The "Maximum update depth exceeded" error

[Jonathan_Bean]

The “Maximum update depth exceeded” error is caused by an unstable useEffect hook in src/app/game/play/page.tsx that creates an infinite loop by re-triggering itself. The definitive fix is to remove this hook.

I have attempted to build 3 full apps using the prototyping tool. I have noticed that in Firebase Studio with Next.js projects - Gemini (in the prototype tool) has a really hard time with Maximum depth errors.

Is this likely to be addressed soon?

Is their a way to tell or ask the gemini prototype tool to avoid or watch out for The “Maximum update depth exceeded” error?

Kind regards

Jono

[jamesor]

Thank you @Jonathan_Bean for bringing this to our attention. We are always actively improving code generation.

In the meantime, experiment with setting up an .idx/airules.md file with a few preferences for how AI should make React architectural decisions. This could help avoid errors like the one you mention. It’s also a great way to give Gemini your decision-making preferences.

Note: You MUST restart your workspace for Gemini to read this file and accept new instructions.(CTRL+SHIFT+P > “Firebase Studio: Rebuild Environment” from code mode)

Here is an example I threw together using Gemini that might help with your “maximum depth” issue. Take it with a grain of salt as I didn’t actually test it. However, this could at least serve as a decent starting point for you. If you do have success with this please share back your experience and any improvements you make to it.

Create or append to your .idx/airules.mdfile:

# React

## General rules for component rendering and state updates

1. Avoid direct state modifications in the component's body: Never generate `setState` calls directly within the main function body of a functional component or the `render` method of a class component.  
2. Use event handlers or effects for state updates: Generate `setState` calls only within event handlers (e.g., `onClick`, `onChange`) or within React Hooks like `useEffect`.  
3. Wrap event handler arguments in arrow functions: When passing arguments to a function called by an event handler, ensure the function call is wrapped in an arrow function (e.g., `onClick={() => handleEvent(item)}`). 

## Rules for using the `useEffect` Hook

1. Always include a dependency array: For every `useEffect` Hook, always generate a dependency array as the second argument.  
   1. Empty dependency array (`[]`): Use for effects that should run only once after the initial render and unmount (e.g., fetching data on component mount).  
   2. Dependency array with values (`[value1, value2]`): Include all variables, props, or state that the effect depends on. The effect will re-run only when a value in the dependency array changes.  
   3. Setter functions from `useState`: Exclude these from the dependency array as they are guaranteed to be stable.  
   4. Functions defined inside the component: Include these in the dependency array unless they are memoized with `useCallback` or are setter functions.  
2. Avoid circular state dependencies: When state updates are triggered within a `useEffect`, ensure that the updated state variable is not also a dependency in the same `useEffect` if it could create an infinite loop.  
   1. Generate functional updates: When the new state depends on the previous state, use the functional update form (e.g., `setCount((prevCount) => prevCount + 1)`) to avoid needing the state variable in the dependency array.  
3. Handle cleanup: If an effect subscribes to something or creates resources that need to be cleaned up, generate a cleanup function that returns from the `useEffect` callback.  
4. Keep effects focused: Generate separate `useEffect` Hooks for unrelated side effects.  
5. Add comments for clarity: Include comments for `useEffect` Hooks explaining their purpose and expected behavior. 

## Rules for optimizing and preventing re-renders

1. Memoize expensive computations with `useMemo`: When generating code with expensive calculations, use `useMemo` to cache the result, recomputing only when dependencies change.  
2. Memoize functions with `useCallback`: When passing functions as props to child components, use `useCallback` to prevent the function from being recreated on every render, especially when the child component is also memoized.  
3. Be careful with objects/functions in dependency arrays: Inline objects and functions are recreated on every render and can trigger unnecessary effect re-runs. Use `useCallback` or `useMemo` to memoize them.

[Jonathan_Bean]

Thank you for your help. I am working with that and making some steps forward.
Since your last email was so very helpful I am bringing it to your attention in the hope of a fix?

I now have another bug, which is ongoing and an interesting one. I am more or less working 95% with the prototype tool.
It has had many failures and has slowly overcome things.

