This is just a quirk of how package.json exports work in conjunction with require.resolve (which ESLint itself uses under the hood):

> require('module').createRequire(path.join(process.cwd(), '_placeholder_.js')).resolve('@typescript-eslint/parser')
'/Users/bjz/temp/playground/node_modules/@typescript-eslint/parser/dist/index.js'

> require('module').createRequire(path.join(process.cwd(), '_placeholder_.js')).resolve(path.join(process.cwd(), 'node_modules', '@typescript-eslint/parser'))
Uncaught:
Error: Cannot find module '/Users/bjz/temp/playground/node_modules/@typescript-eslint/parser'
Require stack:
- /Users/bjz/temp/playground/_placeholder_.js
    at Module._resolveFilename (node:internal/modules/cjs/loader:1077:15)
    at Function.resolve (node:internal/modules/cjs/helpers:116:19) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [ '/Users/bjz/temp/playground/_placeholder_.js' ]
}

You will want to either use require.resolve('@typescript-eslint/parser') or you will want to just use '@typescript-eslint/parser' and rely on your --resolve-plugins-relative-to flag which will tell ESLint where to look.

you will want to just use '@typescript-eslint/parser' and rely on your --resolve-plugins-relative-to

I already use --resolve-plugins-relative-to - but this applies to "plugin" in the e.g. "extends" only. This does NOT apply to the parser.

You will want to either use require.resolve('@typescript-eslint/parser')

This doesn't work with a .json config obviously

This worked fine before 6.0.0, not sure how this is a user error?

This doesn't work with a .json config obviously

True! ESLint is moving away from .json configs: https://eslint.org/blog/2022/08/new-config-system-part-2/ -> https://eslint.org/docs/latest/use/configure/configuration-files-new. The new flat config will be particularly emphasized in ESLint 9: https://eslint.org/blog/2023/07/eslint-v8.45.0-released/#new-configuration-migration-guide. We're much less motivated to support them now. So hey, maybe this is a good excuse to switch over sooner? 😄

This worked fine before 6.0.0, not sure how this is a user error?

Before 6, you're right again - it would have been a bug. As of the changes described by https://typescript-eslint.io/blog/announcing-typescript-eslint-v6#package-exports, it's now intentional. We don't want to work against native Node/ESM import/require behaviors.

We're much less motivated to support them now. So hey, maybe this is a good excuse to switch over sooner? 😄

That's what I wanted to do, but it turns out @typescript-eslint isn't compatible with the new flat config yet.
While it's possible to make it work by manually importing all the rules (since the "extends" isn't supported anymore), it's kind of a waste of time to now change a .json to a .js and then eventually to the flat config.

But alas, that's what I'm doing now.

Got it - I meant to suggest just switching over to a .cjs/.js config now. But yeah, we're hoping to support flat configs soon (#6836).

Thanks for the conversation, by the way! This was very helpful in understanding a way we didn't previously know about how folks use us.

it's kind of a waste of time to now change a .json to a .js and then eventually to the flat config.

Note that the migration from .json to .js is this:

1. rename extension from .json to .js
2. update first line from { to module.exports = {

And that's it! JSON is valid JS so there are no further updates required to your config file (unless you have prettier or something which will want to format it...).

There's no difference in resolution or anything between the two config file types - so you can fearlessly make the switch now to improve your experience :)