This upgrade is going to be a lot of work, because it brings a breaking change for plugins and our configuration. So we need to upgrade each and every plugin to a version that supports eslint v9, and then we will need to rewrite our configuration file to the new "flat config" format.
Here is a list of our plugins where maintainers have released versions compatible with v9:
eslint-plugin-you-dont-need-lodash-underscore
Upgrade: [] Support: ❌ https://github.com/you-dont-need/You-Dont-Need-Lodash-Underscore/issues/396
We could do the work to contribute the support for flat config & v9, or we could decide to drop this plugin. Usage of lodash has been drastically reduced.
=> We decided to drop this plugin. There are only a few remaining calls to lodash, and all of them are in old AngularJS apps. We expect to rework this code and use native alternatives during the migration out of AngularJS (see doc #1661).
eslint-plugin-monorepo-cop
Upgrade: [] Support: ❌ https://github.com/sterlingwes/eslint-plugin-monorepo-cop/issues/9
We could do the work to contribute the support for flat config & v9, or we need to find an alternative. We still want to forbid relative imports.
=> We decided to use a compatibility solution (see https://github.com/sterlingwes/eslint-plugin-monorepo-cop/issues/9). The plugin is still useful, we should contribute flat config support.
eslint-plugin-no-unsanitized
Upgrade: [x] Support: ☑ https://github.com/mozilla/eslint-plugin-no-unsanitized/commit/d9704a7e402c7f95e31b4f97a8c192afdcfe1994
Git diff for v4.0.2 -> v4.1.4
eslint-plugin-no-only-tests
Upgrade: [x] Support ☑
Release v3.3.0
eslint-plugin-storybook
Upgrade: [x] Support ☑ https://github.com/storybookjs/eslint-plugin-storybook/blob/v0.10.0/CHANGELOG.md#v0100-mon-oct-21-2024
Changelog for v0.12.0
eslint-plugin-jest
Upgrade: [x] Support ☑
eslint-plugin-import
Upgrade: [x] Support ☑ https://github.com/import-js/eslint-plugin-import/issues/2556
Changelog for v2.31.0
eslint-plugin-vue
Upgrade: [x] Support ☑ https://github.com/vuejs/eslint-plugin-vue/issues/1291
vue-eslint-parser
Upgrade: [x] Support: ☑ https://github.com/vuejs/vue-eslint-parser/releases/tag/v10.0.0
typescript-eslint
Upgrade: [x] Support ☑ https://github.com/typescript-eslint/typescript-eslint/issues/8211
eslint-plugin-cypress
Upgrade: [x] Support ☑ https://github.com/cypress-io/eslint-plugin-cypress/issues/146
eslint-plugin-prettier
Upgrade: [] Support ☑ https://github.com/prettier/eslint-plugin-prettier/issues/591
eslint
Upgrade: [x] 8.52.0 -> 8.57.0
Useful links: