Testing Redux Combined Gearboxes

Question

Let's say I have several gear functions and I combine them into one gear using combineReducers(...) , is there any way to check which gears actually contain a combined gear?

For example, if I have this:

 import { combineReducers } from 'redux' const reducer1 = (state, action) => {...} ... (more reducers, etc) const rootReducer = combineReducers({ reducer1, reducer2, reducer3 }) export default rootReducer 

Can I write a test with Mocha and Expect.js that will let me check if rootReducer reducer2 ? Is it possible?

The way I am currently configured for my project is that each reducer is in a separate file and then imported into a file where the combineReducers(...) function is used to combine them. I am testing all individual gearboxes to verify that they are doing what they should, but I also thought it would be nice to check the combined gearbox to make sure that it contains all the other gearboxes that it should (in case I forget add one example).

thanks

Answer 1

You are testing the wrong thing IMO. You must believe that the combineReducers() function does what it should (it should be tested in Redux distribution tests). But you can create a method that will return an object with reducers to combine as the combineReducers() parameter. This method can and should be tested.