flux store - unit tests

Question

I'm writing unit tests for several Flux stores and encountered a small annoyance.

My stores are generally built like this:

storeObj = {
...
}

_secretsetterfunction = function (){}

module.exports storeObj

As you can see, since the setter function is outside of the store object - it's not directly accessible.

This presents a problem as the only way to test / manipulate the store data would be to go through the Action -> Dispatcher -> event listener (the Action can technically be cut out) which isn't something I would like to go through when unit testing a store.

The alternative is to actually put the setter methods on the store object - but this isn't something I'd really wish to do.

Any thoughts?

score 4 · Answer 1 · answered Mar 01 '15 at 00:29

4

I had this problem too, using Jasmine.

I wrote a blog post & example repo about how to get a reference to those private inner functions when you're not using Jest: http://bensmithett.com/testing-flux-stores-without-jest/

TL;DR - use rewire

answered Mar 01 '15 at 00:29

Ben

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score 2 · Answer 2 · answered Sep 20 '14 at 21:25

2

Actions are effectively the public api of a store. You only need to verify the effects of actions to fully test your stores.

answered Sep 20 '14 at 21:25

Brigand

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I get that, and it does obviously work. But it can quickly become rather complicated, especially with the waitFor() command. – Guy Nesher Sep 21 '14 at 07:53
Not really, it's actually very simple. You set all of your tests to have a timeout, invoke an action, and you just wait for a change event on the store and validate the payload. There's no simpler way to do it. I do recommend mocha over jasmine... it has better support for this kind of thing afaik. – Brigand Sep 21 '14 at 08:05
I don't think dependencies between React stores are such a good idea. Using principles of CQRS/EventSourcing could help testability and scale better on large teams. See also http://stackoverflow.com/a/25806145/82609 – Sebastien Lorber Sep 22 '14 at 12:52
@SebastienLorber That's quite interesting, but probably going to far for our needs at the moment. – Guy Nesher Sep 25 '14 at 17:51
@FakeRainBrigand agree and that's what we are doing at the moment, still it feels like I'm doing more than a bit of extra work to test these - but I guess this is the best solution atm – Guy Nesher Sep 25 '14 at 17:52

score 0 · Accepted Answer · answered Sep 26 '14 at 16:32

0

So The flux team just addressed this in a blog post, though they are using their own variant called Jest. Still worth a read:

http://facebook.github.io/react/blog/2014/09/24/testing-flux-applications.html?utm_source=javascriptweekly&utm_medium=email

answered Sep 26 '14 at 16:32

Guy Nesher

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flux store - unit tests

3 Answers3