.eslintrc.js

const rushstackEslintConfig = require('@rushstack/eslint-config/profile/node');
const assert = require('assert');
const path = require('path');
const {isDeepStrictEqual} = require('util');

// Rushstack: "This is a workaround for https://github.com/eslint/eslint/issues/3458".
require('@rushstack/eslint-config/patch/modern-module-resolution');

// ESLint configuration is not user-friendly.
const overrides = rushstackEslintConfig.overrides.filter((override) =>
  isDeepStrictEqual(override.files, ['*.ts', '*.tsx']),
);
assert(
  overrides.length === 1,
  "The assumption for locating the .ts override in '@rushstack/eslint-config' is faulty.",
);

module.exports = {
  extends: [
    '@rushstack/eslint-config/profile/node',
    '@rushstack/eslint-config/mixins/tsdoc',
    'plugin:eslint-comments/recommended',
    'plugin:unicorn/recommended',
  ],
  overrides: [
    {
      files: ['types/*.d.ts'],
      rules: {
        // Type files should have the name of the packages that use them, which don't necessarily follow this rule (e.g. `JSONStream`).
        'unicorn/filename-case': 'off',
      },
    },
    {
      files: ['*.ts'],
      rules: {
        '@rushstack/typedef-var': 'off',
        // Rationale: https://github.com/microsoft/rushstack/blob/63777148e110b2d9b690e60d74e58af03d0e7b7e/stack/eslint-config/index.js#L327-L332
        '@typescript-eslint/naming-convention': overrides[0].rules[
          '@typescript-eslint/naming-convention'
        ].map((value) =>
          typeof value === 'object' && value.selector === 'interface'
            ? {format: ['PascalCase'], selector: 'interface'}
            : value,
        ),
      },
    },
    {
      files: ['__mocks__/**/*.ts', 'scripts/jest/*.js', '.eslintrc.js'],
      rules: {
        // Mocks and some configuration files cannot be modules.
        'unicorn/prefer-module': 'off',
        'unicorn/prefer-top-level-await': 'off',
      },
    },
  ],
  parserOptions: {
    project: path.join(__dirname, './tsconfig.eslint.json'),
  },
  rules: {
    'eslint-comments/no-unused-disable': 'error',
    // Can't speak to `chalk`, but on the premise of the others, I disagree.
    'unicorn/import-style': 'off',
    // Since this is covered by 'eslint-comments/no-unlimited-disable'.
    'unicorn/no-abusive-eslint-disable': 'off',
    // The idea is that other development-time checks would tell you if you're referencing an undefined variable, so it won't run if you access it for this comparison.  But I'd rather just avoid that risk altogether.
    'unicorn/no-typeof-undefined': 'off',
    'unicorn/no-unsafe-regex': 'error',
    // Does not work with TypeScript and is not backported to all supported versions of Node.
    'unicorn/prefer-node-protocol': 'off',
  },
};