@typescript-eslint/parser

Features

• eslint-plugin: [no-base-to-string] add support for catching toLocaleString

• eslint-plugin: [no-unnecessary-type-parameters] add suggestion fixer

Fixes

• eslint-plugin: [class-literal-property-style] don't report nodes with override keyword

• rule-tester: allow custom filename outside directory

Features

• rule-tester: hooks for test cases

Fixes

• eslint-plugin: [no-unnecessary-type-parameters] cannot assume variables are either type or value

• eslint-plugin: [return-await] sync the behavior with await-thenable

• eslint-plugin: [prefer-literal-enum-member] report a different error message when allowBitwiseExpressions is enabled

• eslint-plugin: [no-loop-func] sync from upstream base rule

• eslint-plugin: [no-unused-vars] never report the naming of an enum member

• eslint-plugin: correct use-at-your-own-risk type definitions

• eslint-plugin: handle unions in await...for

• rule-tester: merge provided linterOptions

• scope-manager: [no-use-before-define] do not treat nested namespace aliases as variable references

• typescript-estree: improve project service error message when file extension missing from extraFileExtensions

• visitor-keys: reorder TSSatisfiesExpression and TSTypeAssertion

Features

• eslint-plugin: [no-unnecessary-condition] add checkTypePredicates

• eslint-plugin: [await-thenable] check for-await loop iteree

Fixes

• removed

  Remove export type * in d.ts to support TS<5.0

• eslint-plugin: [no-unnecessary-template-expression] should underline template syntax with squiggly lines

• eslint-plugin: [no-deprecated] max callstack exceeded when class implements itself

• eslint-plugin: [no-misused-promises] check contextual type

• eslint-plugin: [prefer-literal-enum-member] allow nested bitwise operations

• type-utils: check for type parameters on isBuiltinSymbolLikeRecurser()

• utils: update missing type information message

Features

• eslint-plugin: [no-unsafe-call] check calls of Function

• eslint-plugin: [consistent-type-exports] check export * exports to see if all exported members are types

Fixes

• eslint-plugin: properly coerce all types to string in getStaticMemberAccessValue

• eslint-plugin: [no-deprecated] report on imported deprecated variables

• eslint-plugin: [no-confusing-non-null-assertion] check !in and !instanceof

• types: add NewExpression as a parent of SpreadElement

• utils: add missing entries to the RuleListener selectors list

Features

• Add allow option for restrict-template-expressions

• eslint-plugin: [no-unnecessary-condition] check switch cases

• eslint-plugin: [no-misused-promises] check array predicate return

• type-utils: isNullableType add Void logic

• typescript-estree: disable plugin loading by default in project service

Fixes

• eslint-plugin: [no-deprecated] don't report recursive types in destructuring assignment twice

• eslint-plugin: [no-deprecated] report on deprecated variables used in destructuring assignment

• eslint-plugin: [no-deprecated] report on deprecated properties with function-like types

• eslint-plugin: [no-unnecessary-condition] properly reflect multiple negations in message

• typescript-estree: don't throw on missing tsconfig.json by default in project service

Features

• eslint-plugin: [no-duplicate-type-constituents] prevent unnecessary | undefined for optional parameters

• eslint-plugin: [no-unsafe-argument] differentiate error types

• typescript-estree: default projectService.defaultProject to 'tsconfig.json'

Fixes

• eslint-plugin: [no-unnecessary-type-assertion] fix TSNonNullExpression fixer

• eslint-plugin: [no-misused-promises] handle static method

• eslint-plugin: [no-unnecessary-type-parameters] fix AST quick path scope analysis

• eslint-plugin: [consistent-type-assertions] access parser services lazily

Features

• eslint-plugin: [no-deprecated] add rule

• typescript-estree: replace globby w/ fast-glob

• typescript-estree: reload project service once when file config isn't found

Fixes

• ast-spec: use Expression in argument of ThrowStatement

• eslint-plugin: [no-unnecessary-template-expression] add missing parentheses in autofix

