Redux Toolkit - action from one slice to be caught in another slice - redux-toolkit

Question

There's an action (addOrder) in an orderSlice
orderSlice.js
import { createSlice } from '#reduxjs/toolkit';
const initialState = {
orders: []
};
const ordersSlice = createSlice({
name: 'orders',
initialState,
reducers: {
addOrder: {
reducer: (state, action) => {
state.orders.push(action.payload)
},
prepare: (orderItems, orderTotal) => {
const orderDate = new Date().toDateString();
return { payload: { orderDate, orderItems: orderItems, orderTotal: orderTotal }}
}
}
}
})
export const { addOrder } = ordersSlice.actions;
export default ordersSlice.reducer;
I'd like it to also affect the state in another slice (cartSlice). Once the 'addOrder' is fired, it should also bring the cartReducer to its initial state. Some googling suggested that I should use extrareducers for that but I'm really not getting its syntax. See below (not valid code in extrareducers)
cartSlice
import { createSlice } from '#reduxjs/toolkit';
import { addOrder } from './ordersSlice';
const initialState = {
items: {},
totalAmount: 0
};
const cartSlice = createSlice({
name: 'cart',
initialState: initialState,
reducers: {
addToCart: (state, action) => {
// p = product to be added or amended
const p = action.payload;
if (state.items[p.id]) {
// already exists
state.items[p.id].quantity += 1;
state.items[p.id].sum += p.price;
state.totalAmount += p.price;
} else {
state.items[p.id] = { price: p.price, quantity: 1, title: p.title, sum: p.price};
state.totalAmount += p.price;
}
},
removeFromCart: (state, action) => {
console.log('remove from cart');
console.log(action.payload);
const currentQuantity = state.items[action.payload].quantity;
console.log(currentQuantity);
if (currentQuantity > 1) {
state.items[action.payload].quantity -= 1;
state.items[action.payload].sum -= state.items[action.payload].price;
state.totalAmount -= state.items[action.payload].price;
} else {
state.totalAmount -= state.items[action.payload].price;
delete state.items[action.payload];
}
}
},
extraReducers: (builder) => {
builder
.addCase(addOrder(state) => {
return initialState;
})
}
});
export const { addToCart, removeFromCart } = cartSlice.actions;
export default cartSlice.reducer;

Answer 1

You're almost there! The builder.addCase function takes two arguments. The first is the action creator and the second is the case reducer. So you need a comma after addOrder.
extraReducers: (builder) => {
builder.addCase(addOrder, (state) => {
return initialState;
});
}