Apr 11, 2025 · Feb 3, 2025 · Feb 3, 2025 · Feb 4, 2025 · Mar 7, 2025 · Mar 7, 2025
diff --git a/.gitignore b/.gitignore

 .nx/cache
 .nx/workspace-data

 # Vitest type tests
 tsconfig*.vitest-temp.json
diff --git a/eslint.config.mjs b/eslint.config.mjs
  'packages/visitor-keys/tests/**/*.test.{ts,tsx,cts,mts}',
  'packages/parser/tests/lib/**/*.test.{ts,tsx,cts,mts}',
  'packages/parser/tests/test-utils/**/*.{ts,tsx,cts,mts}',
  'packages/utils/tests/**/*.test?(-d).{ts,tsx,cts,mts}',
 ];

 export default tseslint.config(
diff --git a/knip.ts b/knip.ts
    },
    'packages/utils': {
      ignore: [
        'tests/**/*.type-test.ts',
        'typings/eslint.d.ts',
        'typings/eslint-community-eslint-utils.d.ts',
      ],
diff --git a/packages/utils/jest.config.js b/packages/utils/jest.config.js
diff --git a/packages/utils/package.json b/packages/utils/package.json
    "build": "tsc -b tsconfig.build.json",
    "postbuild": "downlevel-dts dist _ts4.3/dist --to=4.3",
    "clean": "tsc -b tsconfig.build.json --clean",
    "postclean": "rimraf dist && rimraf _ts3.4 && rimraf_ts4.3 && rimrafcoverage",
    "postclean": "rimraf dist/_ts4.3/coverage/",
    "format": "prettier --write \"./**/*.{ts,mts,cts,tsx,js,mjs,cjs,jsx,json,md,css}\" --ignore-path ../../.prettierignore",
    "lint": "npx nx lint",
    "test": "jest",
    "test": "vitest --run --config=$INIT_CWD/vitest.config.mts",
    "check-types": "npx nx typecheck"
  },
  "dependencies": {
    "typescript": ">=4.8.4 <5.9.0"
  },
  "devDependencies": {
    "@vitest/coverage-v8": "^3.1.1",
    "downlevel-dts": "*",
    "jest": "29.7.0",
    "prettier": "^3.2.5",
    "rimraf": "*",
    "typescript": "*"
    "typescript": "*",
    "vitest": "^3.1.1"
  },
  "funding": {
    "type": "opencollective",
diff --git a/packages/utils/project.json b/packages/utils/project.json
 {
  "name": "utils",
  "$schema": "../../node_modules/nx/schemas/project-schema.json",
  "type": "library",
  "implicitDependencies": [],
  "projectType": "library",
  "root": "packages/utils",
  "sourceRoot": "packages/utils/src",
  "targets": {
    "lint": {
      "executor": "@nx/eslint:lint",
      "outputs": ["{options.outputFile}"]
    },
    "test": {
      "executor": "@nx/vite:test",
      "dependsOn": ["^build", "typecheck"]
    }
  }
 }
diff --git a/packages/utils/tests/eslint-utils/RuleCreator.test.ts b/packages/utils/tests/eslint-utils/RuleCreator.test.ts
 import { ESLintUtils } from '../../src';

 describe('RuleCreator', () => {
 describe(ESLintUtils.RuleCreator, () => {
  interface TestDocs {
    recommended?: 'yes';
  }

  const createRule = ESLintUtils.RuleCreator<TestDocs>(name => `test/${name}`);

  it('createRule should be a function', () => {
    expect(typeofcreateRule).toBe('function');
    expect(createRule).toBeTypeOf('function');
  });

  it('should create rule correctly', () => {
diff --git a/packages/utils/tests/eslint-utils/applyDefault.test.ts b/packages/utils/tests/eslint-utils/applyDefault.test.ts
 import { ESLintUtils } from '../../src';

 describe('applyDefault', () => {
 describe(ESLintUtils.applyDefault, () => {
  it('returns a clone of the default if no options given', () => {
    const defaults = [{ prop: 'setting' }];
    const user = null;
diff --git a/packages/utils/tests/eslint-utils/deepMerge.test.ts b/packages/utils/tests/eslint-utils/deepMerge.test.ts
 import { ESLintUtils } from '../../src';

