Unable to access previous or initial state about redux-toolkit HOT 4 CLOSED

Hmm. At the start of the function, the draft object should represent the latest state, so you should be able to just use that as a starting point for any comparisons.

I guess I'm not really seeing what the issue is here. Can you give a specific example, preferably with a CodeSandbox repro, of something you want to do that isn't working correctly?

from redux-toolkit.

Sure,

import { createReducer } from "redux-starter-kit";
export const initialState = {
  result: []
};

const Notifications = createReducer(initialState, {
  TEST(state, action) {
    console.log(state.result);
  }
});

Notifications(undefined, { type: "TEST" });

In the above example I'd expect the log to be [] but it is instead a Proxy object. I'm presuming this is because the draft object is passed as the 'state' and the actual state object is inaccessible. So I can write to the state, but I cannot read from it. Or have I misunderstood?

A use case for this might be wanting to compare a value on the existing state object before deciding what to update on the draft

Link - https://codesandbox.io/s/2v017oozy0 (needs browser console)

It looks like Immer supports passing an object as the third argument to pre-populate the draft. Perhaps that would solve the issue?

from redux-toolkit.

Immer is using a Proxy to wrap the state object, but as far as I know it should still let you access the underlying state as normal if you need to read values.

If I do console.log(state.result.length) in that sandbox, I see it print 3, as expected.

from redux-toolkit.

Ah, okay. I think that even though I'm not seeing [] I can still access things like .map() and .length.

Thanks for your time!

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