• eslint-plugin: [no-unnecessary-type-parameters] check mapped alias type arguments

• utils: add missing TSSatisfiesExpression in RuleListenerBaseSelectors

• utils: add TSDeclareFunction to functionTypeTypes

Features

• eslint-plugin: add suggestion to require-await to remove async keyword

• typescript-estree: special-case error for parserOptions.project and project references

Fixes

• eslint-plugin: [use-unknown-in-catch-callback-variable] flag second argument of .then

• eslint-plugin: [no-unnecessary-type-assertion] conflict with TS for variables used before assignment

• eslint-plugin: delete in message if ReadOnly<string> is detected

• eslint-plugin: [no-redundant-type-constituents] differentiate a types-error any from a true any

• eslint-plugin: [no-unnecessary-type-parameters] check mapped constraint types if necessary

• eslint-plugin: [no-unsafe-enum-comparison] add logic to see through intersections

• typescript-estree: pass in tsconfigRootDir as cwd to getParsedConfigFile

Features

• eslint-plugin: [no-floating-promises] enable "add await" suggestion if ignoreVoid is true

• eslint-plugin: [no-unsafe-return] check promise any

• eslint-plugin: [no-misused-promises] check subtype methods against heritage type methods

• typescript-eslint: add JSDoc comments on generated configs

• typescript-estree: restrict variable declarator definite/init combinations

Fixes

• eslint-plugin: [no-unnecessary-type-parameters] skip checking function bodies for AST references

• eslint-plugin: [member-ordering] get accessor member name & take into account abstract and decorator

• eslint-plugin: [prefer-optional-chain] wrong parenthesis fix output

• eslint-plugin: [no-unnecessary-type-parameters] clarify message

• utils: correct types to align with @types/eslint v9

For more information, please see our blog post on this release: typescript-eslint.io/blog/announcing-typescript…

Raw Changelog

Breaking Changes

• breaking

  typescript-estree: split TSMappedType typeParameter into constraint and key

• breaking

  parser: always enable comment, loc, range, tokens

• breaking

  eslint-plugin: [prefer-nullish-coalescing] change ignoreConditionalTests default to true

• breaking

  typescript-estree: enable dot globs for project by default

• deprecated

  eslint-plugin: deprecate no-loss-of-precision extension rule

• breaking

  eslint-plugin: remove formatting/layout rules

• breaking

  typescript-estree: remove slow deprecated and isolated programs

• breaking

  typescript-estree: add TSEnumBody node for TSEnumDeclaration body

• breaking

  typescript-estree: rename automaticSingleRunInference to disallowAutomaticSingleRunInference

• breaking

  ast-spec: remove deprecated type params

• breaking

  type-utils: remove IsNullableTypeOptions interface

• breaking

  eslint-plugin: [no-unused-vars] align catch behavior to ESLint 9

• breaking

  utils: swap LegacyESLint out for FlatESLint as ESLint export

• breaking

  eslint-plugin: split no-empty-object-type out from ban-types and no-empty-interfaces

• breaking

  utils: allow specifying additional rule meta.docs in RuleCreator

• breaking

  eslint-plugin: apply initial config changes for v8

• breaking

  eslint-plugin: replace ban-types with no-restricted-types, no-unsafe-function-type, no-wrapper-object-types

• breaking

  typescript-estree: remove EXPERIMENTAL_useSourceOfProjectReferenceRedirect

• breaking

  eslint-plugin: remove no-useless-template-literals

• breaking

  type-utils: remove getTokenAtPosition

• breaking

  eslint-plugin: [no-floating-promises] disable checkThenables by default for v8

• breaking

  rule-tester: switched to flat config

Features

• Stricter parent types for the AST

• Speed up non-type-aware linting with project service

• v8 integration branch

• removed

  eslint-plugin: remove deprecated no-throw-literal rule

• eslint-plugin: [no-floating-promises] add 'allowForKnownSafeCalls' option

• eslint-plugin: [no-unused-vars] add reportUnusedIgnorePattern option

• eslint-plugin: [no-unused-vars] support ignoreClassWithStaticInitBlock

• eslint-plugin: [no-unused-vars] handle comma operator for assignments, treat for-of the same as for-in

