JavaScript

✔ — Part of eslint:recommended
🛠 — Can be fixed automatically with --fix
🔴 — Enabled as an error
🟡 — Enabled as a warning
ⓧ — Disabled

Errors

Rec	Fix	Status	Rule	Description
✔		🔴	for-direction	enforce "for" loop update clause moving the counter in the right direction.
✔		🔴	getter-return	enforce `return` statements in getters
✔		🔴	no-async-promise-executor	disallow using an async function as a Promise executor
		🔴	no-await-in-loop	disallow `await` inside of loops
✔		🔴	no-compare-neg-zero	disallow comparing against -0
✔		🔴	no-cond-assign	disallow assignment operators in conditional expressions
		🔴	no-console	disallow the use of `console` `allow: ['error', 'warn']`
✔		🔴	no-constant-condition	disallow constant expressions in conditions
✔		🔴	no-control-regex	disallow control characters in regular expressions
✔		🔴	no-debugger	disallow the use of `debugger`
✔		🔴	no-dupe-args	disallow duplicate arguments in `function` definitions
✔		🔴	no-dupe-else-if	disallow duplicate conditions in if-else-if chains
✔		🔴	no-dupe-keys	disallow duplicate keys in object literals
✔		🔴	no-duplicate-case	disallow duplicate case labels
✔		🔴	no-empty	disallow empty block statements
✔		🔴	no-empty-character-class	disallow empty character classes in regular expressions
✔		🔴	no-ex-assign	disallow reassigning exceptions in `catch` clauses
✔	🛠	🔴	no-extra-boolean-cast	disallow unnecessary boolean casts
	🛠	🔴	no-extra-parens	disallow unnecessary parentheses
✔	🛠	🔴	no-extra-semi	disallow unnecessary semicolons
✔		🔴	no-func-assign	disallow reassigning `function` declarations
✔		🔴	no-import-assign	disallow assigning to imported bindings
✔		🔴	no-inner-declarations	disallow variable or `function` declarations in nested blocks
✔		🔴	no-invalid-regexp	disallow invalid regular expression strings in `RegExp` constructors
✔		🔴	no-irregular-whitespace	disallow irregular whitespace
		🔴	no-loss-of-precision	disallow literal numbers that lose precision
✔		🔴	no-misleading-character-class	disallow characters which are made with multiple code points in character class syntax
✔		🔴	no-obj-calls	disallow calling global object properties as functions
		🔴	no-promise-executor-return	disallow returning values from Promise executor functions
✔		🔴	no-prototype-builtins	disallow calling some `Object.prototype` methods directly on objects
✔	🛠	🔴	no-regex-spaces	disallow multiple spaces in regular expressions
✔		🔴	no-setter-return	disallow returning values from setters
✔		🔴	no-sparse-arrays	disallow sparse arrays
		🔴	no-template-curly-in-string	disallow template literal placeholder syntax in regular strings
✔		🔴	no-unexpected-multiline	disallow confusing multiline expressions
✔		🔴	no-unreachable	disallow unreachable code after `return`, `throw`, `continue`, and `break` statements
		🔴	no-unreachable-loop	disallow loops with a body that allows only one iteration
✔		🔴	no-unsafe-finally	disallow control flow statements in `finally` blocks
✔		🔴	no-unsafe-negation	disallow negating the left operand of relational operators
		🔴	no-useless-backreference	disallow useless backreferences in regular expressions
		ⓧ	require-atomic-updates	disallow assignments that can lead to race conditions due to usage of `await` or `yield`
✔		🔴	use-isnan	require calls to `isNaN()` when checking for `NaN`
✔		🔴	valid-typeof	enforce comparing `typeof` expressions against valid strings `requireStringLiterals: true`

