ESLint couldn't determine the plugin "import" uniquely

[rtritto]

This issue, using yarn version >= 3.2.0-rc.7, is related to a conflict with 2 different ESLint config of eslint-plugin-import:

• eslint-config-next
• @ijsto/eslint-config » eslint-config-airbnb » eslint-config-airbnb-base

Steps to reproduce

1. yarn init -y
2. yarn set version canary (currently install yarn v3.2.0-rc.9)
3. yarn add @ijsto/eslint-config eslint eslint-config-next next react react-dom
4. Create .eslintrc.yml file :

extends:
  - '@ijsto'
  - next

5. Create an empty index.js file
6. Run 1 or both commands below

• yarn eslint index.js --> output:

Oops! Something went wrong! :(

ESLint: 8.4.1

ESLint couldn't determine the plugin "import" uniquely.

- C:\test-eslint\.yarn\__virtual__\eslint-plugin-import-virtual-2a929f9851\0\cache\eslint-plugin-import-npm-2.25.3-f5faefaae3-8bdf4b1faf.zip\node_modules\eslint-plugin-import\lib\index.js (loaded in ".eslintrc.yml » eslint-config-next")
- C:\test-eslint\.yarn\__virtual__\eslint-plugin-import-virtual-c11863593e\0\cache\eslint-plugin-import-npm-2.25.3-f5faefaae3-8bdf4b1faf.zip\node_modules\eslint-plugin-import\lib\index.js (loaded in ".eslintrc.yml » @ijsto/eslint-config » eslint-config-airbnb » C:\test-eslint\.yarn\__virtual__\eslint-config-airbnb-base-virtual-daa201a79f\0\cache\eslint-config-airbnb-base-npm-15.0.0-802837dd26-38626bad2c.zip\node_modules\eslint-config-airbnb-base\index.js » C:\test-eslint\.yarn\__virtual__\eslint-config-airbnb-base-virtual-daa201a79f\0\cache\eslint-config-airbnb-base-npm-15.0.0-802837dd26-38626bad2c.zip\node_modules\eslint-config-airbnb-base\rules\imports.js")

Please remove the "plugins" setting from either config or remove either plugin installation.

If you still can't figure out the problem, please stop by https://eslint.org/chat/help to chat with the team

• yarn next lint index.js --> output:

Error: Plugin "import" was conflicted between ".eslintrc.yml » eslint-config-next" and ".eslintrc.yml » @ijsto/eslint-config » eslint-config-airbnb » C:\test-eslint\.yarn\__virtual__\eslint-config-airbnb-base-virtual-daa201a79f\0\cache\eslint-config-airbnb-base-npm-15.0.0-802837dd26-38626bad2c.zip\node_modules\eslint-config-airbnb-base\index.js » C:\test-eslint\.yarn\__virtual__\eslint-config-airbnb-base-virtual-daa201a79f\0\cache\eslint-config-airbnb-base-npm-15.0.0-802837dd26-38626bad2c.zip\node_modules\eslint-config-airbnb-base\rules\imports.js"

[rtritto]

Conflict is generated because eslint-plugin-import is a dependency in:

• @ijsto/eslint-config (needed by peerDependencies of eslint-config-airbnb)
• eslint-config-next

Probably, a possible solution in @ijsto/eslint-config is to add eslint-config-next and to remove eslint-config-airbnb.

FYI

• Next.js ESLint:

  ... Next.js will automatically install eslint and eslint-config-next as development dependencies in your application ...

[ScottAgirs]

@rtritto interesting, thank you for providing these details! I wonder how would this work outside of a Next.js project.

[rtritto]

Some duplicated dependencies in eslint-config-next to remove in @ijsto/eslint-config (they should conflict after removing eslint-plugin-import):

• eslint-plugin-jsx-a11y
• eslint-plugin-react
• eslint-plugin-react-hooks

Another interesting feature, gained with eslint-config-next, is the import resolver of TypeScript (eslint-import-resolver-typescript).

[rtritto]

By this way, @ijsto/eslint-config must install all peerDependencies of eslint-config-next:

• next and (maybe) typescript from eslint-config-next
• react and react-dom from next

FYI

• Recommended Plugin Ruleset:

  If you already have ESLint configured in your application and any of the following conditions are true:
  You have one or more of the following plugins already installed (either separately or through a different config such as airbnb or react-app): react, react-hooks, jsx-a11y, import ...
  Then we recommend either removing these settings if you prefer how these properties have been configured within eslint-config-next or extending directly from the Next.js ESLint plugin instead: ...

• ESLint config:

  If you would like to use eslint-config-next along with other ESLint configurations, refer to the Additional Configurations section to learn how to do so without causing any conflicts.

---

Or, maybe, install and use only eslint-plugin-next instead of eslint-config-next; source:

• ESLint Plugin:

  Next.js provides an ESLint plugin, eslint-plugin-next...
  If you already have ESLint configured in your application, we recommend extending from this plugin directly instead of including eslint-config-next unless a few conditions are met. Refer to the Recommended Plugin Ruleset to learn more.