• eslint-plugin: [no-unused-vars] report if var used only in typeof

• eslint-plugin: [return-await] add return-await to strict-type-checked preset

• eslint-plugin: [no-unnecessary-type-parameters] promote to strict

• rule-tester: support multipass fixes

• type-utils: support intersection types in TypeOrValueSpecifier

• typescript-estree: stabilize EXPERIMENTAL_useProjectService as projectService

• typescript-estree: also remove projectService in withoutProjectParserOptions

• typescript-estree: exposes ProjectService logs through the plugin

• utils: add Linter configType constructor option

• removed

  utils: remove deprecated context helpers

Fixes

• Correct eslint-plugin's peerDependency on parser@8

• Bring back in allowdefaultprojectforfiles rename

• Disable projectService in disabled-type-checked shared config

• eslint-plugin: include alpha pre-releases in parser peer dependency

• eslint-plugin: correct rules.d.ts types to not rely on non-existent imports

• eslint-plugin: remove duplicate import RuleModuleWithMetaDocs

• eslint-plugin: [no-unnecessary-template-expression] do not render escaped strings in autofixes

• eslint-plugin: [no-unused-vars] incorporate upstream changes around caught errors report messages

• eslint-plugin: [no-misused-promises] perf: avoid getting types of variables/functions if the annotated type is obviously not a function

• rule-tester: set configType to eslintrc in Linter options

• rule-tester: re-apply updates from main

• rule-tester: provide Linter a cwd in its constructor

• type-utils: also check declared modules for package names in TypeOrValueSpecifier

• types: allow ProjectServiceOptions for projectService

• typescript-estree: pass extraFileExtensions to projectService

• typescript-estree: only run projectService setHostConfiguration when needed

• typescript-estree: specific error for parserOptions.project not including a file

• typescript-estree: adds support for project services using extended config files

• typescript-estree: factor tsconfigRootDir into allowDefaultProject

Features

• types: update ECMA versions

Fixes

• eslint-plugin: [no-unnecessary-type-assertion] prevent runtime error when asserting a variable declared in default TS lib

• eslint-plugin: [unbound-method] report on destructuring in function parameters

• eslint-plugin: [no-duplicate-type-constituents] shouldn't report on error types

• eslint-plugin: [strict-boolean-expressions] support branded booleans

Features

• eslint-plugin: backport no-unsafe-function type, no-wrapper-object-types from v8 to v7

• deprecated

  eslint-plugin: [return-await] add option to report in error-handling scenarios only, and deprecate "never"

Fixes

• eslint-plugin: [no-floating-promises] check top-level type assertions (and more)

• eslint-plugin: [strict-boolean-expressions] consider assertion function argument a boolean context

• eslint-plugin: [no-unnecessary-condition] false positive on optional private field

• typescript-estree: don't infer single-run when --fix is in proces.argv

• typescript-estree: disable single-run inference with extraFileExtensions

Features

• ast-spec: add parent property to AccessorProperty node types

• eslint-plugin: [no-unnecessary-type-parameters] port from v8 to v7

• eslint-plugin: [no-unnecessary-parameter-property-assignment] add new rule

• eslint-plugin: add support for nested namespaces to unsafe-member-access

• eslint-plugin: [no-floating-promises] add checkThenables option

• rule-tester: stricter rule test validations

Fixes

• eslint-plugin: [no-floating-promises] add suggestions to tests from #9263 checkThenables (#9515, #9263)

