ESLint v2.4.0 released

by Nicholas C. Zakas - 11 March 2016

We just pushed ESLint v2.4.0, which is a minor release upgrade of ESLint. This release adds some new features and fixes several bugs found in the previous release.


This is a summary of the major changes you need to know about for this version of ESLint.

babel-eslint Compatibility Fix

The v2.3.0 release introduced a change that broke compatibility with babel-eslint. We realize that a lot of you depend on babel-eslint and so we wanted to make sure to restore compatibility as quickly as possible. We couldn't undo the change that cause the problem as it would have caused a regression for ESLint, and it took us some time to figure out the right approach to solve the problem.

With v2.4.0, babel-eslint compatibility is now restored with a permanent solution that should prevent this from happening again. We appreciate your patience as we tried to determine the best long-term solution.


  • 13ef1c7 New: add --parser-options to CLI (fixes #5495) (Jordan Harband)


  • 9c6c70c Update: add allowParens option to no-confusing-arrow (fixes #5332) (Burak Yigit Kaya)

Bug Fixes

  • 97b2466 Fix: estraverse/escope to work with unknowns (fixes #5476) (Nicholas C. Zakas)
  • 641b3f7 Fix: validate the type of severity level (fixes #5499) (Shinnosuke Watanabe)
  • 03e6869 Fix: newline-before-return: bug with comment (fixes #5480) (mustafa)
  • ad100fd Fix: overindent in VariableDeclarator parens or brackets (fixes #5492) (David Greenspan)
  • 9f18a81 Fix: Ignore destructuring assignment in object-shorthand (fixes #5488) (alberto)
  • 38eb7f1 Fix: key-spacing checks ObjectExpression is multiline (fixes #5479) (Kevin Partington)
  • 9592c45 Fix: no-unmodified-loop-condition false positive (fixes #5445) (Toru Nagashima)


  • 9ee8869 Docs: no-unused-expressions - add more edge unusable and usable examples (Brett Zamir)
  • 56bf864 Docs: Create parity between no-sequences examples (Brett Zamir)
  • ae1ee54 Docs: fix func-style arrow exception option (Craig Martin)
  • 91852fd Docs: no-lone-blocks - show non-problematic (and problematic) label (Brett Zamir)
  • b34458f Docs: Rearrange rules for better categories (and improve rule summaries) (Brett Zamir)
  • 1198b26 Docs: Minor README clarifications (Brett Zamir)
  • 9b8e04b Docs: Replace all node references to Node.js which is the official name (Brett Zamir)
  • cc1f2f0 Docs: Minor fixes in no-new-func (Brett Zamir)
  • 6ab81d4 Docs: Distinguish examples in rules under Best Practices part 1 (Mark Pedrotti)
  • 979c096 Docs: Document linebreak-style as fixable. (Afnan Fahim)
  • 5d9a798 Docs:, prefer-const; change modified to reassigned (Michiel de Bruijne)