eslint.config.mjs

import stylistic from '@stylistic/eslint-plugin'
import typescriptEslint from '@typescript-eslint/eslint-plugin'
import promise from 'eslint-plugin-promise'
import tsParser from '@typescript-eslint/parser'
import path from 'node:path'
import { fileURLToPath } from 'node:url'
import js from '@eslint/js'
import { FlatCompat } from '@eslint/eslintrc'

const __filename = fileURLToPath(import.meta.url)
const __dirname = path.dirname(__filename)
const compat = new FlatCompat({
	baseDirectory: __dirname,
	recommendedConfig: js.configs.recommended,
	allConfig: js.configs.all
})

export default [{
	ignores: ['**/dummy-ext/', '**/test_projects/', '**/esbuild.js'],
}, ...compat.extends(
	'eslint:recommended',
	'plugin:@typescript-eslint/recommended-type-checked',
	'plugin:@typescript-eslint/strict-type-checked',
	'plugin:@typescript-eslint/stylistic-type-checked',
	'plugin:promise/recommended',
), {
	plugins: {
		'@stylistic': stylistic,
		'@typescript-eslint': typescriptEslint,
		promise,
	},

	languageOptions: {
		globals: {
			Atomics: 'readonly',
			SharedArrayBuffer: 'readonly',
		},

		parser: tsParser,
		ecmaVersion: 5,
		sourceType: 'script',

		parserOptions: {
			project: './tsconfig.json',
			tsconfigRootDir: '.',
		},
	},

	rules: {
		'@stylistic/indent': ['error', 'tab'],

		'@stylistic/comma-spacing': ['warn', {
			before: false,
			after: true,
		}],

		'@stylistic/no-extra-parens': 'warn',

		'@typescript-eslint/no-restricted-types': ['error', {
			types: {
				Object: 'Use {} instead.',
				String: 'Use "string" instead.',
				Number: 'Use "number" instead.',
				Boolean: 'Use "boolean" instead.',
			},
		}],

		'@typescript-eslint/naming-convention': ['error', {
			selector: 'interface',
			format: ['PascalCase'],

			custom: {
				regex: '^I[A-Z]',
				match: true,
			},
		}],

		'@typescript-eslint/no-confusing-non-null-assertion': 'warn',

		'@typescript-eslint/no-floating-promises': ['error', {
			checkThenables: true,
		}],

		'@typescript-eslint/no-misused-promises': 'error',
		'@typescript-eslint/no-non-null-assertion': 0,
		'@typescript-eslint/no-unnecessary-condition': 0,
		'no-unused-vars': 'off',

		'@typescript-eslint/no-unused-vars': ['warn', {
			argsIgnorePattern: '^_',
			vars: 'all',
			args: 'none',
			ignoreRestSiblings: false,
		}],

		'@typescript-eslint/prefer-readonly': 'warn',
		'@typescript-eslint/restrict-plus-operands': 'off',
		'@typescript-eslint/switch-exhaustiveness-check': 'warn',
		'promise/catch-or-return': 'warn',
		'promise/no-callback-in-promise': 'off',

		'promise/always-return': ['warn', {
			ignoreLastCallback: true,
		}],

		'no-console': 'warn',
		'no-empty': 'warn',
		'no-mixed-spaces-and-tabs': ['error', 'smart-tabs'],

		'no-trailing-spaces': ['error', {
			skipBlankLines: false,
		}],

		'prefer-promise-reject-errors': 'error',
		quotes: ['warn', 'single'],
		semi: ['error', 'never'],
		'space-before-blocks': ['error', 'always'],
		'space-before-function-paren': ['warn', 'always'],
		'space-in-parens': ['warn', 'never'],

		'spaced-comment': ['error', 'always', {
			markers: ['/'],
		}],
	},
}]