• eslint-plugin: [restrict-template-expressions] don't report tuples if allowArray option is enabled

• utils: context.parserPath may be undefined

Features

• eslint-plugin: [array-type] detect Readonly<string> case

• eslint-plugin: back-port new rules around empty object types from v8

Fixes

• Disable EXPERIMENTAL_useProjectService in disabled-type-checked shared config

• eslint-plugin: [no-unsafe-return] differentiate a types-error any from a true any

• eslint-plugin: [no-unsafe-call] differentiate a types-error any from a true any

• utils: clean outdated RuleTester export

Features

• Support TypeScript 5.5

• ast-spec: tighter types and documentation for declaration/*

Fixes

• Keep warnAbountTSVersion in sync with package.json

• eslint-plugin: [no-extraneous-class] handle abstract members

• eslint-plugin: [prefer-nullish-coalescing] handle intersected primitive types

• eslint-plugin: [no-invalid-this] support AccessorProperty

• eslint-plugin: [prefer-nullish-coalescing] treat enums and literals as their underlying primitive types

• eslint-plugin: [prefer-nullish-coalescing] ensure ternary fix does not remove parens

We followed this up soon after with 7.14.1 - see the combined release notes here github.com/typescript-eslint/typescript-eslint/…

You can read about our versioning strategy and releases on our website.

Features

• eslint-plugin: [no-dynamic-delete] allow all string literals as index

• parser, typescript-estree: export withoutProjectParserOptions utility

• typescript-estree: require import = require() argument to be a string literal

• typescript-estree: forbid .body, .async, .generator on declare function

Fixes

• ast-spec: function-call-like callee should be Expression not LeftHandSideExpression

• eslint-plugin: [init-declarations] refine report locations

• eslint-plugin: [no-base-to-string] make error message more nuanced

• eslint-plugin: [no-unsafe-assignment] be more specific about error types

• eslint-plugin: [no-magic-numbers] fix implementation of the ignore option

• scope-manager: handle index signature in class

Features

• eslint-plugin: [no-useless-template-literals] rename to no-unnecessary-template-expression (deprecate no-useless-template-literals)

• eslint-plugin: [no-floating-promises] add option 'allowForKnownSafePromises'

• rule-tester: check for parsing errors in suggestion fixes

• rule-tester: port checkDuplicateTestCases from ESLint

Fixes

• eslint-plugin: [no-unnecessary-type-assertion] combine template literal check with const variable check

• eslint-plugin: [dot-notation] fix false positive when accessing private/protected property with optional chaining

• eslint-plugin: [explicit-member-accessibility] refine report locations

• eslint-plugin: [no-unnecessary-type-assertion] declares are always defined, so always check declares

• eslint-plugin: [prefer-literal-enum-member] allow using member it self on allowBitwiseExpressions

• eslint-plugin: [return-await] clean up in-try-catch detection and make autofixes safe

• eslint-plugin: [member-ordering] also TSMethodSignature can be get/set

• types: correct typing ParserOptions

Features

• deprecated

  eslint-plugin: deprecate prefer-ts-expect-error in favor of ban-ts-comment

Fixes

• ast-spec: add EmptyStatement to Statement

• eslint-plugin: [consistent-type-assertions] prevent syntax errors on arrow functions

• typescript-estree: truncate number of files printed by the maximum file error

Features

• eslint-plugin: [sort-type-constituents] support case sensitive sorting

Fixes

• eslint-plugin: [prefer-regexp-exec] fix heuristic to check whether regex may contain global flag

• typescript-estree: don't add in-project files to defaultProjectMatchedFiles

• utils: remove function form type from flat config files and ignores

Features

• rule-tester: assert suggestion messages are unique

• typescript-estree: add maximumDefaultProjectFileMatchCount and wide allowDefaultProjectForFiles glob restrictions

Fixes

• eslint-plugin: [no-unsafe-argument] handle tagged templates

• eslint-plugin: [prefer-optional-chain] suggests optional chaining during strict null equality check

• eslint-plugin: [consistent-type-assertions] handle tagged templates

• eslint-plugin: [no-unsafe-return] handle union types

• eslint-plugin: [no-unused-vars] clear error report range

• utils: export ESLint backwards-compat functions

Features

• Add name field to shared configs and flat config types

• Bump npm dependency ranges

  • note: this does not include support for ESLint v9 - see #8211 for progress.

