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Sarj Code Standards

Unicorn

86 rules oxlint@1.91.0

Complete effective rule inventory.

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Rules

32 rules on this page · 86 total

  • unicorn/no-unnecessary-array-splice-count

    Disallow using .length or Infinity as the deleteCount or skipCount argument of Array#{splice,toSpliced}().

    : error in All Unicorn contexts
    Autofix available
  • unicorn/no-unnecessary-await

    Disallow awaiting non-promise values.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/no-unnecessary-slice-end

    Disallow using .length or Infinity as the end argument of {Array,String,TypedArray}#slice().

    : error in All Unicorn contexts
    Autofix available
  • unicorn/no-useless-collection-argument

    Disallow useless values or fallbacks in Set, Map, WeakSet, or WeakMap.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/no-useless-error-capture-stack-trace

    Disallow unnecessary Error.captureStackTrace(…).

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/no-useless-fallback-in-spread

    Disallow useless fallback when spreading in object literals.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/no-useless-iterator-to-array

    Disallow unnecessary .toArray() on iterators.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/no-useless-length-check

    Disallow useless array length check.

    : error in All Unicorn contexts
    No autofix
  • unicorn/no-useless-promise-resolve-reject

    Disallow returning/yielding Promise.resolve/reject() in async functions or promise callbacks

    : error in All Unicorn contexts
    Autofix available
  • unicorn/no-useless-spread

    Disallow unnecessary spread.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-add-event-listener

    Prefer .addEventListener() and .removeEventListener() over on-functions.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-array-flat

    Prefer Array#flat() over legacy techniques to flatten arrays.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-array-flat-map

    Prefer .flatMap(…) over .map(…).flat() and .filter(…).flatMap(…).

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-array-index-of

    Prefer Array#{indexOf,lastIndexOf}() over Array#{findIndex,findLastIndex}() when looking for the index of an item.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-array-some

    Prefer .some(…) over .filter(…).length check and .{find,findLast,findIndex,findLastIndex}(…).

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-at

    Prefer .at() method for index access and String#charAt().

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-bigint-literals

    Prefer BigInt literals over the constructor.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-blob-reading-methods

    Prefer Blob#arrayBuffer() over FileReader#readAsArrayBuffer(…) and Blob#text() over FileReader#readAsText(…).

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-class-fields

    Prefer class field declarations over this assignments in constructors.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-code-point

    Prefer String#codePointAt(…) over String#charCodeAt(…) and String.fromCodePoint(…) over String.fromCharCode(…).

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-date-now

    Prefer Date.now() to get the number of milliseconds since the Unix Epoch.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-default-parameters

    Prefer default parameters and destructuring defaults over reassignment and fallback expressions.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-event-target

    Prefer EventTarget over EventEmitter.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-export-from

    Prefer export…from when re-exporting.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-import-meta-properties

    Prefer import.meta.{dirname,filename} over legacy techniques for getting file paths.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-keyboard-event-key

    Prefer KeyboardEvent#key over deprecated keyboard event properties.

    : error in All Unicorn contexts
    Autofix available
  • unicorn/prefer-math-min-max

    Prefer Math.min() and Math.max() over ternaries for simple comparisons.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-math-trunc

    Prefer Math.trunc() for truncating numbers.

    : error in All Unicorn contexts
    Autofix available; suggestions available
  • unicorn/prefer-modern-math-apis

    Prefer modern Math APIs over legacy patterns.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-module

    Prefer JavaScript modules (ESM) over CommonJS.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-native-coercion-functions

    Prefer using String, Number, BigInt, Boolean, and Symbol directly.

    : error in All Unicorn contexts
    No autofix
  • unicorn/prefer-negative-index

    Prefer negative index over .length - index when possible.

    : error in All Unicorn contexts
    Autofix available