ESLint v7.0.0-alpha.2 released

Highlights

This release contains the following breaking changes:

1. Updating default configuration options in core rules.
2. Updating the rules recommended in eslint:recommended.
3. Making RuleTester checks stricter.

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@7.0.0-alpha.2 --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

• 4af06fc Breaking: Test with an unknown error property should fail in RuleTester (#12096) (Milos Djermanovic)
• afa9aac Breaking: class default true computed-property-spacing (fixes #12812) (#12915) (Milos Djermanovic)
• 7d52151 Breaking: classes default true in accessor-pairs (fixes #12811) (#12919) (Milos Djermanovic)
• 78182e4 Breaking: Add new rules to eslint:recommended (fixes #12911) (#12920) (Milos Djermanovic)
• 6423e11 Breaking: check unnamed default export in func-names (fixes #12194) (#12195) (Chiawen Chen)

Enhancements

• a5b41a7 Update: no-restricted-modules handle TemplateLiteral (fixes #12926) (#12927) (Michal Piechowiak)
• 051567a Update: check identifier in array pattern in id-length (fixes #12832) (#12839) (YeonJuan)
• 9038a29 Update: func-names as-needed false negative with AssignmentPattern (#12932) (Milos Djermanovic)
• 7747177 Update: report rename id destructuring in id-blacklist (fixes #12807) (#12923) (YeonJuan)
• 77df505 Update: check renaming identifier in object destructuring (fixes 12827) (#12881) (YeonJuan)
• 41de9df Update: enforceForLogicalOperands no-extra-boolean-cast (fixes #12137) (#12734) (jmoore914)

Bug Fixes

• afde78b Fix: curly removes necessary braces between if and else (fixes #12928) (#12943) (Milos Djermanovic)
• 4797fb2 Fix: arrow-body-style crash with object literal body (fixes #12884) (#12886) (Milos Djermanovic)
• de14d1c Fix: wrap-iife autofix removes mandatory parentheses (#12905) (Milos Djermanovic)
• 5775b06 Fix: Optionally allow underscores in member names (#11972) (Edgardo Avilés)
• 0dfc3ff Fix: add end location to report in no-eval (#12960) (Milos Djermanovic)

Documentation

• b8e20d3 Docs: Mention TypeScript’s compiler check (#12903) (Benny Neugebauer)
• e997f32 Docs: Updated arrow-parens for minor grammar issue (#12962) (Tom)
• cf14355 Docs: Fix links to custom parsers doc (#12965) (Brandon Mills)
• f479f6f Docs: References correct config file name (#12885) (Patrick Kilgore)
• 8d5c434 Docs: fix category descriptions for site generation (fixes #12894) (#12930) (Kai Cataldo)
• 05380e6 Docs: Remove claim about semicolons from docs (#12944) (Luke Sikina)