typescript-eslint · JoshuaKGoldberg · Oct 21, 2024 · Aug 20, 2024 · Aug 20, 2024 · Oct 11, 2024
diff --git a/eslint.config.mjs b/eslint.config.mjs
@@ -613,6 +613,7 @@ export default tseslint.config(
       'packages/scope-manager/{src,tests}/**/*.ts',
       'packages/types/{src,tools}/**/*.ts',
       'packages/typescript-eslint/{src,tests}/**/*.ts',
+      'packages/typescript-estree/{src,tests,typings}/**/*.ts',
       'packages/utils/src/**/*.ts',
       'packages/visitor-keys/src/**/*.ts',
       'packages/website*/src/**/*.ts',
@@ -625,7 +626,7 @@ export default tseslint.config(
       'perfectionist/sort-union-types': [
         'error',
         {
-          groups: ['unknown', 'keyword', 'nullish'],
+          groups: ['keyword', 'unknown', 'nullish'],
           type: 'natural',
         },
       ],
@@ -682,4 +683,19 @@ export default tseslint.config(
       ],
     },
   },
+  {
+    files: ['packages/typescript-estree/src/**/*.ts'],
+    rules: {
+      'perfectionist/sort-objects': [
+        'error',
+        {
+          customGroups: {
+            first: ['type'],
+            second: ['loc', 'range'],
+          },
+          groups: ['first', 'second'],
+        },
+      ],
+    },
+  },
 );
diff --git a/packages/ast-spec/src/base/LiteralBase.ts b/packages/ast-spec/src/base/LiteralBase.ts
@@ -4,5 +4,5 @@ import type { BaseNode } from './BaseNode';
 export interface LiteralBase extends BaseNode {
   type: AST_NODE_TYPES.Literal;
   raw: string;
-  value: RegExp | bigint | boolean | number | string | null;
+  value: bigint | boolean | number | string | RegExp | null;
 }
diff --git a/packages/ast-spec/src/type/TSMappedType/spec.ts b/packages/ast-spec/src/type/TSMappedType/spec.ts
@@ -9,8 +9,8 @@ export interface TSMappedType extends BaseNode {
   constraint: TypeNode;
   key: Identifier;
   nameType: TypeNode | null;
-  optional: '+' | '-' | boolean | undefined;
-  readonly: '+' | '-' | boolean | undefined;
+  optional: boolean | '+' | '-' | undefined;
+  readonly: boolean | '+' | '-' | undefined;
   typeAnnotation: TypeNode | undefined;
   /** @deprecated Use {@link `constraint`} and {@link `key`} instead. */
   typeParameter: TSTypeParameter;

diff --git a/packages/eslint-plugin/src/rules/ban-ts-comment.ts b/packages/eslint-plugin/src/rules/ban-ts-comment.ts
@@ -5,9 +5,9 @@ import { AST_TOKEN_TYPES } from '@typescript-eslint/utils';
 import { createRule, getStringLength, nullThrows } from '../util';
 
 type DirectiveConfig =
+  | boolean
   | 'allow-with-description'
-  | { descriptionFormat: string }
-  | boolean;
+  | { descriptionFormat: string };
 
 interface Options {
   minimumDescriptionLength?: number;

diff --git a/packages/eslint-plugin/src/rules/class-methods-use-this.ts b/packages/eslint-plugin/src/rules/class-methods-use-this.ts
@@ -13,7 +13,7 @@ type Options = [
   {
     enforceForClassFields?: boolean;
     exceptMethods?: string[];
-    ignoreClassesThatImplementAnInterface?: 'public-fields' | boolean;
+    ignoreClassesThatImplementAnInterface?: boolean | 'public-fields';
     ignoreOverrideMethods?: boolean;
   },
 ];

diff --git a/packages/eslint-plugin/src/rules/member-ordering.ts b/packages/eslint-plugin/src/rules/member-ordering.ts
@@ -995,7 +995,7 @@ export default createRule<Options, MessageIds>({
 
       // Standardize config
       let order: Order | undefined;
-      let memberTypes: MemberType[] | string | undefined;
+      let memberTypes: string | MemberType[] | undefined;
       let optionalityOrder: OptionalityOrder | undefined;
 
       /**

diff --git a/packages/eslint-plugin/src/rules/naming-convention-utils/types.ts b/packages/eslint-plugin/src/rules/naming-convention-utils/types.ts
@@ -23,7 +23,7 @@ interface MatchRegex {
 
 interface Selector {
   custom?: MatchRegex;
-  filter?: MatchRegex | string;
+  filter?: string | MatchRegex;
   // format options
   format: PredefinedFormatsString[] | null;
   leadingUnderscore?: UnderscoreOptionsString;

diff --git a/packages/eslint-plugin/src/rules/no-invalid-void-type.ts b/packages/eslint-plugin/src/rules/no-invalid-void-type.ts
@@ -6,7 +6,7 @@ import { createRule } from '../util';
 
 interface Options {
   allowAsThisParameter?: boolean;
-  allowInGenericTypeArguments?: [string, ...string[]] | boolean;
+  allowInGenericTypeArguments?: boolean | [string, ...string[]];
 }
 
 type MessageIds =

diff --git a/packages/eslint-plugin/src/rules/no-misused-promises.ts b/packages/eslint-plugin/src/rules/no-misused-promises.ts
@@ -18,7 +18,7 @@ type Options = [
   {
     checksConditionals?: boolean;
     checksSpreads?: boolean;
-    checksVoidReturn?: ChecksVoidReturnOptions | boolean;
+    checksVoidReturn?: boolean | ChecksVoidReturnOptions;
   },
 ];
 
@@ -43,7 +43,7 @@ type MessageId =
   | 'voidReturnVariable';
 
 function parseChecksVoidReturn(
-  checksVoidReturn: ChecksVoidReturnOptions | boolean | undefined,
+  checksVoidReturn: boolean | ChecksVoidReturnOptions | undefined,
 ): ChecksVoidReturnOptions | false {
   switch (checksVoidReturn) {
     case false:

diff --git a/packages/eslint-plugin/src/rules/no-restricted-types.ts b/packages/eslint-plugin/src/rules/no-restricted-types.ts
@@ -6,13 +6,13 @@ import { createRule, objectReduceKey } from '../util';
 
 type Types = Record<
   string,
+  | boolean
+  | string
   | {
       fixWith?: string;
       message: string;
       suggest?: readonly string[];
     }
-  | boolean
-  | string
   | null
 >;
 
@@ -37,7 +37,7 @@ function stringifyNode(
 }
 
 function getCustomMessage(
-  bannedType: { fixWith?: string; message?: string } | true | string | null,
+  bannedType: string | { fixWith?: string; message?: string } | true | null,
 ): string {
   if (!bannedType || bannedType === true) {
     return '';

diff --git a/packages/eslint-plugin/src/rules/no-use-before-define.ts b/packages/eslint-plugin/src/rules/no-use-before-define.ts
@@ -12,7 +12,7 @@ const SENTINEL_TYPE =
 /**
  * Parses a given value as options.
  */
-function parseOptions(options: Config | string | null): Required<Config> {
+function parseOptions(options: string | Config | null): Required<Config> {
   let functions = true;
   let classes = true;
   let enums = true;

diff --git a/packages/eslint-plugin/src/util/collectUnusedVariables.ts b/packages/eslint-plugin/src/util/collectUnusedVariables.ts
@@ -234,7 +234,7 @@ class UnusedVarsVisitor extends Visitor {
   private markVariableAsUsed(name: string, parent: TSESTree.Node): void;
 
   private markVariableAsUsed(
-    variableOrIdentifierOrName: ScopeVariable | TSESTree.Identifier | string,
+    variableOrIdentifierOrName: string | ScopeVariable | TSESTree.Identifier,
     parent?: TSESTree.Node,
   ): void {
     if (

diff --git a/packages/eslint-plugin/tests/configs.test.ts b/packages/eslint-plugin/tests/configs.test.ts
@@ -17,8 +17,8 @@ const EXTENSION_RULES = Object.entries(rules)
   );
 
 function filterRules(
-  values: Record<string, unknown[] | string>,
-): [string, unknown[] | string][] {
+  values: Record<string, string | unknown[]>,
+): [string, string | unknown[]][] {
   return Object.entries(values).filter(([name]) =>
     name.startsWith(RULE_NAME_PREFIX),
   );
@@ -84,7 +84,7 @@ function filterAndMapRuleConfigs({
 }
 
 function itHasBaseRulesOverriden(
-  unfilteredConfigRules: Record<string, unknown[] | string>,
+  unfilteredConfigRules: Record<string, string | unknown[]>,
 ): void {
   it('has the base rules overriden by the appropriate extension rules', () => {
     const ruleNames = new Set(Object.keys(unfilteredConfigRules));
@@ -196,7 +196,7 @@ describe('recommended-type-checked-only.ts', () => {
 });
 
 describe('strict.ts', () => {
-  const unfilteredConfigRules: Record<string, unknown[] | string> =
+  const unfilteredConfigRules: Record<string, string | unknown[]> =
     plugin.configs.strict.rules;
 
   it('contains all strict rules, excluding type checked ones', () => {
@@ -217,7 +217,7 @@ describe('strict.ts', () => {
 });
 
 describe('strict-type-checked.ts', () => {
-  const unfilteredConfigRules: Record<string, unknown[] | string> =
+  const unfilteredConfigRules: Record<string, string | unknown[]> =
     plugin.configs['strict-type-checked'].rules;
 
   it('contains all strict rules', () => {
@@ -236,7 +236,7 @@ describe('strict-type-checked.ts', () => {
 });
 
 describe('strict-type-checked-only.ts', () => {
-  const unfilteredConfigRules: Record<string, unknown[] | string> =
+  const unfilteredConfigRules: Record<string, string | unknown[]> =
     plugin.configs['strict-type-checked-only'].rules;
 
   it('contains only type-checked strict rules', () => {
@@ -257,7 +257,7 @@ describe('strict-type-checked-only.ts', () => {
 });
 
 describe('stylistic.ts', () => {
-  const unfilteredConfigRules: Record<string, unknown[] | string> =
+  const unfilteredConfigRules: Record<string, string | unknown[]> =
     plugin.configs.stylistic.rules;
 
   it('contains all stylistic rules, excluding deprecated or type checked ones', () => {

diff --git a/packages/eslint-plugin/tests/docs.test.ts b/packages/eslint-plugin/tests/docs.test.ts
@@ -435,7 +435,7 @@ describe('Validating rule docs', () => {
 
         function lintCodeBlock(
           token: mdast.Code,
-          shouldContainLintErrors: 'skip-check' | boolean,
+          shouldContainLintErrors: boolean | 'skip-check',
         ): void {
           const lang = token.lang?.trim();
           if (!lang || !/^tsx?\b/i.test(lang)) {

diff --git a/packages/eslint-plugin/tests/rules/prefer-nullish-coalescing.test.ts b/packages/eslint-plugin/tests/rules/prefer-nullish-coalescing.test.ts
@@ -30,15 +30,15 @@ const nullishTypes = ['null', 'undefined', 'null | undefined'];
 const ignorablePrimitiveTypes = ['string', 'number', 'boolean', 'bigint'];
 
 function typeValidTest(
-  cb: (type: string) => ValidTestCase<Options> | string,
-): (ValidTestCase<Options> | string)[] {
+  cb: (type: string) => string | ValidTestCase<Options>,
+): (string | ValidTestCase<Options>)[] {
   return types.map(type => cb(type));
 }
 function nullishTypeTest<
   T extends
+    | string
     | InvalidTestCase<MessageIds, Options>
-    | ValidTestCase<Options>
-    | string,
+    | ValidTestCase<Options>,
 >(cb: (nullish: string, type: string) => T): T[] {
   return nullishTypes.flatMap(nullish => types.map(type => cb(nullish, type)));
 }

diff --git a/packages/eslint-plugin/typings/eslint-rules.d.ts b/packages/eslint-plugin/typings/eslint-rules.d.ts
@@ -256,11 +256,11 @@ declare module 'eslint/lib/rules/no-restricted-globals' {
   const rule: TSESLint.RuleModule<
     'customMessage' | 'defaultMessage',
     (
+      | string
       | {
           message?: string;
           name: string;
         }
-      | string
     )[],
     unknown,
     {
@@ -539,14 +539,14 @@ declare module 'eslint/lib/rules/no-restricted-imports' {
 
   namespace rule {
     export type ArrayOfStringOrObject = (
+      | string
       | {
           // extended
           allowTypeImports?: boolean;
           importNames?: string[];
           message?: string;
           name: string;
         }
-      | string
     )[];
     export type ArrayOfStringOrObjectPatterns =
       | {

diff --git a/packages/parser/src/parser.ts b/packages/parser/src/parser.ts
@@ -79,14 +79,14 @@ function getLib(compilerOptions: ts.CompilerOptions): Lib[] {
 }
 
 function parse(
-  code: ts.SourceFile | string,
+  code: string | ts.SourceFile,
   options?: ParserOptions,
 ): ParseForESLintResult['ast'] {
   return parseForESLint(code, options).ast;
 }
 
 function parseForESLint(
-  code: ts.SourceFile | string,
+  code: string | ts.SourceFile,
   parserOptions?: ParserOptions | null,
 ): ParseForESLintResult {
   if (!parserOptions || typeof parserOptions !== 'object') {

diff --git a/packages/rule-tester/src/RuleTester.ts b/packages/rule-tester/src/RuleTester.ts
@@ -258,7 +258,7 @@ export class RuleTester extends TestFramework {
    * Adds the `only` property to a test to run it in isolation.
    */
   static only<Options extends readonly unknown[]>(
-    item: ValidTestCase<Options> | string,
+    item: string | ValidTestCase<Options>,
   ): ValidTestCase<Options>;
   /**
    * Adds the `only` property to a test to run it in isolation.
@@ -268,9 +268,9 @@ export class RuleTester extends TestFramework {
   ): InvalidTestCase<MessageIds, Options>;
   static only<MessageIds extends string, Options extends readonly unknown[]>(
     item:
+      | string
       | InvalidTestCase<MessageIds, Options>
-      | ValidTestCase<Options>
-      | string,
+      | ValidTestCase<Options>,
   ): InvalidTestCase<MessageIds, Options> | ValidTestCase<Options> {
     if (typeof item === 'string') {
       return { code: item, only: true };
@@ -833,7 +833,7 @@ export class RuleTester extends TestFramework {
   >(
     ruleName: string,
     rule: RuleModule<MessageIds, Options>,
-    itemIn: ValidTestCase<Options> | string,
+    itemIn: string | ValidTestCase<Options>,
     seenValidTestCases: Set<string>,
   ): void {
     const item: ValidTestCase<Options> =
@@ -1374,7 +1374,7 @@ function checkDuplicateTestCase(
  * value is a regular expression, it is checked against the actual
  * value.
  */
-function assertMessageMatches(actual: string, expected: RegExp | string): void {
+function assertMessageMatches(actual: string, expected: string | RegExp): void {
   if (expected instanceof RegExp) {
     // assert.js doesn't have a built-in RegExp match function
     assert.ok(

diff --git a/packages/rule-tester/src/types/DependencyConstraint.ts b/packages/rule-tester/src/types/DependencyConstraint.ts
@@ -6,7 +6,7 @@ export interface RangeOptions {
 }
 
 export interface SemverVersionConstraint {
-  readonly options?: RangeOptions | boolean;
+  readonly options?: boolean | RangeOptions;
   readonly range: string;
 }
 export type AtLeastVersionConstraint =

diff --git a/packages/rule-tester/src/types/InvalidTestCase.ts b/packages/rule-tester/src/types/InvalidTestCase.ts
@@ -76,5 +76,5 @@ export interface InvalidTestCase<
   /**
    * The expected code after autofixes are applied. If set to `null`, the test runner will assert that no autofix is suggested.
    */
-  readonly output?: string[] | string | null;
+  readonly output?: string | string[] | null;
 }
diff --git a/packages/rule-tester/src/types/index.ts b/packages/rule-tester/src/types/index.ts
@@ -18,7 +18,7 @@ export interface RunTests<
 > {
   readonly invalid: readonly InvalidTestCase<MessageIds, Options>[];
   // RuleTester.run also accepts strings for valid cases
-  readonly valid: readonly (ValidTestCase<Options> | string)[];
+  readonly valid: readonly (string | ValidTestCase<Options>)[];
 }
 
 export interface NormalizedRunTests<

diff --git a/packages/rule-tester/src/utils/flat-config-schema.ts b/packages/rule-tester/src/utils/flat-config-schema.ts
@@ -10,8 +10,8 @@ import { normalizeSeverityToNumber } from './severity';
 type PluginMemberName = `${string}/${string}`;
 
 interface ObjectPropertySchema<T = unknown> {
-  merge: ((a: T, b: T) => T) | string;
-  validate: ((value: unknown) => asserts value is T) | string;
+  merge: string | ((a: T, b: T) => T);
+  validate: string | ((value: unknown) => asserts value is T);
 }
 
 const ruleSeverities = new Map<SharedConfig.RuleLevel, SharedConfig.Severity>([
@@ -279,8 +279,8 @@ const ALLOWED_SEVERITIES = new Set([0, 1, 2, 'error', 'off', 'warn']);
 const disableDirectiveSeveritySchema: ObjectPropertySchema<SharedConfig.RuleLevel> =
   {
     merge(
-      first: SharedConfig.RuleLevel | boolean | undefined,
-      second: SharedConfig.RuleLevel | boolean | undefined,
+      first: boolean | SharedConfig.RuleLevel | undefined,
+      second: boolean | SharedConfig.RuleLevel | undefined,
     ): SharedConfig.RuleLevel {
       const value = second ?? first;
 

diff --git a/packages/scope-manager/src/scope/ScopeBase.ts b/packages/scope-manager/src/scope/ScopeBase.ts
@@ -374,7 +374,7 @@ abstract class ScopeBase<
    * References in default parameters isn't resolved to variables which are in their function body.
    */
   protected defineVariable(
-    nameOrVariable: Variable | string,
+    nameOrVariable: string | Variable,
     set: Map<string, Variable>,
     variables: Variable[],
     node: TSESTree.Identifier | null,

diff --git a/packages/scope-manager/tests/test-utils/getSpecificNode.ts b/packages/scope-manager/tests/test-utils/getSpecificNode.ts
@@ -24,7 +24,7 @@ function getSpecificNode<
 function getSpecificNode(
   ast: TSESTree.Node,
   selector: AST_NODE_TYPES,
-  cb?: (node: TSESTree.Node) => TSESTree.Node | boolean | null | undefined,
+  cb?: (node: TSESTree.Node) => boolean | TSESTree.Node | null | undefined,
 ): TSESTree.Node {
   let node: TSESTree.Node | null | undefined = null;
   simpleTraverse(