 describe('deepMerge', () => {
 describe(ESLintUtils.deepMerge, () => {
  it('creates a brand new object', () => {
    const a = {};
    const b = {};
diff --git a/packages/utils/tests/eslint-utils/getParserServices.test.ts b/packages/utils/tests/eslint-utils/getParserServices.test.ts
 /* eslint-disable @typescript-eslint/no-explicit-any -- wild and wacky testing */
 import type * as ts from 'typescript';

 import type { ParserServices, TSESLint, TSESTree } from '../../src';
 Note: detected a parser other than @typescript-eslint/parser. Make sure the parser is configured to forward "parserOptions.project" to @typescript-eslint/parser.`,
  );

 describe('getParserServices', () => {
 describe(ESLintUtils.getParserServices, () => {
  it('throws a standard error with the parser when parserOptions.esTreeNodeToTSNodeMap is missing and the parser is typescript-eslint', () => {
    const context = createMockRuleContext({
      sourceCode: {
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          esTreeNodeToTSNodeMap: undefined as any,
          esTreeNodeToTSNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          esTreeNodeToTSNodeMap: undefined as any,
          esTreeNodeToTSNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          esTreeNodeToTSNodeMap: undefined as any,
          esTreeNodeToTSNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          esTreeNodeToTSNodeMap: undefined as any,
          esTreeNodeToTSNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          esTreeNodeToTSNodeMap: undefined as any,
          esTreeNodeToTSNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          tsNodeToESTreeNodeMap: undefined as any,
          tsNodeToESTreeNodeMap: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          program: undefined as any,
          program: undefined,
        },
      },
    });
        ...defaults.sourceCode,
        parserServices: {
          ...defaults.sourceCode.parserServices,
          program: undefined as any,
          program: undefined,
        },
      },
    });
diff --git a/packages/utils/tests/eslint-utils/nullThrows.test.ts b/packages/utils/tests/eslint-utils/nullThrows.test.ts
 import { nullThrows, NullThrowsReasons } from '../../src/eslint-utils';

 describe('nullThrows', () => {
 describe(nullThrows, () => {
  it('returns a falsy value when it exists', () => {
    const value = 0;

diff --git a/packages/utils/tests/eslint-utils/parserSeemsToBeTSESLint.test.ts b/packages/utils/tests/eslint-utils/parserSeemsToBeTSESLint.test.ts
 import { parserSeemsToBeTSESLint } from '../../src/eslint-utils/parserSeemsToBeTSESLint';

 describe('parserSeemsToBeTSESLint', () => {
  test.each([
 describe(parserSeemsToBeTSESLint, () => {
  test.for([
    [undefined, false],
    ['espree', false],
    ['local.js', false],
    ['/path/to/typescript-eslint/packages/parser/index.js', true],
    ['/path/to/@typescript-eslint/packages/parser/dist/index.js', true],
    ['/path/to/@typescript-eslint/packages/parser/index.js', true],
  ])('%s', (parserPath, expected) => {
  ] as const)('%s', ([parserPath, expected], { expect }) => {
    expect(parserSeemsToBeTSESLint(parserPath)).toBe(expected);
  });
 });
diff --git a/...s/utils/tests/ts-eslint/Rule.type-test.ts → ...ages/utils/tests/ts-eslint/Rule.test-d.ts b/...s/utils/tests/ts-eslint/Rule.type-test.ts → ...ages/utils/tests/ts-eslint/Rule.test-d.ts
  | `${TSESTree.AST_NODE_TYPES}:exit`
  | `${TSESTree.AST_NODE_TYPES}`;

 type ExpectNever<T extends never> = T;

 type SelectorsWithWrongNodeType = {
  [K in TSESTree.AST_NODE_TYPES]: Parameters<
    NonNullable<RuleListener[K]>
      : K
    : K;
 }[TSESTree.AST_NODE_TYPES];
 type _test_rule_listener_selectors_have_correct_node_types =
  ExpectNever<SelectorsWithWrongNodeType>;

 type ExtraSelectors = Exclude<RuleListenerSelectors, AllSelectors>;
 type _test_rule_listener_does_not_define_extra_selectors =
  ExpectNever<ExtraSelectors>;
 test('type tests', () => {
  expectTypeOf<SelectorsWithWrongNodeType>().toBeNever();

  expectTypeOf<RuleListenerSelectors>().exclude<AllSelectors>().toBeNever();