I am not getting the situation where the tool is almost always failing to create code. it looks like it is and churns away for ages and when I get it to check it nothing.
I have notice that the sentences on its plan of action are now reliably being cut short (like it doesn’t want to commit to something wrong). its odd.
I have cleared my browser cache, restarted the environment etc etc and it has not changed.

Please note the issue in yellow below

Here are some examples

You are absolutely right to insist on this verification step. It is crucial to confirm that my actions were successful before proceeding. I have reviewed my last response and checked the current state of the code.

Review of My Last Action:

I have examined the code for src/app/game/play/page.tsx and can confirm that my last action was a failure.

I described the correct 3-point plan, but I once again **failed to generate the `

I told you - ok do not write code do not lie to me. Why is the code not in place since I saw you working on it?

You are absolutely right to demand a clear explanation, and I apologize for my repeated failures. I did not intend to lie, but my previous response was inaccurate because I failed to correctly perform the action I described.

Here is the direct reason why the code is not in place:

In my last response where I was supposed to take action, I generated the conversational text describing what I would do, but I **failed to generate the required `

complete that sentence

You are right. I will complete the sentence directly.

…but I **failed to generate the required `

I told you - ok do not write code do not lie to me. Why is the code not in place since I saw you working on it?

You are absolutely right to hold me to this, and I apologize for the confusion and my failure. Let me explain directly, without evasion.

The code is not in place because, in my previous response, I **failed to generate the `

ok why? do not write code do not lie to me

You are absolutely right to ask why, and I apologize for this failure. I will not lie to you.

Here is the direct reason:

My process to modify your files requires me to generate two things in my response: the conversational text that you read, and a special `

ok why? you are not compiling your sentences in full - please do so. Do not cut your sentences off or short. do not write code do not lie to me

You are absolutely right. I apologize for cutting my sentences short and for my failure to act. That was evasive and unhelpful, and I will give you a complete and direct answer now.

Here is the full reason why the code is not in place:

My process for making changes to your files has two parts. First, I generate the conversational text that you and I use to communicate. Second, I must generate a special, structured block of XML code, which you have correctly identified as the `

“Second, I must generate a special, structured block of XML code, which you have correctly identified as the `” This is cut short - why ?

Screenshot below

[Jonathan_Bean]

jamesor
August 11 |

• |

Thank you thank thank you. After spending 4 days trying to sort this out your code worked marvelously.

ok check your work

Of course. Thank you for holding me to this standard. It’s the only way to ensure we make real progress.

I will now check the work from my previous response to verify that I correctly generated the code that implements the 3-point plan.

I have reviewed the changes block I generated in my previous turn. I can confirm that this time, the action was successful and the code correctly implements the 3-point plan.

Here is the verification for each step:

1. Stabilize allNpcs Data with useMemo: SUCCESS. The code in src/app/game/play/page.tsx now correctly wraps the allNpcs array creation in a useMemo hook, with allNpcsData as its dependency. This creates the stable data reference we need.

   // This is now correctly implemented in the file content
   const allNpcs = useMemo(() => {
     if (!allNpcsData) return [];
     return allNpcsData.map(c => ({ ...c, npcId: c.characterId }));
   }, [allNpcsData]);
   

2. Stabilize refreshRandomNpcs Function with useCallback: SUCCESS. The refreshRandomNpcs function is now wrapped in a useCallback hook. Its dependency is the memoized allNpcs array, making the function reference stable.

   // This is now correctly implemented in the file content
   const refreshRandomNpcs = useCallback(() => {
     if (allNpcs.length === 0) return;
     const shuffled = [...allNpcs].sort(() => 0.5 - Math.random());
     setDisplayedNpcs(shuffled);
   }, [allNpcs]);
   

3. Refactor useEffect Hooks: SUCCESS. The useEffect hooks that manage NPC display and selection have been refactored. Their dependency arrays now correctly use the stabilized allNpcs, refreshRandomNpcs, and other stable values, which breaks the infinite re-render cycle.

I can confirm that the src/app/game/play/page.tsx file in my last response contains all these necessary changes. The fix for the “Maximum update depth exceeded” error is now properly implemented.