[eslint-patch] Upgrade to ESLint 9

[Nixie24]

ESLint v9.0.0 is released 🎉

It would be awesome to have official ESLint 9 support. 🙂

[iclanton]

I'm pretty sure there are a bunch of breaking changes in ESLint 9, so this may take some effort. If someone wants to take that on, we'd happily take it. For now, it'll be a lower priority for our team.

[kirill-konshin]

Even with recent fixup https://eslint.org/blog/2024/05/eslint-compatibility-utilities/ it fails:

Oops! Something went wrong! :(

ESLint: 9.2.0

Error: Failed to patch ESLint because the calling module was not recognized.
If you are using a newer ESLint version that may be unsupported, please create a GitHub issue:
https://github.com/microsoft/rushstack/issues
    at Object.<anonymous> (/xxx/node_modules/@rushstack/eslint-patch/lib/_patch-base.js:165:19)
    at Module._compile (node:internal/modules/cjs/loader:1375:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1434:10)
    at Module.load (node:internal/modules/cjs/loader:1206:32)
    at Module._load (node:internal/modules/cjs/loader:1022:12)
    at Module.require (node:internal/modules/cjs/loader:1234:19)
    at require (node:internal/modules/helpers:176:18)
    at Object.<anonymous> (/xxx/node_modules/@rushstack/eslint-patch/lib/modern-module-resolution.js:11:23)
    at Module._compile (node:internal/modules/cjs/loader:1375:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1434:10)

Just in case this helps...

The fixup works with configs (actual objects returned from config), and eslint-patch is usually called inside config. It might be useful to just disable some functionality if ESLint 9 is detected...

[kirill-konshin]

Thanks @nzakas for prompt response and fix. I assume we now have to wait for release and propagation to other packages like Next.js rules set?

[D4N14L]

@kirill-konshin yes. Publish is manually triggered. You can either choose to wait for the next publish, or you can request a publish from one of the senior maintainers.

[DmitryMarkov]

Even with recent fixup https://eslint.org/blog/2024/05/eslint-compatibility-utilities/ it fails:

Same for me

[kirill-konshin]

@D4N14L was it published? I'm getting the same error #4965 (comment) but with shareable config.

[D4N14L]

@kirill-konshin yes it is published, though I don't know if support for shareable configs requires any additional work. Could you share a repro?

[kirill-konshin]

@D4N14L sure, here you go: https://codesandbox.io/p/devbox/nqs2yk?file=%2Feslint.config.mjs

Just run yarn lint.

The problem is interference with newer Yarn it seems. Also I purposely made it a monorepo.

Here's with the Yarn 1: https://stackblitz.com/edit/stackblitz-starters-zxpfgk?file=eslint.config.mjs,package.json

It does not reproduce there directly, but if you download a zip and run

$ yarn set version berry
$ yarn
$ yarn lint

Then it will fail.

[kirill-konshin]

@D4N14L any chances to have this fixed? Can I help?

[D4N14L]

@kirill-konshin to be honest I don't think I'll be able to look any time soon. If you can create a fix or investigate a fix, that would be appreciated.

[kirill-konshin]

@D4N14L I don't really think I can, since the error originates from the module resolution patch and Yarn's nodeLinker: node-modules config.

BUT! On a positive side, I've just tested my custom config with Yarn's nodeLinker: pnpm (not pnp!) and it magically worked just fine.

So in addition to my reproduction scenario before, I can reliably say it works well with Yarn 1 and Yarn 2+ with nodeLinker: node-modules.

[D4N14L]

@kirill-konshin nice! So then seems possibly an issue with pnp compatibility in ESLint instead of anything that we have done. Glad to hear :)

[kirill-konshin]

@kirill-konshin nice! So then seems possibly an issue with pnp compatibility in ESLint instead of anything that we have done. Glad to hear :)

Not PNP but original node-modules linker...

[D4N14L]

Ah interesting. Then possibly an issue with shadow dependencies given that PNPM brings more dependency correctness with its algorithm