Upgrade eslint to V9 and typescript-eslint v7

[tianyingchun]

upgrade eslint typescript to https://typescript-eslint.io/blog/announcing-typescript-eslint-v7

[belgattitude]

Thanks @tianyingchun It's actually updated, see https://github.com/belgattitude/nextjs-monorepo-example/blob/main/packages/eslint-config-bases/package.json

But be aware than it might cause issues, I'm tracking it down in an another repo belgattitude/shared-dx#539

The idea is to first allow https://github.com/vercel/next.js/blob/dd24033caf1cfcfc3f9efde925bf54132e4d322c/packages/eslint-config-next/package.json#L15C35-L15C51

[tianyingchun]

we don't use typescript-eslint package directly?

[belgattitude]

I think this will answer your question

• issue Compatibility issue with typescript eslint v7  vercel/next.js#62138
• pr - eslint-config-next: allow typescript eslint v7 vercel/next.js#62137

[tianyingchun]

typescript-eslint has dependencies

  "dependencies": {
    "@typescript-eslint/eslint-plugin": "7.0.1",
    "@typescript-eslint/parser": "7.0.1"
  },

https://github.com/typescript-eslint/typescript-eslint/blob/main/packages/typescript-eslint/package.json#L56

[belgattitude]

Yes... you're well talking about this repo ?

it's on v7:

nextjs-monorepo-example/packages/eslint-config-bases/package.json

Line 70 in 091ae3b

"@typescript-eslint/eslint-plugin": "^7.0.0",

The warning I mentionned is that it will cause issues till other plugins allows it at v7 too. See above.

Would suggest to play with yarn why -R @typescript-eslint/parser to understand the side-effects. A major must be allowed by all other plugins, otherwise the hoisting will possibly lead to eslint 'cannot ... uniquely'... this won't happens with eslint flat config, but not yet ready in the ecosystem

[tianyingchun]

yes, agree :) maybe we need to wait the eslint related plugins upgrade to support V7

[tianyingchun]

eslint V9 now released, will eslint-config-bases updated ?

[belgattitude]

I’ll wait till nextjs supports it. Feel free to open a pr too. Might help to discover issues as well.

[belgattitude]

Btw the pr vercel/next.js#62137 landed in nextjs 14.2.0

[belgattitude]

To keep reference:

• Latest eslint-plugin-react-hooks partially support eslint v9 (no flat config yet) in eslint-plugin-react-hooks: Add support for ESLint v9 facebook/react#28773. Released in v4.6.2. Changelog not clear enough to see if it can replace the 5-canary required by nextjs plugin (TBD)
• Nextjs eslint plugin, does not yet support v9. (keep track in nextjs issues) : "eslint-plugin-react-hooks": "^4.5.0 || 5.0.0-canary-7118f5dd7-20230705" in https://github.com/vercel/next.js/blob/canary/packages/eslint-config-next/package.json

[tianyingchun]

waiting few month later maybe :)

[tianyingchun]

https://github.com/ArnaudBarre/eslint-plugin-react-refresh
if we need to include eslint-plugin-react-refresh