Mocking an ajax request when testing epics
Often in unit tests we are focussing on the logic involved in crafting a network request, & how we respond to the result. The external service is unlikely to be under our control, so we need a way to ‘mock’ the Ajax request in a way that allows us to focus on the logic. In this lesson we’ll see how we can pass in dependencies into epics to make testing things Ajax requests easier.
I think the current methods for testing isn't great.
You need to make significant changes to the epic code - the example given added parameters to the epic but more changes were made to this code before the lesson started when compared to previous lessons - the following function was defined outside of the epic in earlier lessons but in this lesson it is inside the epic. const ajax = term => Observable.ajax.getJSON(search(term))
You need to change code when setting up epic middleware
I don't think the idea of changing code to suit a test is good practice
Hi. I've been following along, and it all seems to be working, accept my test only receives one ACTION rather than two.
{ type: 'SEARCHED_BEERS_LOADING', payload: true }
But I don't get
{ type: RECEIVED_BEERS, payload: beers }
When I should.
Also, .toArray() on the subscribe is not working for me??
Cheers.
What happens at 6:32 in your video shows exactly why isn't a good idea to change your function to fit the test. Basically you are forcing your method to adapt to your tests and by doing so you are generating a false positive as your test pass but still will not work in production because you are sending the wrong object.