@typescript-eslint/types

What is @typescript-eslint/types?

The @typescript-eslint/types package is part of the TypeScript-ESLint project, which provides a TypeScript parser for ESLint and utilities for working with TypeScript and ESLint together. This specific package contains TypeScript definitions for ESLint-specific types, making it easier to work with ESLint configurations, rules, and plugins in a TypeScript environment. It is primarily used by developers who are creating custom ESLint rules or configurations and want to leverage TypeScript's type-checking capabilities for better development experience.

What are @typescript-eslint/types's main functionalities?

AST Node Types

Provides TypeScript interfaces for AST nodes generated by the parser. This is useful for writing type-safe code that inspects or manipulates the AST, such as custom ESLint rules.

import { TSESTree } from '@typescript-eslint/types';

function processNode(node: TSESTree.Node) {
  if (node.type === 'Identifier') {
    console.log('Found an identifier:', node.name);
  }
}

Rule Definition Helpers

Includes types for defining ESLint rules in a TypeScript-friendly way, making it easier to create custom rules with type safety.

import { TSESLint } from '@typescript-eslint/types';

const myRule: TSESLint.RuleModule<'my-error', []> = {
  meta: {
    type: 'problem',
    docs: {
      description: 'My custom rule',
      recommended: 'error'
    }
  },
  create(context) {
    return {
      Identifier(node) {
        context.report({
          node,
          messageId: 'my-error'
        });
      }
    };
  }
};

Other packages similar to @typescript-eslint/types

@typescript-eslint/experimental-utils

This package provides a set of utilities for working with TypeScript and ESLint, including ESLint rule helpers and AST utilities. It is similar to @typescript-eslint/types but offers a broader range of tools for rule development and AST manipulation.

eslint-plugin-typescript

An older package that aimed to add TypeScript support to ESLint before the official @typescript-eslint project was established. It provides some similar functionalities but is now deprecated in favor of the more comprehensive and up-to-date @typescript-eslint suite of packages.

README

TypeScript-ESTree Types

This package exists to help us reduce cycles and provide lighter-weight packages at runtime. You probably don't want to use it directly.

If you're building an ESLint plugin, consider using @typescript-eslint/utils. If you're parsing TypeScript code, consider using @typescript-eslint/typescript-estree.

Contributing

See the contributing guide here

Changelog

5.26.0 (2022-05-23)

Bug Fixes

• ast-spec: add SpreadElement to ArrayExpression.elements (#5025) (9f3121b)
• eslint-plugin: [member-delimiter-style] autofixer result is not as expected when comments after the delimiter with option delimiter: 'none' (#5029) (ed7b5f6)
• eslint-plugin: [member-delimiter-style] autofixer result is not as expected with option delimiter: 'none' (#5023) (9e97a11)
• eslint-plugin: [prefer-readonly] correct issue with anonymus functions (#4974) (952e2f0), closes #2590

Features

• [4.7] support instantiation expressions (#4938) (79fbc77)
• [4.7] support optional variance annotation (#4831) (7e7b24c)
• typescript-estree: extends constraints for infer (#4830) (8cbbcc3)