Update xo to the latest version 🚀

[greenkeeper[bot]]

Version 0.18.0 of xo just got published.

Dependency	xo
Current Version	0.17.1
Type	devDependency

The version 0.18.0 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of xo. Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Release Notes

0.18.0

Highlights

• The esnext option is now true by default. This means it now enforces the use of as much ES2015+ syntax as Node.js 4 supports. 61c046c
• 21 new rules:
  • Unicorn plugin: sindresorhus/eslint-plugin-unicorn@v1.0.0...v2.1.0
    • no-array-instanceof
    • no-new-buffer
    • no-hex-escape
    • number-literal-case
    • escape-case
    • prefer-starts-ends-with
    • custom-error-definition
    • type-error
  • AVA plugin: avajs/eslint-plugin-ava@a0156f1
    • no-async-fn-without-await
    • no-duplicate-modifiers
  • Promise plugin: 3e1a318
    • no-promise-in-callback
    • no-callback-in-promise
  • ESLint: sindresorhus/eslint-config-xo@v0.17.0...v0.18.0
    • func-name-matching
    • no-compare-neg-zero
    • template-tag-spacing
    • no-multi-assign
    • prefer-promise-reject-errors
    • no-await-in-loop
    • capitalized-comments
    • no-return-await
    • no-useless-return
• 27 additional ESLint rules are now auto-fixable with $ xo --fix.
• Handle negative gitignore patterns correctly. f8e1e3d
• Vim plugin for XO.
• Added --stdin-filename CLI flag. 0d88cde
• Added support for auto-fixing code from stdin. 6d6d642
• Added tip on how to use XO with monorepos. cb63c5f
• Removed the import/no-dynamic-require rule. 29a5263
• Ignores directories when receiving an empty extension. a0ae248
• Don't trigger import duplication errors for Flow type imports. da188e5

All changes

v0.17.1...v0.18.0

Commits

The new version differs by 19 commits .

• bf6260c 0.18.0
• 34ab00b Fix some lint issues
• f87990a Bump dependencies
• f8e1e3d Handle negative gitignore patterns correctly (#195)
• a0ae248 Ignore directories when receiving an empty extension (#194)
• da188e5 Don't trigger duplication errors for Flow type imports (#193)
• cb63c5f Add tip on how to use XO with monorepos
• 0d88cde Add --stdin-filename option
• 29a5263 Remove the import/no-dynamic-require rule
• a469eb6 Link to the Vim plugin
• 61c046c Make the esnext option true by default
• 2e14d1b feat: apply .ignores to lintText (#169)
• 3e1a318 Add some new eslint-plugin-promise rules
• ad941f5 Fix a TODO
• 6540a76 Add highlight item about caching

There are 19 commits in total. See the full diff.

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