Handling State with useReducer and useContext in a Complex Nested Component Structure
I'm writing unit tests and I'm learning this framework and I'm maintaining legacy code that I'm currently building a complex form with multiple nested components in React 18, and I'm using `useReducer` along with `useContext` to manage the global state of the form values. However, I'm running into issues where changes made in deeply nested components do not properly trigger re-renders in parent components. I have a context provider set up like this: ```javascript const FormContext = React.createContext(); const formReducer = (state, action) => { switch (action.type) { case 'UPDATE_FIELD': return { ...state, [action.field]: action.value }; default: return state; } }; export const FormProvider = ({ children }) => { const [state, dispatch] = useReducer(formReducer, {}); return ( <FormContext.Provider value={{ state, dispatch }}> {children} </FormContext.Provider> ); }; ``` In my nested component, I'm trying to dispatch an action like this: ```javascript const NestedInput = () => { const { state, dispatch } = useContext(FormContext); const handleChange = (e) => { dispatch({ type: 'UPDATE_FIELD', field: 'nestedField', value: e.target.value }); }; return <input value={state.nestedField || ''} onChange={handleChange} />; }; ``` I assumed that each time I update the state in the nested component, it would re-render the parent component, but it seems like the parent does not update unless its own state changes. I also receive a warning: `want to read properties of undefined (reading 'nestedField')` when the component first mounts, which I suspect is because the initial state is `{}` and there's no `nestedField` yet. I've tried initializing the state with an object that includes `nestedField`, but it seems like the scenario continues. Is there a best practice for handling state in such nested components to ensure that the re-renders happen as expected? Any insights or solutions would be appreciated. I'm working with Javascript in a Docker container on Ubuntu 20.04. Any pointers in the right direction? This issue appeared after updating to Javascript 3.9. Any help would be greatly appreciated! For context: I'm using Javascript on Ubuntu 20.04. Has anyone else encountered this? Is there a simpler solution I'm overlooking?