eslint-config-niieani/src/base.ts

Reusable ESLint config for Beemo configured projects.

/* eslint-disable no-magic-numbers */
/* eslint-disable import/no-commonjs,import/no-import-module-exports */
import type eslint from 'eslint'
import {CASE_SENSITIVE} from '@niieani/scaffold-config-constants'

// The following rules are either overriding Airbnb's defaults,
// or they are enabling new rules that aren't in Airbnb yet.
const config: eslint.Linter.Config = {
  rules: {
    // Use tabs instead of spaces for accessibility
    indent: ['error', 'tab'],
    'no-tabs': 'off',

    // Annoying as some class methods are nice to not be static
    'class-methods-use-this': 'off',

    // Encourage breaking up code when applicable
    complexity: ['error', 11],

    // Allow either kind of comments (docblocks vs inline)
    'multiline-comment-style': 'off',

    // Always prefer object destructuring, but array is optional
    'prefer-destructuring': [
      'error',
      {
        object: true,
        array: false,
      },
    ],

    // Always sort object members for better readability
    'sort-keys': [
      'error',
      'asc',
      {
        caseSensitive: CASE_SENSITIVE,
        natural: true,
      },
    ],

    // Avoid bad or problematic syntax/patterns
    'no-constant-binary-expression': 'error',
    'no-constant-condition': 'error',
    'no-constructor-return': 'error',
    'no-div-regex': 'error',
    'no-dupe-else-if': 'error',
    'no-import-assign': 'error',
    'no-native-reassign': 'error',
    'no-promise-executor-return': 'error',
    'no-setter-return': 'error',
    'no-unreachable-loop': 'error',
    'no-unsafe-optional-chaining': [
      'error',
      {disallowArithmeticOperators: true},
    ],
    'no-unused-private-class-members': 'error',
    'no-useless-call': 'error',
    'require-atomic-updates': 'error',

    // Prefer compact syntax when applicable
    'prefer-exponentiation-operator': 'error',
    'prefer-regex-literals': ['error', {disallowRedundantWrapping: true}],

    // Prefer explicitness for readability
    'no-implicit-coercion': 'error',

    // Encourage reusable constants with descriptive comments
    'no-magic-numbers': [
      'error',
      {
        ignore: [-3, -2, -1, 0, 1, 2, 3, 10, 100, 1_000, 10_000],
        ignoreArrayIndexes: true,
        enforceConst: true,
        // if used from @typescript-eslint/no-magic-numbers:
        // ignoreEnums: true,
        // ignoreNumericLiteralTypes: true,
        // ignoreReadonlyClassProperties: true,
        // ignoreTypeIndexes: true,
      },
    ],

    // Sounds good in practice but is overkill
    'require-unicode-regexp': 'off',

    // Doesnt scope correctly with `this` in arrow functions
    'no-invalid-this': 'off',

    // Allow modern APIs
    'no-restricted-syntax': 'off',

    'prefer-object-has-own': 'error',
  },
}

module.exports = config