feat: add types for flat config files (#7273)

* feat: add types for flat config files

* Update packages/utils/src/ts-eslint/Parser.ts

---------

Co-authored-by: Josh Goldberg ✨ <git@joshuakgoldberg.com>

packages/eslint-plugin-tslint/tests/index.spec.ts

@@ -3,6 +3,8 @@ import { TSESLint } from '@typescript-eslint/utils';
 import { readFileSync } from 'fs';
 import path = require('path');
 
+import type { ClassicConfig } from '@typescript-eslint/utils/ts-eslint';
+
 import type { Options } from '../src/rules/config';
 import rule from '../src/rules/config';
 
@@ -165,7 +167,7 @@ ruleTester.run('tslint/config', rule, {
 });
 
 describe('tslint/error', () => {
-  function testOutput(code: string, config: TSESLint.Linter.Config): void {
+  function testOutput(code: string, config: ClassicConfig.Config): void {
     const linter = new TSESLint.Linter();
     linter.defineRule('tslint/config', rule);
     linter.defineParser('@typescript-eslint/parser', parser);

packages/eslint-plugin/index.d.ts

@@ -1,9 +1,9 @@
-import type { TSESLint } from '@typescript-eslint/utils';
+import type { ClassicConfig } from '@typescript-eslint/utils/ts-eslint';
 
 import type rules from './rules';
 
 declare const cjsExport: {
-  configs: Record<string, TSESLint.Linter.Config>;
+  configs: Record<string, ClassicConfig.Config>;
   rules: typeof rules;
 };
 export = cjsExport;

packages/eslint-plugin/tools/generate-configs.ts

@@ -1,7 +1,12 @@
-import prettier from '@prettier/sync';
-import type { TSESLint } from '@typescript-eslint/utils';
+import type {
+  ClassicConfig,
+  Linter,
+  RuleModule,
+  RuleRecommendation,
+} from '@typescript-eslint/utils/ts-eslint';
 import * as fs from 'fs';
 import * as path from 'path';
+import prettier from 'prettier';
 import * as url from 'url';
 
 import type RulesFile from '../src/rules';
@@ -45,11 +50,11 @@ async function main(): Promise<void> {
     ].join('\n');
   }
 
-  const prettierConfig = prettier.resolveConfig(__dirname);
+  const prettierConfig = await prettier.resolveConfig(__dirname);
 
-  type LinterConfigRules = Record<string, TSESLint.Linter.RuleLevel>;
+  type LinterConfigRules = Record<string, ClassicConfig.RuleLevel>;
 
-  interface LinterConfig extends TSESLint.Linter.Config {
+  interface LinterConfig extends ClassicConfig.Config {
     extends?: string[] | string;
     plugins?: string[];
   }
@@ -74,8 +79,7 @@ async function main(): Promise<void> {
   );
   const EXTENDS = ['./configs/base', './configs/eslint-recommended'];
 
-  // TODO: migrate to import { RuleModule } from '@typescript-eslint/utils/ts-eslint'
-  type RuleEntry = [string, TSESLint.RuleModule<string, readonly unknown[]>];
+  type RuleEntry = [string, RuleModule<string, readonly unknown[]>];
 
   const allRuleEntries: RuleEntry[] = Object.entries(rules).sort((a, b) =>
     a[0].localeCompare(b[0]),
@@ -85,7 +89,7 @@ async function main(): Promise<void> {
     deprecated?: 'exclude';
     typeChecked?: 'exclude' | 'include-only';
     baseRuleForExtensionRule?: 'exclude';
-    forcedRuleLevel?: TSESLint.Linter.RuleLevel;
+    forcedRuleLevel?: Linter.RuleLevel;
   }
 
   /**
@@ -144,13 +148,16 @@ async function main(): Promise<void> {
   /**
    * Helper function writes configuration.
    */
-  function writeConfig(getConfig: () => LinterConfig, name: string): void {
+  async function writeConfig(
+    getConfig: () => LinterConfig,
+    name: string,
+  ): Promise<void> {
     const hyphens = '-'.repeat(35 - Math.ceil(name.length / 2));
     console.log(chalk.blueBright(`\n${hyphens} ${name}.ts ${hyphens}`));
 
     // note: we use `export =` because ESLint will import these configs via a commonjs import
     const code = `export = ${JSON.stringify(getConfig())};`;
-    const configStr = prettier.format(addAutoGeneratedComment(code), {
+    const configStr = await prettier.format(addAutoGeneratedComment(code), {
       parser: 'typescript',
       ...prettierConfig,
     });
@@ -167,13 +174,13 @@ async function main(): Promise<void> {
     ruleEntries: readonly RuleEntry[];
   }
 
-  function writeExtendedConfig({
+  async function writeExtendedConfig({
     extraExtends = [],
     filters: ruleFilter,
     name,
     ruleEntries,
-  }: ExtendedConfigSettings): void {
-    writeConfig(
+  }: ExtendedConfigSettings): Promise<void> {
+    await writeConfig(
       () => ({
         extends: [...EXTENDS, ...extraExtends],
         rules: ruleEntries.reduce(
@@ -186,14 +193,14 @@ async function main(): Promise<void> {
   }
 
   function filterRuleEntriesTo(
-    ...recommendations: (TSESLint.RuleRecommendation | undefined)[]
+    ...recommendations: (RuleRecommendation | undefined)[]
   ): RuleEntry[] {
     return allRuleEntries.filter(([, rule]) =>
       recommendations.includes(rule.meta.docs?.recommended),
     );
   }
 
-  writeConfig((): LinterConfig => {
+  await writeConfig((): LinterConfig => {
     const baseConfig: LinterConfig = {
       parser: '@typescript-eslint/parser',
       parserOptions: {
@@ -215,54 +222,54 @@ async function main(): Promise<void> {
     return baseConfig;
   }, 'base');
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     name: 'all',
     filters: {
       deprecated: 'exclude',
     },
     ruleEntries: allRuleEntries,
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     filters: {
       typeChecked: 'exclude',
     },
     name: 'recommended',
     ruleEntries: filterRuleEntriesTo('recommended'),
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     name: 'recommended-type-checked',
     ruleEntries: filterRuleEntriesTo('recommended'),
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     filters: {
       typeChecked: 'exclude',
     },
     name: 'strict',
     ruleEntries: filterRuleEntriesTo('recommended', 'strict'),
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     name: 'strict-type-checked',
     ruleEntries: filterRuleEntriesTo('recommended', 'strict'),
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     filters: {
       typeChecked: 'exclude',
     },
     name: 'stylistic',
     ruleEntries: filterRuleEntriesTo('stylistic'),
   });
 
-  writeExtendedConfig({
+  await writeExtendedConfig({
     name: 'stylistic-type-checked',
     ruleEntries: filterRuleEntriesTo('stylistic'),
   });
 
-  writeConfig(
+  await writeConfig(
     () => ({
       parserOptions: {
         project: null,

packages/rule-tester/src/RuleTester.ts

@@ -10,6 +10,7 @@ import { deepMerge } from '@typescript-eslint/utils/eslint-utils';
 import type {
   AnyRuleCreateFunction,
   AnyRuleModule,
+  Parser,
   ParserOptions,
   RuleContext,
   RuleModule,
@@ -525,7 +526,7 @@ export class RuleTester extends TestFramework {
 
     this.#linter.defineParser(
       config.parser,
-      wrapParser(require(config.parser) as Linter.ParserModule),
+      wrapParser(require(config.parser) as Parser.ParserModule),
     );
 
     if (schema) {

packages/rule-tester/src/types/RuleTesterConfig.ts

@@ -1,8 +1,11 @@
-import type { Linter, ParserOptions } from '@typescript-eslint/utils/ts-eslint';
+import type {
+  ClassicConfig,
+  ParserOptions,
+} from '@typescript-eslint/utils/ts-eslint';
 
 import type { DependencyConstraint } from './DependencyConstraint';
 
-export interface RuleTesterConfig extends Linter.Config {
+export interface RuleTesterConfig extends ClassicConfig.Config {
   /**
    * The default parser to use for tests.
    * @default '@typescript-eslint/parser'

packages/rule-tester/src/types/ValidTestCase.ts

@@ -1,4 +1,5 @@
 import type {
+  Linter,
   ParserOptions,
   SharedConfigurationSettings,
 } from '@typescript-eslint/utils/ts-eslint';
@@ -17,15 +18,15 @@ export interface ValidTestCase<TOptions extends Readonly<unknown[]>> {
   /**
    * Environments for the test case.
    */
-  readonly env?: Readonly<Record<string, boolean>>;
+  readonly env?: Readonly<Linter.EnvironmentConfig>;
   /**
    * The fake filename for the test case. Useful for rules that make assertion about filenames.
    */
   readonly filename?: string;
   /**
    * The additional global variables.
    */
-  readonly globals?: Record<string, 'off' | 'readonly' | 'writable' | true>;
+  readonly globals?: Readonly<Linter.GlobalsConfig>;
   /**
    * Options for the test case.
    */

packages/rule-tester/src/utils/validationHelpers.ts

@@ -1,6 +1,6 @@
 import { simpleTraverse } from '@typescript-eslint/typescript-estree';
 import type { TSESTree } from '@typescript-eslint/utils';
-import type { Linter, SourceCode } from '@typescript-eslint/utils/ts-eslint';
+import type { Parser, SourceCode } from '@typescript-eslint/utils/ts-eslint';
 
 /*
  * List every parameters possible on a test case that are not related to eslint
@@ -75,7 +75,7 @@ const parserSymbol = Symbol.for('eslint.RuleTester.parser');
  * Wraps the given parser in order to intercept and modify return values from the `parse` and `parseForESLint` methods, for test purposes.
  * In particular, to modify ast nodes, tokens and comments to throw on access to their `start` and `end` properties.
  */
-export function wrapParser(parser: Linter.ParserModule): Linter.ParserModule {
+export function wrapParser(parser: Parser.ParserModule): Parser.ParserModule {
   /**
    * Define `start`/`end` properties of all nodes of the given AST as throwing error.
    */
@@ -121,7 +121,7 @@ export function wrapParser(parser: Linter.ParserModule): Linter.ParserModule {
     return {
       // @ts-expect-error -- see above
       [parserSymbol]: parser,
-      parseForESLint(...args): Linter.ESLintParseResult {
+      parseForESLint(...args): Parser.ParseResult {
         const ret = parser.parseForESLint(...args);
 
         defineStartEndAsErrorInTree(ret.ast, ret.visitorKeys);

packages/scope-manager/src/ScopeManager.ts

@@ -1,4 +1,4 @@
-import type { TSESTree } from '@typescript-eslint/types';
+import type { SourceType, TSESTree } from '@typescript-eslint/types';
 
 import { assert } from './assert';
 import type { Scope } from './scope';
@@ -27,7 +27,7 @@ import type { Variable } from './variable';
 
 interface ScopeManagerOptions {
   globalReturn?: boolean;
-  sourceType?: 'module' | 'script';
+  sourceType?: SourceType;
   impliedStrict?: boolean;
 }
 

packages/scope-manager/src/analyze.ts

@@ -1,4 +1,4 @@
-import type { Lib, TSESTree } from '@typescript-eslint/types';
+import type { Lib, SourceType, TSESTree } from '@typescript-eslint/types';
 import { visitorKeys } from '@typescript-eslint/visitor-keys';
 
 import type { ReferencerOptions } from './referencer';
@@ -55,7 +55,7 @@ interface AnalyzeOptions {
   /**
    * The source type of the script.
    */
-  sourceType?: 'module' | 'script';
+  sourceType?: SourceType;
 
   /**
    * Emit design-type metadata for decorated declarations in source.

packages/types/src/parser-options.ts

@@ -16,21 +16,27 @@ type EcmaVersion =
   | 11
   | 12
   | 13
+  | 14
+  | 15
   | 2015
   | 2016
   | 2017
   | 2018
   | 2019
   | 2020
   | 2021
-  | 2022;
+  | 2022
+  | 2023
+  | 2024;
 
-type SourceType = 'module' | 'script';
+type SourceTypeClassic = 'module' | 'script';
+type SourceType = SourceTypeClassic | 'commonjs';
 
 interface ParserOptions {
   ecmaFeatures?: {
     globalReturn?: boolean;
     jsx?: boolean;
+    [key: string]: unknown;
   };
   ecmaVersion?: EcmaVersion | 'latest';