Best Practices

Rec	Fix	Status	Rule	Description
		🟡	accessor-pairs	enforce getter and setter pairs in objects and classes setWithoutGet: true getWithoutSet: false enforceForClassMembers: true
		🔴	array-callback-return	enforce `return` statements in callbacks of array methods
		🔴	block-scoped-var	enforce the use of variables within the scope they are defined
		ⓧ	class-methods-use-this	enforce that class methods utilize `this`
		ⓧ	complexity	enforce a maximum cyclomatic complexity allowed in a program
		🔴	consistent-return	require `return` statements to either always or never specify values
	🛠	🔴	curly	enforce consistent brace style for all control statements `multi-line`
		ⓧ	default-case	require `default` cases in `switch` statements
		🔴	default-case-last	enforce default clauses in switch statements to be last
		🔴	default-param-last	enforce default parameters to be last
	🛠	🔴	dot-location	enforce consistent newlines before and after dots `property`
	🛠	🔴	dot-notation	enforce dot notation whenever possible `allowKeywords: true`
	🛠	🔴	eqeqeq	require the use of `===` and `!==` `always` `null: 'ignore'`
		🔴	grouped-accessor-pairs	require grouped accessor pairs in object literals and classes
		🔴	guard-for-in	require `for-in` loops to include an `if` statement
		🔴	max-classes-per-file	enforce a single class per file
		🔴	no-alert	disallow the use of `alert`, `confirm`, and `prompt`
		🔴	no-caller	disallow the use of `arguments.caller` or `arguments.callee`
✔		🔴	no-case-declarations	disallow lexical declarations in case clauses
		🔴	no-constructor-return	disallow returning value from constructor
	🛠	ⓧ	no-div-regex	disallow division operators explicitly at the beginning of regular expressions
	🛠	🔴	no-else-return	disallow `else` blocks after `return` statements in `if` statements
		🔴	no-empty-function	disallow empty functions `allow: ['arrowFunctions', 'functions', 'methods']`
✔		🔴	no-empty-pattern	disallow empty destructuring patterns
		ⓧ	no-eq-null	disallow `null` comparisons without type-checking operators
		🔴	no-eval	disallow the use of `eval()`
		🔴	no-extend-native	disallow extending native types
	🛠	🔴	no-extra-bind	disallow unnecessary calls to `.bind()`
	🛠	🔴	no-extra-label	disallow unnecessary labels
✔		🔴	no-fallthrough	disallow fallthrough of `case` statements
	🛠	🔴	no-floating-decimal	disallow leading or trailing decimal points in numeric literals
✔		🔴	no-global-assign	disallow assignments to native objects or read-only global variables
	🛠	ⓧ	no-implicit-coercion	disallow shorthand type conversions
		ⓧ	no-implicit-globals	disallow declarations in the global scope
		🔴	no-implied-eval	disallow the use of `eval()`-like methods
		ⓧ	no-invalid-this	disallow `this` keywords outside of classes or class-like objects
		🔴	no-iterator	disallow the use of the `__iterator__` property
		🔴	no-labels	disallow labeled statements `allowLoop: false` `allowSwitch: false`
		🔴	no-lone-blocks	disallow unnecessary nested blocks
		🔴	no-loop-func	disallow function declarations that contain unsafe references inside loop statements
		🔴	no-magic-numbers	disallow magic numbers `ignoreArrayIndexes: false` `enforceConst: true` `detectObjects: false
	🛠	🔴	no-multi-spaces	disallow multiple spaces
		🔴	no-multi-str	disallow multiline strings
		🔴	no-new	disallow `new` operators outside of assignments or comparisons
		🔴	no-new-func	disallow `new` operators with the `Function` object
		🔴	no-new-wrappers	disallow `new` operators with the `String`, `Number`, and `Boolean` objects
✔		🔴	no-octal	disallow octal literals
		🔴	no-octal-escape	disallow octal escape sequences in string literals
		🔴	no-param-reassign	disallow reassigning `function` parameters `props: true` `ignorePropertyModificationsFor`...
		🔴	no-proto	disallow the use of the `__proto__` property
✔		🔴	no-redeclare	disallow variable redeclaration
		🔴	no-restricted-properties	disallow certain properties on certain objects
		🔴	no-return-assign	disallow assignment operators in `return` statements
		🔴	no-return-await	disallow unnecessary `return await`
		🔴	no-script-url	disallow `javascript:` urls
✔		🔴	no-self-assign	disallow assignments where both sides are exactly the same
		🔴	no-self-compare	disallow comparisons where both sides are exactly the same
		🔴	no-sequences	disallow comma operators
		🔴	no-throw-literal	disallow throwing literals as exceptions
		ⓧ	no-unmodified-loop-condition	disallow unmodified loop conditions
		🔴	no-unused-expressions	disallow unused expressions `allowShortCircuit: false` `allowTernary: false` `allowTaggedTemplates: false`
✔	🛠	🔴	no-unused-labels	disallow unused labels
		🔴	no-useless-call	disallow unnecessary calls to `.call()` and `.apply()`
✔		🔴	no-useless-catch	disallow unnecessary `catch` clauses
		🔴	no-useless-concat	disallow unnecessary concatenation of literals or template literals
✔		🔴	no-useless-escape	disallow unnecessary escape characters
	🛠	🔴	no-useless-return	disallow redundant return statements
		🔴	no-void	disallow `void` operators
		🔴	no-warning-comments	disallow specified warning terms in comments `terms: ['todo', 'fixme', 'error', '?']` `location: 'start'`
✔		🔴	no-with	disallow `with` statements
		🟡	prefer-named-capture-group	enforce using named capture group in regular expression
		🔴	prefer-promise-reject-errors	require using Error objects as Promise rejection reasons `allowEmptyReject: true`
		🔴	prefer-regex-literals	disallow use of the `RegExp` constructor in favor of regular expression literals `disallowRedundantWrapping: true`
		🔴	radix	enforce the consistent use of the radix argument when using `parseInt()` `'as-needed': true`
		ⓧ	require-await	disallow async functions which have no `await` expression
		ⓧ	require-unicode-regexp	enforce the use of `u` flag on RegExp
		🔴	vars-on-top	require `var` declarations be placed at the top of their containing scope
	🛠	🔴	wrap-iife	require parentheses around immediate `function` invocations `inside` `functionPrototypeMethods: false`
	🛠	🟡	yoda	require or disallow "Yoda" conditions

