Bug: `package.json` `eslintConfig` no longer functions about eslint

[ryanblock]

@Rec0iL99 thanks for clarifying this. For the record, in the blog post you mentioned, there is no specific mention of decision to remove support for the eslintConfig package.json property. So while I understand and accept that this method of configuration is no longer supported in v9, I would kindly suggest reopening this issue in service of improving the documentation around package.json eslintConfig. Thanks!

[nzakas]

Working on this.

[nzakas]

Yeah, we did apparently skip over mentioning package.json. We should definitely add that to the migration guide.

[Rec0iL99]

Hi @ryanblock, thanks for the issue. The .eslintrc config system is now deprecated and the flat config system is the new default config system in ESLint from v9.0.0. The eslintConfig field in package.json is no longer supported in the flat config system.

If you want to continue using eslintConfig (.eslintrc config system) in package.json, then you must set the environment variable ESLINT_USE_FLAT_CONFIG to false.

The decision to remove support for eslintConfig field was mentioned in this blog post.

I would recommend reading this blog series on flat config.

https://eslint.org/blog/2022/08/new-config-system-part-1/
https://eslint.org/blog/2022/08/new-config-system-part-2/
https://eslint.org/blog/2022/08/new-config-system-part-3/

[Rec0iL99]

Sure, I guess we could include this in the migration guide.

ping @eslint/eslint-team

[aladdin-add]

It's more of a documentation improvement. PRs are welcome! 👍