ESLint v7.0.0-alpha.0 released

Highlights

Most of the highlights of this release are breaking changes, and are discussed further in the migration guide.

In addition to the breaking changes, we have three new rules:

• default-case-last
• no-useless-backreference
• no-restricted-exports

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.0 --save-dev

Migration Guide

As there are a lot of changes, we’re working on 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

• 1aa021d Breaking: lint overrides files (fixes #10828, refs eslint/rfcs#20) (#12677) (Toru Nagashima)
• b50179d Breaking: Check assignment targets in no-extra-parens (#12490) (Milos Djermanovic)
• d86a5bb Breaking: Check flatMap in array-callback-return (fixes #12235) (#12765) (Milos Djermanovic)
• cf46df7 Breaking: description in directive comments (refs eslint/rfcs#33) (#12699) (Toru Nagashima)
• 7350589 Breaking: some rules recognize bigint literals (fixes #11803) (#12701) (Toru Nagashima)
• 1118fce Breaking: runtime-deprecation on ‘~/.eslintrc’ (refs eslint/rfcs#32) (#12678) (Toru Nagashima)
• 2c28fbb Breaking: drop Node.js 8 support (refs eslint/rfcs#44) (#12700) (Toru Nagashima)

Features

• f9774ec New: Add default-case-last rule (fixes #12665) (#12668) (Milos Djermanovic)
• a1d999c New: Add no-useless-backreference rule (fixes #12673) (#12690) (Milos Djermanovic)
• 985dac3 New: Add no-restricted-exports rule (fixes #10428) (#12546) (Milos Djermanovic)

Enhancements

• e59d775 Update: Separate pattern/expression options for array-element-newline (#11796) (jacobparish)
• f8f115a Update: treat comment tokens in template-curly-spacing (fixes #12744) (#12775) (YeonJuan)
• 9a93d9e Update: fix no-restricted-imports export * false negative (fixes #12737) (#12798) (Milos Djermanovic)
• 68becbd Update: fix no-restricted-imports importNames reporting (fixes #12282) (#12711) (Andrey Alexandrov)
• ae959b6 Update: report double extra parens in no-extra-parens (fixes #12127) (#12697) (YeonJuan)
• b2c6209 Update: fix no-extra-parens CallExpression#callee false negatives (#12743) (Milos Djermanovic)
• 14b42c3 Update: fix counting jsx comment len in max-len (fixes #12213) (#12661) (YeonJuan)
• 313f70a Update: add outerIIFEBody: “off” to indent rule (fixes #11377) (#12706) (Kai Cataldo)
• 3fa39a6 Update: Handle locally unsupported regex in computed property keys (#12056) (Milos Djermanovic)
• 8f1020f Update: no-void add an option to allow void as a statement (#12613) (Brad Zacher)
• bb6cf50 Update: Add offsetTernaryExpressions option for indent rule (#12556) (Adam Stankiewicz)

Bug Fixes

• de4fa7c Fix: wrong indent at tagged template in indent (fixes #12122) (#12596) (YeonJuan)
• 16a1c1f Fix: prefer-object-spread false positives with accessors (fixes #12086) (#12784) (Milos Djermanovic)
• 0d8c0af Fix: improve report location for computed-property-spacing (#12795) (Milos Djermanovic)
• 756b95d Fix: id-blacklist should ignore ObjectPatterns (fixes #12787) (#12792) (JP Ramassini)
• 01ff791 Fix: Display pipe character correctly in test output (#12771) (Brad Zacher)
• 00ddfff Fix: Windows path parsing for JUnit (fixes #12507) (#12509) (Michael Wall)
• 1aff21b Fix: no-mixed-spaces-and-tabs reports multiline strings (#12566) (Milos Djermanovic)

Documentation

• 02fcc05 Docs: Improve sort-keys (#12791) (Steven Vachon)
• 25eb703 Docs: fix dead link in max-lines rule docs (#12766) (Christian Bundy)
• 098b67d Docs: fix minor typo in brace-style.md (#12749) (Marko Kaznovac)
• b23ad0d Docs: change a broken link in working-with-rules.md (#12732) (Damien Cassou)

Dependency Upgrades

• e632c31 Upgrade: several dependencies (#12753) (Toru Nagashima)

Build Related

• 4e16957 Build: update browser build (#12693) (Toru Nagashima)
• 827259e Build: package.json update for eslint-config-eslint release (ESLint Jenkins)

Chores

• 561b6d4 Chore: add prerequisites checklist to PR template (#12790) (Kai Cataldo)
• 9dfc850 Chore: Refactor to use messageId in a number of rules (#12715) (Brad Zacher)
• b77b858 Chore: fix separateRequires tests for one-var rule (#12709) (Milos Djermanovic)
• e4df7df Chore: add JSDoc types for RuleTester test cases (#12325) (Chiawen Chen)
• 4744397 Chore: remove unused code in max-lines-per-function (#12659) (YeonJuan)
• 39f5a45 Chore: add test cases for for-direction (#12698) (YeonJuan)
• b340304 Chore: Add extra test, improve docs (#12492) (Kevin Partington)