Replacing state with a different slice does not work

[chris-dem]

I am using a reducer path test. Depeding on the url path, I want to inject a different state. Issue is that, after my first slice is injected, I am not seeing any updates to my state, even after enabling the overrideExisting flag. Am I missing something?

[markerikson]

I have no idea what you're trying to do here. There's no code, and I don't know what you mean by "replace state" vs "inject a different state".

[chris-dem]

That still doesn't work, tried toggling an action but the state stayed the same.

[EskiMojo14]

any chance you could put together a minimal reproduction of this?

[chris-dem]

Can you try with this sandbox? https://codesandbox.io/p/sandbox/redux-toolkit-playground-forked-r58wj5

[EskiMojo14]

it's called initialState for a reason - it's only used when the reducer is called with undefined. In this case, we already have state for this reducer, so it's using that state instead and returning it.

let reducer1 = (state = { id: 1 }, action) => state;

let reducer2 = (state = { id: 2 }, action) => state;

let state = reducer1(undefined, { type: "INIT" });

state = reducer2(state, { type: "REPLACE" });

// state is still { id: 1 }

[chris-dem]

So what would you recommend to do if I want to replace the state using the original state. And also what is the point of the overrideExisting?

[EskiMojo14]

overrideExisting allows replacing the reducer, which is entirely different from replacing the state.

At a guess, I suspect you would need to wrap your slice reducer in a function that detects if the state is from the other reducer and replaces it before the slice reducer handles it.

Overall this isn't something we'd consider a common use case - we'd expect a given reducer in a given location to always handle the same data.

[chris-dem]

I see thank you