Testing javascript alerts with Jasmine

Question

I'm writing some Jasmine tests for some legacy javascript that produces an alert or a confirm at some points in the code.

At the moment where the alert pops up it pauses execution in the browser requiring me to press ok before going on.

I'm sure I'm missing something but is there a way of faking an alert?

Even better is it possible to find out what the message was for the alert?

Thanks for your help.

Answer 1

spyOn(window, 'alert');
. . . 
expect(window.alert).toHaveBeenCalledWith('a message');

Answer 2

var oldalert = alert;
alert = jasmine.createSpy();
// do something
expect(alert).toHaveBeenCalledWith('message')
alert = oldalert

Answer 3

Another way is to do this in spec helper.

window.alert = function(){return;};

Or if you need the message.

var actualMessage = ''; 
window.alert = function(message){actualMessage = message; return;}