Strict mode

Rec	Fix	Status	Rule	Description
	🛠		strict	require or disallow strict mode directives

Variables

Rec	Fix	Rule	Description
		init-declarations	require or disallow initialization in variable declarations
✔		no-delete-var	disallow deleting variables
		no-label-var	disallow labels that share a name with a variable
		no-restricted-globals	disallow specified global variables
		no-shadow	disallow variable declarations from shadowing variables declared in the outer scope
✔		no-shadow-restricted-names	disallow identifiers from shadowing restricted names
✔		no-undef	disallow the use of undeclared variables unless mentioned in `/global /` comments
	🛠	no-undef-init	disallow initializing variables to `undefined`
		no-undefined	disallow the use of `undefined` as an identifier
✔		no-unused-vars	disallow unused variables
		no-use-before-define	disallow the use of variables before they are defined

Style

Rec	Fix	Status	Rule	Description
	🛠		array-bracket-newline	enforce linebreaks after opening and before closing array brackets
	🛠		array-bracket-spacing	enforce consistent spacing inside array brackets
	🛠		array-element-newline	enforce line breaks after each array element
	🛠		block-spacing	disallow or enforce spaces inside of blocks after opening block and before closing block
	🛠		brace-style	enforce consistent brace style for blocks
			camelcase	enforce camelcase naming convention
	🛠		capitalized-comments	enforce or disallow capitalization of the first letter of a comment
	🛠	🔴	comma-dangle	require or disallow trailing commas
	🛠		comma-spacing	enforce consistent spacing before and after commas
	🛠		comma-style	enforce consistent comma style
	🛠		computed-property-spacing	enforce consistent spacing inside computed property brackets
			consistent-this	enforce consistent naming when capturing the current execution context
	🛠		eol-last	require or disallow newline at the end of files
	🛠		func-call-spacing	require or disallow spacing between function identifiers and their invocations
			func-name-matching	require function names to match the name of the variable or property to which they are assigned
			func-names	require or disallow named `function` expressions
			func-style	enforce the consistent use of either `function` declarations or expressions
	🛠		function-call-argument-newline	enforce line breaks between arguments of a function call
	🛠		function-paren-newline	enforce consistent line breaks inside function parentheses
			id-denylist	disallow specified identifiers
			id-length	enforce minimum and maximum identifier lengths
			id-match	require identifiers to match a specified regular expression
	🛠		implicit-arrow-linebreak	enforce the location of arrow function bodies
	🛠		indent	enforce consistent indentation
	🛠		jsx-quotes	enforce the consistent use of either double or single quotes in JSX attributes
	🛠		key-spacing	enforce consistent spacing between keys and values in object literal properties
	🛠		keyword-spacing	enforce consistent spacing before and after keywords
			line-comment-position	enforce position of line comments
	🛠		linebreak-style	enforce consistent linebreak style
	🛠		lines-around-comment	require empty lines around comments
	🛠		lines-between-class-members	require or disallow an empty line between class members
			max-depth	enforce a maximum depth that blocks can be nested
			max-len	enforce a maximum line length
			max-lines	enforce a maximum number of lines per file
			max-lines-per-function	enforce a maximum number of line of code in a function
			max-nested-callbacks	enforce a maximum depth that callbacks can be nested
			max-params	enforce a maximum number of parameters in function definitions
			max-statements	enforce a maximum number of statements allowed in function blocks
			max-statements-per-line	enforce a maximum number of statements allowed per line
