
function timeout(fn, delay, invokeApply) {
console.log('spy timeout invocation here');
$window.setTimeout(fn,delay);
}
//instead of injecting $timeout in the controller you can inject the mock version timeout
createController(timeout);
// inside your controller|service|directive everything stays the same
/* $timeout(function(){
console.log('hello world');
x = true;
},100); */
var x = false; //some variable or action to wait for
waitsFor(function(){
return x;
},"timeout",200);
...

Answer 3

This code works for me
var element, scope, rootScope, mock = {
timeout : function(callback, lapse){
setTimeout(callback, lapse);
}
};
beforeEach(module(function($provide) {
$provide.decorator('$timeout', function($delegate) {
return function(callback, lapse){
mock.timeout(callback, lapse);
return $delegate.apply(this, arguments);
};
});
}));
describe("when showing alert message", function(){
it("should be able to show message", function(){
rootScope.modalHtml = undefined;
spyOn(mock, 'timeout').and.callFake(function(callback){
callback();
});
rootScope.showMessage('SAMPLE');
expect(rootScope.modalHtml).toBe('SAMPLE');
});
});