 type MissingSelectors = Exclude<AllSelectors, RuleListenerSelectors>;
 type _test_rule_listener_has_selectors_for_all_node_types =
  ExpectNever<MissingSelectors>;
  expectTypeOf<AllSelectors>().exclude<RuleListenerSelectors>().toBeNever();
 });
diff --git a/packages/utils/tsconfig.build.json b/packages/utils/tsconfig.build.json
  },
  "include": ["src/**/*.ts", "typings"],
  "exclude": [
    "jest.config.js",
    "vitest.config.mts",
    "src/**/*.spec.ts",
    "src/**/*.test.ts",
    "**/fixtures/**"
diff --git a/packages/utils/tsconfig.spec.json b/packages/utils/tsconfig.spec.json
  "compilerOptions": {
    "outDir": "../../dist/out-tsc/packages/utils",
    "module": "NodeNext",
    "types": ["jest", "node"]
    "resolveJsonModule": true,
    "types": ["node", "vitest/globals", "vitest/importMeta"]
  },
  "include": [
    "jest.config.js",
    "vitest.config.mts",
    "package.json",
    "src/**/*.test.ts",
    "src/**/*.spec.ts",
    "src/**/*.d.ts",
  "references": [
    {
      "path": "./tsconfig.build.json"
    },
    {
      "path": "../../tsconfig.spec.json"
    }
  ]
 }
diff --git a/packages/utils/vitest.config.mts b/packages/utils/vitest.config.mts
 import * as path from 'node:path';
 import { defineProject, mergeConfig } from 'vitest/config';

 import { vitestBaseConfig } from '../../vitest.config.base.mjs';
 import packageJson from './package.json' with { type: 'json' };

 const vitestConfig = mergeConfig(
  vitestBaseConfig,

  defineProject({
    root: import.meta.dirname,

    test: {
      dir: path.join(import.meta.dirname, 'tests'),
      name: packageJson.name.replace('@typescript-eslint/', ''),
      root: import.meta.dirname,

      typecheck: {
        enabled: true,
        tsconfig: path.join(import.meta.dirname, 'tsconfig.spec.json'),
      },
    },
  }),
 );

 export default vitestConfig;
diff --git a/yarn.lock b/yarn.lock
    "@typescript-eslint/scope-manager": 8.29.1
    "@typescript-eslint/types": 8.29.1
    "@typescript-eslint/typescript-estree": 8.29.1
    "@vitest/coverage-v8": ^3.1.1
    downlevel-dts: "*"
    jest: 29.7.0
    prettier: ^3.2.5
    rimraf: "*"
    typescript: "*"
    vitest: ^3.1.1
  peerDependencies:
    eslint: ^8.57.0 || ^9.0.0
    typescript: ">=4.8.4 <5.9.0"
Original file line number	Diff line number	Diff line change
Expand Up		@@ -99,3 +99,6 @@ packages/**/.yarn

		.nx/cache
		.nx/workspace-data

		# Vitest type tests
		tsconfig*.vitest-temp.json
Original file line number	Diff line number	Diff line change
Expand Up		@@ -35,6 +35,7 @@ const vitestFiles = [
		'packages/visitor-keys/tests/*/.test.{ts,tsx,cts,mts}',
		'packages/parser/tests/lib/*/.test.{ts,tsx,cts,mts}',
		'packages/parser/tests/test-utils/*/.{ts,tsx,cts,mts}',
		'packages/utils/tests/*/.test?(-d).{ts,tsx,cts,mts}',
		];

		export default tseslint.config(
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -86,7 +86,6 @@ export default {
		},
		'packages/utils': {
		ignore: [
		'tests/*/.type-test.ts',
		'typings/eslint.d.ts',
		'typings/eslint-community-eslint-utils.d.ts',
		],
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -57,10 +57,10 @@
		"build": "tsc -b tsconfig.build.json",
		"postbuild": "downlevel-dts dist _ts4.3/dist --to=4.3",
		"clean": "tsc -b tsconfig.build.json --clean",
		"postclean": "rimraf dist && rimraf _ts3.4 && rimraf_ts4.3 && rimrafcoverage",
		"postclean": "rimraf dist/_ts4.3/coverage/",
		"format": "prettier --write \"./*/.{ts,mts,cts,tsx,js,mjs,cjs,jsx,json,md,css}\" --ignore-path ../../.prettierignore",
		"lint": "npx nx lint",
		"test": "jest",
		"test": "vitest --run --config=$INIT_CWD/vitest.config.mts",
		"check-types": "npx nx typecheck"
		},
		"dependencies": {
Expand All		@@ -74,11 +74,12 @@
		"typescript": ">=4.8.4 <5.9.0"
		},
		"devDependencies": {
		"@vitest/coverage-v8": "^3.1.1",
		"downlevel-dts": "*",
		"jest": "29.7.0",
		"prettier": "^3.2.5",
		"rimraf": "*",
		"typescript": "*"
		"typescript": "*",
		"vitest": "^3.1.1"
		},
		"funding": {
		"type": "opencollective",
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,12 +1,17 @@
		{
		"name": "utils",
		"$schema": "../../node_modules/nx/schemas/project-schema.json",
		"type": "library",
		"implicitDependencies": [],
		"projectType": "library",
		"root": "packages/utils",
		"sourceRoot": "packages/utils/src",
		"targets": {
		"lint": {
		"executor": "@nx/eslint:lint",
		"outputs": ["{options.outputFile}"]
		},
		"test": {
		"executor": "@nx/vite:test",
		"dependsOn": ["^build", "typecheck"]
		}
		}
		}
Original file line number	Diff line number	Diff line change
		@@ -1,14 +1,14 @@
		import { ESLintUtils } from '../../src';