	🛠		multiline-comment-style	enforce a particular style for multiline comments
			multiline-ternary	enforce newlines between operands of ternary expressions
			new-cap	require constructor names to begin with a capital letter
	🛠		new-parens	enforce or disallow parentheses when invoking a constructor with no arguments
	🛠		newline-per-chained-call	require a newline after each call in a method chain
			no-array-constructor	disallow `Array` constructors
			no-bitwise	disallow bitwise operators
			no-continue	disallow `continue` statements
			no-inline-comments	disallow inline comments after code
	🛠		no-lonely-if	disallow `if` statements as the only statement in `else` blocks
			no-mixed-operators	disallow mixed binary operators
✔			no-mixed-spaces-and-tabs	disallow mixed spaces and tabs for indentation
			no-multi-assign	disallow use of chained assignment expressions
	🛠		no-multiple-empty-lines	disallow multiple empty lines
			no-negated-condition	disallow negated conditions
			no-nested-ternary	disallow nested ternary expressions
			no-new-object	disallow `Object` constructors
			no-plusplus	disallow the unary operators `++` and `--`
			no-restricted-syntax	disallow specified syntax
			no-tabs	disallow all tabs
			no-ternary	disallow ternary operators
	🛠		no-trailing-spaces	disallow trailing whitespace at the end of lines
			no-underscore-dangle	disallow dangling underscores in identifiers
	🛠		no-unneeded-ternary	disallow ternary operators when simpler alternatives exist
	🛠		no-whitespace-before-property	disallow whitespace before properties
	🛠		nonblock-statement-body-position	enforce the location of single-line statements
	🛠		object-curly-newline	enforce consistent line breaks inside braces
	🛠		object-curly-spacing	enforce consistent spacing inside braces
	🛠		object-property-newline	enforce placing object properties on separate lines
	🛠		one-var	enforce variables to be declared either together or separately in functions
	🛠		one-var-declaration-per-line	require or disallow newlines around variable declarations
	🛠		operator-assignment	require or disallow assignment operator shorthand where possible
	🛠		operator-linebreak	enforce consistent linebreak style for operators
	🛠		padded-blocks	require or disallow padding within blocks
	🛠		padding-line-between-statements	require or disallow padding lines between statements
	🛠		prefer-exponentiation-operator	disallow the use of `Math.pow` in favor of the `**` operator
	🛠		prefer-object-spread	disallow using Object.assign with an object literal as the first argument and prefer the use of object spread instead.
	🛠		quote-props	require quotes around object literal property names
	🛠		quotes	enforce the consistent use of either backticks, double, or single quotes
	🛠		semi	require or disallow semicolons instead of ASI
	🛠		semi-spacing	enforce consistent spacing before and after semicolons
	🛠		semi-style	enforce location of semicolons
			sort-keys	require object keys to be sorted
	🛠		sort-vars	require variables within the same declaration block to be sorted
	🛠		space-before-blocks	enforce consistent spacing before blocks
	🛠		space-before-function-paren	enforce consistent spacing before `function` definition opening parenthesis
	🛠		space-in-parens	enforce consistent spacing inside parentheses
	🛠		space-infix-ops	require spacing around infix operators
	🛠		space-unary-ops	enforce consistent spacing before or after unary operators
	🛠		spaced-comment	enforce consistent spacing after the `//` or `/*` in a comment
	🛠		switch-colon-spacing	enforce spacing around colons of switch statements
	🛠		template-tag-spacing	require or disallow spacing between template tags and their literals
	🛠		unicode-bom	require or disallow Unicode byte order mark (BOM)
	🛠		wrap-regex	require parenthesis around regex literals

