v0.53.2

Compare Source

• Disable unicorn/require-array-sort-compare in favor of TS version for TS code (#​105) c67e766

v0.53.1

Compare Source

• Fix conflicting rules 6165417

v0.53.0

Compare Source

Breaking

• Require TypeScript 6

Prettier integration

A new prettier option lets you combine the rules with Prettier:

export default defineConfig([
	...eslintConfigXo({prettier: true}),
]);

• true — Runs Prettier as an ESLint rule using XO's Prettier style, and disables the stylistic rules that would conflict with it. Requires prettier to be installed.
• 'compat' — Only disables the stylistic rules that conflict with Prettier, for when you run Prettier separately (for example, from your editor).

Anything XO does not configure (like printWidth or Prettier plugins) still respects your .prettierrc, but XO's own style settings take precedence. prettier is an optional peer dependency.

CSS linting

.css files are now linted out of the box via @eslint/css: duplicate imports, empty blocks, invalid at-rules, unmatchable selectors, invalid named grid areas, and more.

New rules

• unicorn/better-dom-traversing
• unicorn/class-reference-in-static-methods
• unicorn/consistent-class-member-order
• unicorn/consistent-compound-words
• unicorn/consistent-export-decorator-position
• unicorn/consistent-json-file-read
• unicorn/consistent-optional-chaining
• unicorn/explicit-timer-delay
• unicorn/logical-assignment-operators
• unicorn/max-nested-calls
• unicorn/no-array-fill-with-reference-type
• unicorn/no-array-from-fill
• unicorn/no-array-splice
• unicorn/no-blob-to-file
• unicorn/no-break-in-nested-loop
• unicorn/no-canvas-to-image
• unicorn/no-computed-property-existence-check
• unicorn/no-confusing-array-splice
• unicorn/no-confusing-array-with
• unicorn/no-declarations-before-early-exit
• unicorn/no-duplicate-loops
• unicorn/no-duplicate-set-values
• unicorn/no-error-property-assignment
• unicorn/no-exports-in-scripts
• unicorn/no-global-object-property-assignment
• unicorn/no-incorrect-query-selector
• unicorn/no-incorrect-template-string-interpolation
• unicorn/no-late-current-target-access
• unicorn/no-mismatched-map-key
• unicorn/no-negated-array-predicate
• unicorn/no-negated-comparison
• unicorn/no-non-function-verb-prefix
• unicorn/no-object-methods-with-collections
• unicorn/no-optional-chaining-on-undeclared-variable
• unicorn/no-redundant-comparison
• unicorn/no-return-array-push
• unicorn/no-subtraction-comparison
• unicorn/no-top-level-side-effects
• unicorn/no-uncalled-method
• unicorn/no-undeclared-class-members
• unicorn/no-unnecessary-global-this
• unicorn/no-unnecessary-nested-ternary
• unicorn/no-unnecessary-splice
• unicorn/no-unreadable-object-destructuring
• unicorn/no-unsafe-buffer-conversion
• unicorn/no-unsafe-property-key
• unicorn/no-unsafe-string-replacement
• unicorn/no-unused-array-method-return
• unicorn/no-useless-boolean-cast
• unicorn/no-useless-coercion
• unicorn/no-useless-concat
• unicorn/no-useless-continue
• unicorn/no-useless-else
• unicorn/no-useless-override
• unicorn/no-useless-recursion
• unicorn/no-useless-template-literals
• unicorn/operator-assignment
• unicorn/prefer-add-event-listener-options
• unicorn/prefer-array-from-map
• unicorn/prefer-array-last-methods
• unicorn/prefer-array-slice
• unicorn/prefer-direct-iteration
• unicorn/prefer-early-return
• unicorn/prefer-else-if
• unicorn/prefer-get-or-insert-computed
• unicorn/prefer-global-number-constants
• unicorn/prefer-has-check
• unicorn/prefer-https
• unicorn/prefer-identifier-import-export-specifiers
• unicorn/prefer-includes-over-repeated-comparisons
• unicorn/prefer-iterable-in-constructor
• unicorn/prefer-iterator-to-array
• unicorn/prefer-iterator-to-array-at-end
• unicorn/prefer-location-assign
• unicorn/prefer-map-from-entries
• unicorn/prefer-math-abs
• unicorn/prefer-minimal-ternary
• unicorn/prefer-number-coercion
• unicorn/prefer-number-is-safe-integer
• unicorn/prefer-object-define-properties
• unicorn/prefer-object-destructuring-defaults
• unicorn/prefer-object-iterable-methods
• unicorn/prefer-path2d
• unicorn/prefer-private-class-fields
• unicorn/prefer-queue-microtask
• unicorn/prefer-scoped-selector
• unicorn/prefer-simple-sort-comparator
• unicorn/prefer-single-array-predicate
• unicorn/prefer-single-object-destructuring
• unicorn/prefer-smaller-scope
• unicorn/prefer-split-limit
• unicorn/prefer-string-match-all
• unicorn/prefer-string-pad-start-end
• unicorn/prefer-string-repeat
• unicorn/prefer-type-literal-last
• unicorn/prefer-uint8array-base64
• unicorn/prefer-unicode-code-point-escapes
• unicorn/prefer-url-href
• unicorn/require-array-sort-compare
• unicorn/require-css-escape
• unicorn/require-passive-events
• unicorn/require-proxy-trap-boolean-return
• @typescript-eslint/no-unnecessary-type-conversion

