`@docusaurus/eslint-plugin` is not compatible with ESLint 9

[Zamiell]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Description

See this dependency: https://github.com/facebook/docusaurus/blob/main/packages/eslint-plugin/package.json#L24

This needs to be upgraded to max, or else satisfying the peer deps is impossible on ESLint 9.

• I'd be willing to fix this bug myself.

[slorber]

Thanks

I didn't have time to study the problem, but is the change retro-compatible and can be done in a minor?

@Josh-Cena you probably have an idea?

[Josh-Cena]

I haven't updated a plugin to ESLint v9 so I don't know if that would suffice, but so I hope. Does flat config require a new recommended config format?

[Zamiell]

Not sure.

[Josh-Cena]

For now, let's include v9 in the peer dep range, and then people can try it out. Worst case they would need to apply workarounds like they already do with other plugins like plugin-react-hooks. Once I become more informed about how shared flat configs work, we can make it a new entry point like many other plugins are doing, and none of these changes would be semver breaking.

[PaulRBerg]

This is the workaround:

import pluginDocusaurus from "@docusaurus/eslint-plugin";

export default [
  // ...
  {
    plugins: {
      "@docusaurus": pluginDocusaurus,
    },
    rules: pluginDocusaurus.configs.recommended.rules,
  },
  // ...
];

Related thread: https://github.com/facebook/react/issues/28313

[Zamiell]

@Josh-Cena Bump - Any updates on this issue? Do you want me to just do a 1 line PR that updates the dep to latest?

[slorber]

If it's just a 1 line PR yes, but is it?

Sending a package.json PR is easy and has little value on its own unless you have a plan to validate that the change actually works with ESLint v9. I haven't really looked at ESLint 9 to know what should be done.

---

BTW what is the goal of that PR?

Afaik our deps already allow v9:

  "peerDependencies": {
    "eslint": ">=6"
  },

Have you encountered any problems with the workaround @PaulRBerg suggested?

[Zamiell]

The goal of the PR would be to squash the "peer requirements cannot be met" warning/error when running "npm install". For context, basically any modern ESLint setup can no longer use the Docusaurus plugin without getting the warning/error.

[slorber]

I see thanks,

The warning problem is due to "@typescript-eslint/utils": "^5.62.0",

ESLint v9 is only supported in peerDeps of utils v8:

https://github.com/typescript-eslint/typescript-eslint/blob/v8.0.0/packages/utils/package.json

But this also restricts the semver range of both ESLint and Node.js: we can't do that in Docusaurus v3, otherwise this might force plugin users to upgrade to ESLint >= 8 (we support >= 6) or Node.js >= 18.18 (we support >= 18.0)

Let's schedule the upgrade of this package to v4.