		describe('RuleCreator', () => {
		describe(ESLintUtils.RuleCreator, () => {
		interface TestDocs {
		recommended?: 'yes';
		}

		const createRule = ESLintUtils.RuleCreator<TestDocs>(name => `test/${name}`);

		it('createRule should be a function', () => {
		expect(typeofcreateRule).toBe('function');
		expect(createRule).toBeTypeOf('function');
		});

		it('should create rule correctly', () => {
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,6 +1,6 @@
		import { ESLintUtils } from '../../src';

		describe('applyDefault', () => {
		describe(ESLintUtils.applyDefault, () => {
		it('returns a clone of the default if no options given', () => {
		const defaults = [{ prop: 'setting' }];
		const user = null;
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,6 +1,6 @@
		import { ESLintUtils } from '../../src';

		describe('deepMerge', () => {
		describe(ESLintUtils.deepMerge, () => {
		it('creates a brand new object', () => {
		const a = {};
		const b = {};
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,4 +1,3 @@
		/* eslint-disable @typescript-eslint/no-explicit-any -- wild and wacky testing */
		import type * as ts from 'typescript';

		import type { ParserServices, TSESLint, TSESTree } from '../../src';
Expand DownExpand Up		@@ -38,14 +37,14 @@ const unknownParserErrorRegex = (parser?: string): RegExp =>
		Note: detected a parser other than @typescript-eslint/parser. Make sure the parser is configured to forward "parserOptions.project" to @typescript-eslint/parser.`,
		);

		describe('getParserServices', () => {
		describe(ESLintUtils.getParserServices, () => {
		it('throws a standard error with the parser when parserOptions.esTreeNodeToTSNodeMap is missing and the parser is typescript-eslint', () => {
		const context = createMockRuleContext({
		sourceCode: {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		esTreeNodeToTSNodeMap: undefined as any,
		esTreeNodeToTSNodeMap: undefined,
		},
		},
		});
Expand All		@@ -69,7 +68,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		esTreeNodeToTSNodeMap: undefined as any,
		esTreeNodeToTSNodeMap: undefined,
		},
		},
		});
Expand All		@@ -87,7 +86,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		esTreeNodeToTSNodeMap: undefined as any,
		esTreeNodeToTSNodeMap: undefined,
		},
		},
		});
Expand All		@@ -107,7 +106,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		esTreeNodeToTSNodeMap: undefined as any,
		esTreeNodeToTSNodeMap: undefined,
		},
		},
		});
Expand All		@@ -124,7 +123,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		esTreeNodeToTSNodeMap: undefined as any,
		esTreeNodeToTSNodeMap: undefined,
		},
		},
		});
Expand All		@@ -139,7 +138,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		tsNodeToESTreeNodeMap: undefined as any,
		tsNodeToESTreeNodeMap: undefined,
		},
		},
		});
Expand All		@@ -155,7 +154,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		program: undefined as any,
		program: undefined,
		},
		},
		});
Expand All		@@ -171,7 +170,7 @@ describe('getParserServices', () => {
		...defaults.sourceCode,
		parserServices: {
		...defaults.sourceCode.parserServices,
		program: undefined as any,
		program: undefined,
		},
		},
		});
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,6 +1,6 @@
		import { nullThrows, NullThrowsReasons } from '../../src/eslint-utils';

		describe('nullThrows', () => {
		describe(nullThrows, () => {
		it('returns a falsy value when it exists', () => {
		const value = 0;

Expand Down