v0.52.0

Compare Source

Breaking

• Require Node.js 22 6b715f3

New rules

• @typescript-eslint/strict-boolean-expressions 0841559
• xo/import-specifier-newline 98f0aa9

Improvements

• Add eslint-plugin-jsdoc support ca9780b
• Add eslint-plugin-regexp support 2eba483
• Add Markdown support 2bb9c6c
• Add HTML support 5da39d4
• Make TypeScript optional for JavaScript-only projects 717184b
• Use eslint-import-resolver-typescript for import resolution 600b604
• naming-convention rule: Ignore all exotic/quoted keys bd171ba
• naming-convention rule: Allow UPPER_CASE for static readonly class properties ce92257
• naming-convention rule: Allow UPPER_CASE for module-level const variables 0b4bcce
• Add ?? to no-mixed-operators groups 9117295
• Require description for file-wide eslint-disable comments 55b6ae1
• Discourage npm packages with native alternatives 92549e8
• Remove deprecated rules 7e2747d
• Disable redundant ESLint rules for TypeScript files f474625
• capitalized-comments: Don't capitalize commented-out code aedc832

v0.51.0

Compare Source

Breaking

• The package now exports a function instead of an array. Update your eslint.config.js:

-export default eslintConfigXo;
+export default [...eslintConfigXo()];

• Removed the ./space and ./browser sub-path exports. Use the space and browser options instead:

export default [...eslintConfigXo({space: true, browser: true})];

• Requires ESLint 10 and Node.js 20.19+.

Improvements

• Merged eslint-config-xo-typescript: TypeScript rules are now included. No need to install a separate package.
• Merged plugin configs from XO: Includes eslint-plugin-unicorn, eslint-plugin-import-x, eslint-plugin-n, eslint-plugin-ava, @eslint-community/eslint-plugin-eslint-comments, and a built-in no-use-extend-native rule. Previously these were only available through the XO CLI.
• Added semicolon option
• Added TypeScript declaration file
• Add no-shadow rule 4cec7d2

v0.50.0

Compare Source

Breaking

• Require ESLint 10 874aefa

New rules

• preserve-caught-error 1e2cd5c
• require-unicode-regexp e9736c2
• css/no-unmatchable-selectors 7adc524
• css/no-duplicate-keyframe-selectors 8b3d031
• css/font-family-fallbacks adcb144

Improvements

• no-sequences: Add allowInParentheses: false 391d4c8

v0.49.0

Compare Source

Breaking

• Require Node.js 20 dd5cf67

New rules

• Add no-unused-private-class-members rule 568f75f
• Add css/no-invalid-at-rule-placement rule 8d122ab
• Add css/no-invalid-named-grid-areas rule 9f5d7c2

v0.48.0

Compare Source

• Add no-unassigned-vars rule 4082baa
• capitalized-comments: Support codespell (#​91) 3b196ad

v0.47.0

Compare Source

• capitalized-comments: Support biome ignore comments (#​90) 518f523
• Add @stylistic/curly-newline rule e1fe11c
• Add JSON plugin 6a547b5
• capitalized-comments: Add v8 to the ignorePattern option (#​88) 4bb2399

v0.46.0

Compare Source

New rules

• @stylistic/indent-binary-ops d91defd
• @stylistic/function-paren-newline fb5e204
• @stylistic/block-spacing cb6b443
• @stylistic/multiline-ternary 3dea281

Breaking

• Require Node.js 18.18
• Migrate to flat config and require ESLint 9 (#​86) ec210f2
  • Migrate config: https://eslint.org/docs/latest/use/configure/migration-guide

Improvements

• Migrate deprecated rules to @stylistic 0f81063
• Enable permissive max-len and max-lines as warning (#​84) e669d26
• Revert "Add option to no-extra-boolean-cast" (#​87) f010b63
• Add option to no-extra-boolean-cast a6dc171

v0.45.0

Compare Source

• Allow class fields with no blank lines between (#​85) 6f2ff13

v0.44.0

Compare Source

Breaking

• Require Node.js 18 f2060de

New rules

• logical-assignment-operators 27049c1
• prefer-object-has-own 288a3ca
• object-curly-newline (#​83) 3a5448b

Improvements

• Ban atob and btoa dfa969c
• Replace deprecated no-new-object rule 7f8f92e
• no-unused-vars: Allow ignoring variables by prefixing with underscore b31ab8a