@types/eslint

Linting Configuration

This feature allows you to define and configure ESLint settings using TypeScript. The code sample demonstrates how to set up an ESLint configuration object with various settings like environment, parser, and rules.

const eslintConfig: ESLint.Config = {
  env: {
    browser: true,
    es2021: true
  },
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended'
  ],
  parser: '@typescript-eslint/parser',
  parserOptions: {
    ecmaVersion: 12,
    sourceType: 'module'
  },
  rules: {
    'no-unused-vars': 'warn',
    'semi': ['error', 'always']
  }
};

Linting Programmatically

This feature allows you to run ESLint programmatically using TypeScript. The code sample shows how to create an ESLint instance and lint files, then output the linting results.

import { ESLint } from 'eslint';

const eslint = new ESLint({
  baseConfig: {
    extends: ['eslint:recommended']
  }
});

async function lintFiles(files: string[]) {
  const results = await eslint.lintFiles(files);
  results.forEach(result => {
    console.log(result.filePath);
    result.messages.forEach(msg => console.log(`${msg.line}:${msg.column} ${msg.message}`));
  });
}

lintFiles(['src/**/*.ts']);

Custom ESLint Rules

This feature allows you to define custom ESLint rules using TypeScript. The code sample demonstrates how to create a rule that disallows the use of console statements.

import { Rule } from 'eslint';

const noConsoleRule: Rule.RuleModule = {
  create(context) {
    return {
      CallExpression(node) {
        if (node.callee.type === 'MemberExpression' && node.callee.object.name === 'console') {
          context.report({ node, message: 'Unexpected console statement.' });
        }
      }
    };
  }
};

export default noConsoleRule;