.eslintrc.js

/**
 * initial setup with npm init @eslint/config
 * (typescript, custom rules)
 */
module.exports = {
    env: {
        browser: true,
        es2021: true,
    },
    extends: [
        'eslint:recommended',
        'plugin:@typescript-eslint/recommended',
        'plugin:react/recommended',
        'plugin:@next/next/recommended',
    ],
    settings: {
        react: {
            version: 'detect',
        },
    },
    overrides: [
        {
            env: {
                node: true,
            },
            files: [
                '.eslintrc.{js,cjs}',
            ],
            parserOptions: {
                sourceType: 'script',
            },
        },
    ],
    parser: '@typescript-eslint/parser',
    parserOptions: {
        ecmaVersion: 'latest',
        sourceType: 'module',
    },
    plugins: [
        '@typescript-eslint',
        'react',
    ],
    rules: {
        indent: [
            'error',
            4,
        ],
        'linebreak-style': [
            'error',
            'unix',
        ],
        quotes: [
            'error',
            'single',
        ],
        semi: [
            'error',
            'always',
        ],
        'no-trailing-spaces': 'error',
        'no-multi-spaces': 'error',
        'quote-props': ['error', 'as-needed'],
        'comma-dangle': ['error', 'always-multiline'],
        'object-curly-spacing': ['error', 'always'],
        'react/react-in-jsx-scope': 'off',
        'eol-last': ['error', 'always'],
    },
};