ES6

Rec	Fix	Status	Rule	Description
	🛠	🔴	arrow-body-style	require braces around arrow function bodies `as-needed` `requireReturnForObjectLiteral: false`
	🛠	🔴	arrow-parens	require parentheses around arrow function arguments `as-needed`
	🛠	🔴	arrow-spacing	enforce consistent spacing before and after the arrow in arrow functions `before: true` `after: true`
✔		🔴	constructor-super	require `super()` calls in constructors
	🛠	🔴	generator-star-spacing	enforce consistent spacing around `*` operators in generator functions `before: false` `after: true`
✔		🔴	no-class-assign	disallow reassigning class members
	🛠	🔴	no-confusing-arrow	disallow arrow functions where they could be confused with comparisons `allowParens: true`
✔		🔴	no-const-assign	disallow reassigning `const` variables
✔		🔴	no-dupe-class-members	disallow duplicate class members
		ⓧ	no-duplicate-imports	disallow duplicate module imports See: https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-duplicates.md
✔		🔴	no-new-symbol	disallow `new` operators with the `Symbol` object
		ⓧ	no-restricted-exports	disallow specified names in exports
		ⓧ	no-restricted-imports	disallow specified modules when loaded by `import`
✔		🔴	no-this-before-super	disallow `this`/`super` before calling `super()` in constructors
	🛠	🔴	no-useless-computed-key	disallow unnecessary computed property keys in objects and classes
		ⓧ	no-useless-constructor	disallow unnecessary constructors
	🛠	🔴	no-useless-rename	disallow renaming import, export, and destructured assignments to the same name `ignoreDestructuring: false` `ignoreImport: false` `ignoreExport: false`
	🛠	🔴	no-var	require `let` or `const` instead of `var`
	🛠	🔴	object-shorthand	require or disallow method and property shorthand syntax for object literals `always` `ignoreConstructors: false` `avoidQuotes: true`
	🛠	🔴	prefer-arrow-callback	require using arrow functions for callbacks `allowNamedFunctions: false` `allowUnboundThis: true`
	🛠	🔴	prefer-const	require `const` declarations for variables that are never reassigned after declared `destructuring: 'any'` `ignoreReadBeforeAssign: true`
	🛠	🔴	prefer-destructuring	require destructuring from arrays and/or objects `array: true` `object: true` `enforceForRenamedProperties: false`
	🛠	🔴	prefer-numeric-literals	disallow `parseInt()` and `Number.parseInt()` in favor of binary, octal, and hexadecimal literals
		🔴	prefer-rest-params	require rest parameters instead of `arguments`
		🔴	prefer-spread	require spread operators instead of `.apply()`
	🛠	🔴	prefer-template	require template literals instead of string concatenation
✔		🔴	require-yield	require generator functions to contain `yield`
	🛠	🔴	rest-spread-spacing	enforce spacing between rest and spread operators and their expressions `never`
	🛠	ⓧ	sort-imports	enforce sorted import declarations within modules See: #12
		🔴	symbol-description	require symbol descriptions
	🛠	🔴	template-curly-spacing	require or disallow spacing around embedded expressions of template strings
	🛠	🔴	yield-star-spacing	require or disallow spacing around the `` in `yield` expressions `after`