ESlint error on build (even with starter template)

[SebastianSava]

Verify canary release

• I verified that the issue exists in Next.js canary release

Provide environment information

Operating System:        
  Platform: win32        
  Arch: x64
  Version: Windows 10 Pro
Binaries:
  Node: 16.13.1
  npm: 8.1.2
  Yarn: 1.22.15
  pnpm: 6.11.0
Relevant packages:
  next: 12.1.0
  react: 17.0.2
  react-dom: 17.0.2

What browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response

Describe the Bug

When i run npm run build

Expected Behavior

Build

To Reproduce

npm run build

[MoltenCoffee]

Just wanted to post the same issue! Experiencing this as well, both locally and GitHub Actions.

To further clarify:
Every instance in which a React component has children is marked as an array child without key by ESLint, including Next-buildins like next/head.

Windows 11 Education
Node v16.13.0
NPM 8.2.0

Ubuntu 20.04.3 (Github CI)
Node 16.14.0

Turning off reactStrictMode in next.config.(m)js does not help.

[wlee221]

This is a regression from eslint-plugin-react: jsx-eslint/eslint-plugin-react#3215

[timneutkens]

Handled in #34800

[SebastianSava]

How long it does it take to commit this canary to stable version? I ask because on npx create-next-app@latest is still broken. @timneutkens

[balazsorban44]

Already in canary https://github.com/vercel/next.js/releases/tag/v12.1.1-canary.3

latest will follow some time after.

[psudocode]

temporary fix

jsx-eslint/eslint-plugin-react#3215 (comment)

[jukialen]

I have v12.1.1-canary.3 but I still have that errors. I updated eslint-config-next to latest stable and 12.1.1-canary.3.

[github-actions]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.