Jest Redux Persist: TypeError: Cannot read property 'catch' of undefined at writeStagedState

Question

I'm trying to test my LoginScreen with Jest and Typescript. I use redux and redux-persist for storage and have set the storage up to use AsyncStorage as part of the config. I suspect that redux-persist is attempting to rehydrate after the built-in time-out function it uses runs out and tries to set storage to default storage? I'm getting the following error:

console.error
redux-persist: rehydrate for "root" called after timeout. undefined
undefined
at _rehydrate (node_modules/redux-persist/lib/persistReducer.js:70:71)
at node_modules/redux-persist/lib/persistReducer.js:102:11
at tryCallOne (node_modules/promise/setimmediate/core.js:37:12)
at Immediate._onImmediate (node_modules/promise/setimmediate/core.js:123:15)

Currently my test looks like this:

describe('Testing LoginScreen', () => {
  it('should render correctly', async () => {
    const { toJSON } = render(<MockedNavigator component={LoginScreen} />);
    await act(async () => await flushMicrotasksQueue());
    expect(toJSON()).toMatchSnapshot();
  });
});

and my MockNavigator looks like this:

type MockedNavigatorProps = {
  component: React.ComponentType<any>;
  params?: {};
};

const Stack = createStackNavigator();
const MockedNavigator = (props: MockedNavigatorProps) => {
  return (
    <MockedStorage>
      <NavigationContainer>
        <Stack.Navigator>
          <Stack.Screen
            name='MockedScreen'
            component={props.component}
            initialParams={props.params}
          />
        </Stack.Navigator>
      </NavigationContainer>
    </MockedStorage>
  );
};

export default MockedNavigator;

Here is the way I'm creating my storage:

import 'react-native-gesture-handler';
import * as React from 'react';
import { Provider } from 'react-redux';
import { PersistGate } from 'redux-persist/integration/react';
import { store, persistor } from '../src/AppState/store';

type MockedStorageProps = {
  children: any;
};

const MockedStorage = (props: MockedStorageProps) => {
  return (
    <Provider store={store}>
      <PersistGate loading={null} persistor={persistor}>
        {props.children}
      </PersistGate>
    </Provider>
  );
};

export default MockedStorage;

Answer 1

I resolved this same error using this advice from an issue on the redux-persist repo: https://github.com/rt2zz/redux-persist/issues/1243#issuecomment-692609748.

(It also had the side-effect of avoiding logging errors in test from redux-logger.)

jest.mock('redux-persist', () => {
  const real = jest.requireActual('redux-persist');
  return {
    ...real,
    persistReducer: jest
      .fn()
      .mockImplementation((config, reducers) => reducers),
  };
});

@alexbrazier:

It basically just bypasses redux-persist by returning the reducers directly without wrapping them in redux-persist.