I recently updated to next 15, and haven't modified the 404 page.However, I'm getting this error for some reason while building the app ▲ Next.js 15.1.2 - Environments: .env Creating an optimized production build ... SyntaxError: Expected property name or '}' in JSON at position 182 at JSON.parse ( ) SyntaxError: Expected property name or '}' in JSON at position 182 at JSON.parse ( ) SyntaxError: Expected property name or '}' in JSON at position 182 at JSON.parse ( ) ✓ Compiled successfully ✓ Linting and checking validity of types SyntaxError: Expected property name or '}' in JSON at position 182 at JSON.parse ( ) ⚠ Using edge runtime on a page currently disables static generation for that page ✓ Collecting page data [TypeError: Cannot read properties of null (reading 'useContext')] Error occurred prerendering page "/404". Read more: https://nextjs.org/docs/messages/prerender-error TypeError: Cannot read properties of null (reading 'useContext')

I get this error only with turborepo: Error occurred prerendering page "/404"

Answered

Anay-208 | Ping on replies posted this in #help-forum

2024-12-25T12:20:02.091Z

I recently updated to next 15, and haven't modified the 404 page.

However, I'm getting this error for some reason while building the app

   ▲ Next.js 15.1.2
   - Environments: .env

   Creating an optimized production build ...
SyntaxError: Expected property name or '}' in JSON at position 182
    at JSON.parse (<anonymous>)
SyntaxError: Expected property name or '}' in JSON at position 182
    at JSON.parse (<anonymous>)
SyntaxError: Expected property name or '}' in JSON at position 182
    at JSON.parse (<anonymous>)
 ✓ Compiled successfully
 ✓ Linting and checking validity of types    
SyntaxError: Expected property name or '}' in JSON at position 182
    at JSON.parse (<anonymous>)
 ⚠ Using edge runtime on a page currently disables static generation for that page
 ✓ Collecting page data 
[TypeError: Cannot read properties of null (reading 'useContext')]
Error occurred prerendering page "/404". Read more: https://nextjs.org/docs/messages/prerender-error
TypeError: Cannot read properties of null (reading 'useContext')

Answered by Anay-208 | Ping on replies

https://github.com/vercel/turborepo/issues/9335
i found this, and this reply helped.

I just switched to pnpm after this, as I believe it'd be better for turborepo(and nextjs-forum, the bot is using it)

View full answer

24 Replies

Anay-208 | Ping on repliesOP

2024-12-25T12:20:16.826Z

I honestly don't know what to even send, however, I'm sending 404 file

https://gist.github.com/anay-208/f5218b3fd9989f701830eda8c4be815b

Anay-208 | Ping on repliesOP

2024-12-25T12:49:46.743Z

I've already checked the nextjs prerender page, which didn't help

Anay-208 | Ping on repliesOP

2024-12-25T13:35:09.110Z

Also tried deleting not-found.tsx

gin

2024-12-25T13:41:59.097Z

yes this is something that happened to me aswell when i migrated a app to next15

its not actually the 404 page itself

it just says that the error happened on 404 because while prerendering a dynamic route for example, and failing, nextjs will automatically reroute to a 404 and throw the error there

so what u can do is slowly check everywhere where u have dynamic data and use useContext

cause thats where the error is coming from

@gin so what u can do is slowly check everywhere where u have dynamic data and use useContext

Anay-208 | Ping on repliesOP

2024-12-25T13:46:49.285Z

I deleted all the routes where there is dynamic data. The error still persists

Anay-208 | Ping on repliesOP

2024-12-25T13:56:44.152Z

I tried it in another app, where I just have a hello world homepage. same error

Chub mackerel

2024-12-25T14:00:39.169Z

I guess there is should be a issue in your

.env/next.config.js

Anay-208 | Ping on repliesOP

2024-12-25T14:01:50.470Z

-# next.config.mjs

import { setupDevPlatform } from '@cloudflare/next-on-pages/next-dev';

// Here we use the @cloudflare/next-on-pages next-dev module to allow us to use bindings during local development
// (when running the application with `next dev`), for more information see:
// https://github.com/cloudflare/next-on-pages/blob/main/internal-packages/next-dev/README.md
if (process.env.NODE_ENV === 'development') {
  await setupDevPlatform();
}

// import type { NextConfig } from "next";

// const nextConfig: NextConfig = {
/** @type {import('next').NextConfig} */
const nextConfig = {
  /* config options here */
};

export default nextConfig;

I'll try removing setupDevPlatform & see

nope, still same error

Anay-208 | Ping on repliesOP

2024-12-25T16:17:23.426Z

So I also tried creating another app, where it works perfectly fine.

I used the exact same files from the old project(including package.json) in the new project, but I still get the error on old project.

I just want to find the cause for the error

Anay-208 | Ping on repliesOP

2024-12-25T16:27:50.473Z

So I found something interesting.

I basically have a turborepo, and I only get this error when I add that folder path to my workspaces in the repo root package.json

this was my repo root package.json:

{
  "name": "package",
  "scripts": {
    "migrate": "turbo run migrate"
  },
  "devDependencies": {
    "turbo": "^2.3.3"
  },
  "packageManager": "npm@8.5.0",
  "workspaces": [
    "apps/www",
    "packages/*"
  ]
}

Once I added apps/test, I started getting the error on that dir

Anay-208 | Ping on repliesOP

2024-12-25T17:27:02.961Z

Answer

@Anay-208 | Ping on replies https://github.com/vercel/turborepo/issues/9335 i found this, and this reply helped. I just switched to pnpm after this, as I believe it'd be better for turborepo(and nextjs-forum, the bot is using it)

gin

2024-12-26T08:15:55.966Z

oh yeah thats interesting

i had the same issues with turbopack aswell

cool that u found a solution

Anay-208 | Ping on repliesOP

2024-12-26T08:16:29.798Z

I was too lazy to solve this with npm so switched to pnpm