• utils: add types for both flat and legacy eslint classes

Fixes

• typescript-eslint: fix type errors when using exactOptionalPropertyTypes

Fixes

• eslint-plugin: [no-floating-promises] handle TaggedTemplateExpression

• eslint-plugin: [no-unnecessary-type-assertion] handle exactOptionalPropertyTypes compiler option

• parser: disallow errorOnTypeScriptSyntacticAndSemanticIssues

• typescript-eslint: improve support for legacy configs

Features

• eslint-plugin: [consistent-type-imports] ignore files with decorators, experimentalDecorators, and emitDecoratorMetadata

  • Check out our blog post on this change for more information! typescript-eslint.io/blog/changes-to-consistent…

• eslint-plugin: [no-unnecessary-type-arguments] handle tagged templates

• deprecated

  eslint-plugin: deprecate no-throw-literal and add a renamed only-throw-error

Fixes

• eslint-plugin: [prefer-optional-chain] address multipart nullish checks false positive

• eslint-plugin: [prefer-optional-chain] properly disambiguate between boolean and false

• eslint-plugin: [no-unnecessary-type-assertion] avoid remove const casting on template literals with expressions inside

• typescript-eslint: declare peer dependency on utils to ensure npm correctly installs dependencies

Note that this release enables rules to have more restrictive default options as configured in the strict and strict-type-checked configs. See #8364 for more details.

Features

• eslint-plugin: [restrict-template-expressions] add allowArray option

• eslint-plugin: add meta.docs.recommended setting for strict config options

• eslint-plugin: add rule use-unknown-in-catch-callback-variables

• eslint-plugin: [prefer-reduce-type-parameter] supports tuple, union, intersection

• eslint-plugin-internal: add internal lint rule no-relative-paths-to-internal-packages

• typescript-estree: disallow switch statements with multiple default cases

• utils: add parser name to thrown parser error message

Fixes

• Correct engines.node constraints in package.json

• eslint-plugin: [unbound-method] check method definition in object literal using longhand form

• eslint-plugin: [consistent-type-imports] handle imports without specifiers

• eslint-plugin: [no-redundant-type-constituents] incorrectly marks & string as redundant

• eslint-plugin: [no-unnecessary-qualifier] handle merge namespace with enum

• eslint-plugin: [no-unused-expressions] false negatives when using assertions

• eslint-plugin: [ban-ts-comment] more accurate handling of multiline comments

• eslint-plugin: [explicit-function-return-type, explicit-module-boundary-types] improved checking for allowHigherOrderFunctions option

• eslint-plugin: [class-literal-property-style] ignore property assigned in constructor

• eslint-plugin: [no-unnecessary-type-assertion] fix false negative for const variable declarations

• typescript-estree: fix the issue of single run inferring in the pnpm repo (#3811, #8702)

Features

• Support TS 5.4

• eslint-plugin: [prefer-string-starts-ends-with] add allowSingleElementEquality option

Fixes

• eslint-plugin: expose *-type-checked-only configs for extension

• eslint-plugin: [member-ordering] report alphabetical sorting for all groups instead of just the first failing group

