@typescript-eslint/typescript-estree 8.x

Complete instructions

Verified against @typescript-eslint/typescript-estree@8.70.0 on 2026-09-08. 3 of 3 examples executed.

@typescript-eslint/typescript-estree

What this package does

@typescript-eslint/typescript-estree converts TypeScript source text into an ESTree-compatible AST. Its documented public surface includes:

• parse(code, options), returning a TSESTree.Program.
• parseAndGenerateServices(code, options), returning an AST plus parser services.
• createProgram(configFile, projectDirectory?), a helper for creating a TypeScript Program for the programs option.
• TSESTree, the namespace of AST node types.
• AST_NODE_TYPES and AST_TOKEN_TYPES, whose values are used by AST nodes and tokens.

The v8 package requires Node ^18.18.0 || ^20.9.0 || >=21.1.0 and TypeScript >=4.8.4 <5.5.0. Its documented ESLint minimum is ^8.57.0.

Basic parsing

Use parse when an ESTree-compatible AST is enough:

import { strict as assert } from 'node:assert';
import { parse } from '@typescript-eslint/typescript-estree';

const ast = parse(`const hello: string = 'world';`, {
  loc: true,
  range: true,
});

assert.equal(ast.type, 'Program');
assert.equal(ast.body.length, 1);
assert.equal(ast.range?.[0], 0);
assert.ok(ast.loc);

loc: true adds source locations and range: true adds character ranges. The returned value is a TSESTree.Program.

AST type and token constants

Use AST_NODE_TYPES and AST_TOKEN_TYPES rather than copying string values when comparing AST types or token types:

import { strict as assert } from 'node:assert';
import {
  parse,
  AST_NODE_TYPES,
  AST_TOKEN_TYPES,
} from '@typescript-eslint/typescript-estree';

const ast = parse('const answer = 42;');

assert.equal(ast.type, AST_NODE_TYPES.Program);
assert.equal(AST_TOKEN_TYPES.Identifier, 'Identifier');

TSESTree is a TypeScript namespace of AST node types rather than a value to inspect at runtime.

Parser services

Use parseAndGenerateServices when the caller needs the AST together with parser services. The documented service surface includes program, esTreeNodeToTSNodeMap, and tsNodeToESTreeNodeMap when configured for type information.

import { strict as assert } from 'node:assert';
import { parseAndGenerateServices } from '@typescript-eslint/typescript-estree';

const { ast, services } = parseAndGenerateServices(
  `const hello: string = 'world';`,
  {
    filePath: 'example.ts',
    loc: true,
    range: true,
  },
);

assert.equal(ast.type, 'Program');
assert.ok(services);
assert.ok(ast.loc);
assert.ok(ast.range);

Plain parsing does not provide type information. Type-aware parsing requires a project, projectService, or supplied programs; rules that need type information cannot obtain it from parse() alone.

Supplying a TypeScript program

createProgram(configFile, projectDirectory?) creates a TypeScript Program from a TSConfig and is documented as a helper for the programs option:

const program = tsESTree.createProgram('tsconfig.json');
const { ast, services } = parseAndGenerateServices(code, {
  filePath: '/some/path/to/file/foo.ts',
  program,
});

This requires a real TSConfig/project and is therefore not a standalone in-memory operation. filePath identifies the source file for project-aware parsing.

v8 migration traps

• Do not use parserOptions.EXPERIMENTAL_useProjectService; in v8 the stable name is parserOptions.projectService.
• parserOptions.project remains available, but v8 documentation prefers projectService.
• Do not use the removed DEPRECATED__createDefaultProgram isolated-program support. Migrate to projectService or project.
• Do not use the removed EXPERIMENTAL_useSourceOfProjectReferenceRedirect; use projectService.
• The option formerly named automaticSingleRunInference is now disallowAutomaticSingleRunInference. Its default is opt-out.
• Project globs match dot-directories by default in v8.

projectService is tied to TypeScript project/TSConfig discovery, not just a source string. Its documented configuration includes allowDefaultProject, defaultProject, and loadTypeScriptPlugins, for example:

projectService: {
  allowDefaultProject: ['*.js'],
  defaultProject: 'tsconfig.json',
  loadTypeScriptPlugins: false,
}

The project service can create persistent file watchers. It defaults to false specifically to avoid operations that prevent CLI processes from exiting.

What this skill does not cover

This skill does not cover the complete export list, the full ParseOptions schema, detailed AST node shapes, TypeScript compiler APIs, or the surrounding ESLint parser configuration. It also does not provide a runnable project-service or createProgram example because those require a TSConfig/project and filesystem-backed project discovery. The research does not document how to configure every type-aware option or every parser-service mapping operation.