ESLint v8.0.0-beta.1 released

Highlights

• Beta testing revealed that the impact of the breaking change to allow line comment directives for all directives that previously required block comments outweighs the benefits of this feature due to a high number of accidental directives, so we decided to revert this change and exclude this feature from v8.0.0.
• Code Path Analysis now supports ES2022 class fields. In particular, each class field initializer now starts a separate code path. A new origin property has been added to CodePath objects.
• The meta.docs.category property has been removed from all core rules.

Since this is a beta release, it is not expected to be ready for production, but please try it and report any unexpected issues.

Installing

Since this is a pre-release version, you will not automatically be upgraded by npm. You must specify the next tag when installing:

npm i eslint@next --save-dev

You can also specify the version directly:

npm i eslint@8.0.0-beta.1 --save-dev

Migration Guide

As there are a lot of changes, we’ve created a migration guide describing the changes in great detail along with the steps you should take to address them. We expect that most users should be able to upgrade without any build changes, but the migration guide should be a useful resource if you encounter problems.

Breaking Changes

• 305e14a Breaking: remove meta.docs.category in core rules (fixes #13398) (#14594) (薛定谔的猫)

Enhancements

• 05ca24c Update: Code path analysis for class fields (fixes #14343) (#14886) (Nicholas C. Zakas)
• 44c6fc8 Update: support class fields in func-name-matching (refs #14857) (#14964) (Milos Djermanovic)
• 3d7d5fb Update: reporting loc for never option in eol-last (refs #12334) (#14840) (Nitin Kumar)
• f110926 Update: fix no-unused-vars false negative with comma operator (#14928) (Sachin)
• 26b0cd9 Update: fix no-unreachable logic for class fields (refs #14857) (#14920) (Milos Djermanovic)

Bug Fixes

• 3409785 Fix: camelcase ignoreGlobals shouldn’t apply to undef vars (refs #14857) (#14966) (Milos Djermanovic)
• ee1b54f Fix: keyword-spacing private name compat (refs #14857) (#14946) (Nicholas C. Zakas)

Documentation

• 396a0e3 Docs: update ScopeManager with class fields (#14974) (Milos Djermanovic)
• 6663e7a Docs: remove docs script (fixes #14288) (#14971) (Nitin Kumar)
• 44f7de5 Docs: Update deprecated information (#14961) (TagawaHirotaka)
• a8bcef7 Docs: Add 2021 and 2022 to supported ECMAScript versions (#14952) (coderaiser)
• b301069 Docs: fix ‘When Not To Use’ in prefer-named-capture-group (refs #14959) (#14969) (Milos Djermanovic)
• e98f14d Docs: Fix typo in no-implicit-globals.md (#14954) (jwbth)
• 81c60f4 Docs: document ESLint api (#14934) (Sam Chen)

Build Related

• c74fe08 Build: Force prerelease peer dep for Node 16 in CI (#14933) (Brandon Mills)

Chores

• db15183 Chore: Refactor comments of tests (#14956) (TagawaHirotaka)
• a79c9f3 Chore: Enforce jsdoc check-line-alignment never (#14955) (Brett Zamir)
• 2d18db6 Chore: add test for merging parserOptions in Linter (#14948) (Milos Djermanovic)
• 9a4ae3b Chore: Apply comment require-description and check ClassDeclaration (#14949) (Brett Zamir)
• 8344675 Chore: fix small typo (#14951) (Sosuke Suzuki)
• 58840ac Chore: Update jsdoc plugin and tweak rules in effect (#14814) (Brett Zamir)