• eslint-plugin: [no-var-requires, no-require-imports] support template literal

• eslint-plugin: [no-useless-template-literals] detect TemplateLiteral

• eslint-plugin: [no-unnecessary-condition] handle union array and tuple type

• eslint-plugin: [prefer-find] support ternary branches in prefer-find

• typescript-eslint: set sourceType: "module" in base shared config

• typescript-eslint: export ConfigWithExtends type

Features

• eslint-plugin: add *-type-checked-only configs

• eslint-plugin: [naming-convention] support the auto-accessor syntax

• eslint-plugin: [consistent-return] add new rule

• typescript-estree: add debug logs for useProgramFromProjectService

Fixes

• eslint-plugin: [prefer-optional-chan] allow typeof for avoiding reference error

• eslint-plugin: [no-misused-promises] improve check union types

• eslint-plugin: [no-use-before-define] fix false positive type reference in as, satisfies

• typescript-estree: use simpler absolutify behavior for project service client file paths

Read more about this release: typescript-eslint.io/blog/announcing-typescript…

Auto-Generated Release Notes

Features

• Add support for flat configs

Fixes

• eslint-plugin: [prefer-find] stop throwing type errors when converting symbols to numbers

Breaking Changes

• breaking

  ⚠️ bump ESLint, NodeJS, and TS minimum version requirements

Features

• Export plugin metadata

• Allow parserOptions.project: false

• eslint-plugin: add rule prefer-find

• typescript-estree: forbid duplicated accessibility modifiers

• utils: improve eslint types

Fixes

• ast-spec: add JSXElement type to the JSXAttribute['value']

• eslint-plugin: [no-unused-vars] don't report on types referenced in export assignment expression

• eslint-plugin: [switch-exhaustiveness-check] better support for intersections, infinite types, non-union values

• eslint-plugin: [consistent-type-imports] dont report on types used in export assignment expressions

• eslint-plugin: [no-unnecessary-condition] handle left-hand optional with exactOptionalPropertyTypes option

• eslint-plugin: [class-literal-property-style] allow getter when same key setter exists

• eslint-plugin: [no-unnecessary-type-assertion] provide valid fixes for assertions with extra tokens before as keyword

• rule-tester: fix a phantom dependency on the "semver" package

Features

• eslint-plugin: [member-ordering] allow easy reuse of the default ordering

Fixes

• eslint-plugin: [no-useless-template-literals] incorrect bigint autofix result

• eslint-plugin: [prefer-nullish-coalescing] treat any/unknown as non-nullable

• eslint-plugin: [no-useless-template-literals] report Infinity & NaN

• eslint-plugin: [prefer-readonly] disable checking accessors

Features

• eslint-plugin: [prefer-promise-reject-errors] add rule

• eslint-plugin: [no-array-delete] add new rule

• eslint-plugin: [no-useless-template-literals] add fix suggestions

Fixes

• eslint-plugin: [no-unnecessary-type-assertion] detect unnecessary non-null-assertion on a call expression

• eslint-plugin: [no-unnecesary-type-assertion] treat unknown/any as nullable

• typescript-estree: add JSDocParsingMode enum merge for typescript/lib/tsserverlibrary

• typescript-estree: disallow using as the variable keyword for for..in loops

• typescript-estree: fix incorrect backwards-compat augmentation in TS 5.3

Bug Fixes

• eslint-plugin: [no-restricted-imports] prevent crash when patterns or paths in options are empty

Features

• eslint-plugin: [no-floating-promises] flag result of .map(async)

• eslint-plugin: [switch-exhaustiveness-check] add an option to warn against a default case on an already exhaustive switch

You can read about our versioning strategy and releases on our website.

Bug Fixes

• eslint-plugin: [unbound-method] exempt all non-Promise built-in statics

Features

• deprecated

  eslint-plugin: deprecate formatting rules

• typescript-estree: add allowDefaultProjectForFiles project service allowlist option

You can read about our versioning strategy and releases on our website.

Features

• eslint-plugin: [no-useless-template-literals] add new rule (#7957) (ff75785), closes #2846

• eslint-plugin: [require-array-sort-compare] support toSorted

You can read about our versioning strategy and releases on our website.