eslint.config.mjs

import pluginJs from '@eslint/js'
import stylistic from '@stylistic/eslint-plugin'
import { AST_NODE_TYPES } from '@typescript-eslint/utils'
import 'eslint-plugin-only-warn'
import globals from 'globals'
import tseslint from 'typescript-eslint'
import noBlankLinesInOptionalBlocks from './rule/no-blank-lines-in-optional-blocks.mjs'
import noUnusedExpressions from './rule/no-unused-expressions.mjs'

/** @import {TSESLint} from "@typescript-eslint/utils" */

/** @type {(root: string) => TSESLint.Linter.ConfigType[]} */
export function config (root) {
	return [
		{ files: ['**/*.{js,mjs,cjs,ts}'] },
		{ languageOptions: { globals: { ...globals.browser, ...globals.node } } },
		pluginJs.configs.recommended,
		...tseslint.configs.recommendedTypeChecked,

		{
			languageOptions: {
				parserOptions: {
					projectService: true,
					tsconfigRootDir: root,
				},
			},
		},

		stylistic.configs.customize({
			indent: 'tab',
			quotes: 'single',
			semi: false,
			jsx: false,
		}),

		{
			rules: {
				'no-constant-binary-expression': 'off',
				'no-empty': ['warn', { allowEmptyCatch: true }],
				'no-constant-condition': ['warn', { checkLoops: false }],
				'prefer-const': ['warn', { destructuring: 'all' }],
				'no-irregular-whitespace': ['warn', { skipRegExps: true }],

				'@typescript-eslint/no-explicit-any': 'off',
				'@typescript-eslint/no-namespace': 'off',
				'@typescript-eslint/consistent-type-imports': 'warn',
				'@typescript-eslint/no-unused-expressions': 'off',
				'@typescript-eslint/no-unused-vars': ['warn', { argsIgnorePattern: '.', varsIgnorePattern: '^[A-Z_]+$' }],
				'@typescript-eslint/no-unsafe-declaration-merging': 'off',
				'@typescript-eslint/unbound-method': 'off',
				'@typescript-eslint/no-empty-object-type': ['warn', { allowInterfaces: 'always' }],

				'@stylistic/no-trailing-spaces': 'off', // removed by typescript
				'@stylistic/indent': 'off',
				'@stylistic/indent-binary-ops': 'off',
				'@stylistic/multiline-ternary': 'off',
				'@stylistic/spaced-comment': ['warn', 'always', { exceptions: ['/'], markers: ['#region', '#endregion'] }],
				'@stylistic/space-before-function-paren': ['warn', 'always'],
				'@stylistic/quotes': ['warn', 'single'],
				'@stylistic/padded-blocks': ['warn', { blocks: 'never', classes: 'always' }],
				'@stylistic/arrow-parens': ['warn', 'as-needed'],
				'@stylistic/comma-dangle': ['warn', {
					arrays: 'always-multiline',
					objects: 'always-multiline',
					imports: 'always-multiline',
					exports: 'always-multiline',
					enums: 'always-multiline',
					tuples: 'always-multiline',
					generics: 'ignore',
					functions: 'ignore',
				}],
				'@stylistic/eol-last': ['warn', 'always'],
				'@stylistic/max-statements-per-line': ['warn', {
					ignoredNodes: [
						AST_NODE_TYPES.BreakStatement,
						AST_NODE_TYPES.ExpressionStatement,
						AST_NODE_TYPES.ReturnStatement,
					],
				}],
				'@stylistic/padding-line-between-statements': [
					'warn',
					{ blankLine: 'never', prev: 'block', next: '*' },
				],
			},
		},

		{
			plugins: {
				fluff: {
					rules: {
						...noUnusedExpressions,
						...noBlankLinesInOptionalBlocks,
					},
				},
			},
			rules: {
				'fluff/no-unused-expressions': 'warn',
				'fluff/no-blank-lines-in-optional-blocks': 'warn',
			},
		},
	]
}

export default config(import.meta.dirname)