// Copyright 2018 Signal Messenger, LLC // SPDX-License-Identifier: AGPL-3.0-only // For reference: https://github.com/airbnb/javascript const rules = { 'comma-dangle': [ 'error', { arrays: 'always-multiline', objects: 'always-multiline', imports: 'always-multiline', exports: 'always-multiline', functions: 'never', }, ], // No omitting braces, keep on the same line 'brace-style': ['error', '1tbs', { allowSingleLine: false }], curly: ['error', 'all'], // Immer support 'no-param-reassign': [ 'error', { props: true, ignorePropertyModificationsForRegex: ['^draft'], ignorePropertyModificationsFor: ['acc', 'ctx', 'context'], }, ], // Always use === and !== except when directly comparing to null // (which only will equal null or undefined) eqeqeq: ['error', 'always', { null: 'never' }], // prevents us from accidentally checking in exclusive tests (`.only`): 'mocha/no-exclusive-tests': 'error', // encourage consistent use of `async` / `await` instead of `then` 'more/no-then': 'error', // it helps readability to put public API at top, 'no-use-before-define': 'off', '@typescript-eslint/no-use-before-define': 'off', // useful for unused or internal fields 'no-underscore-dangle': 'off', // Temp: We have because TypeScript's `allowUnreachableCode` option is on. 'no-unreachable': 'error', // though we have a logger, we still remap console to log to disk 'no-console': 'error', // consistently place operators at end of line except ternaries 'operator-linebreak': [ 'error', 'after', { overrides: { '?': 'ignore', ':': 'ignore' } }, ], quotes: [ 'error', 'single', { avoidEscape: true, allowTemplateLiterals: false }, ], 'no-continue': 'off', 'lines-between-class-members': 'off', 'class-methods-use-this': 'off', // Prettier overrides: 'arrow-parens': 'off', 'function-paren-newline': 'off', 'max-len': [ 'error', { // Prettier generally limits line length to 80 but sometimes goes over. // The `max-len` plugin doesn’t let us omit `code` so we set it to a // high value as a buffer to let Prettier control the line length: code: 999, // We still want to limit comments as before: comments: 90, ignoreUrls: true, }, ], 'react/jsx-props-no-spreading': 'off', // Updated to reflect future airbnb standard // Allows for declaring defaultProps inside a class 'react/static-property-placement': ['error', 'static public field'], // JIRA: DESKTOP-657 'react/sort-comp': 'off', // We don't have control over the media we're sharing, so can't require // captions. 'jsx-a11y/media-has-caption': 'off', // We prefer named exports 'import/prefer-default-export': 'off', // Prefer functional components with default params 'react/require-default-props': 'off', // Empty fragments are used in adapters between backbone and react views. 'react/jsx-no-useless-fragment': [ 'error', { allowExpressions: true, }, ], // Our code base has tons of arrow functions passed directly to components. 'react/jsx-no-bind': 'off', // Does not support forwardRef 'react/no-unused-prop-types': 'off', // Not useful for us as we have lots of complicated types. 'react/destructuring-assignment': 'off', 'react/function-component-definition': [ 'error', { namedComponents: 'function-declaration', unnamedComponents: 'arrow-function', }, ], 'react/display-name': 'error', 'react/jsx-pascal-case': ['error', { allowNamespace: true }], // Allow returning values from promise executors for brevity. 'no-promise-executor-return': 'off', // Redux ducks use this a lot 'default-param-last': 'off', 'jsx-a11y/label-has-associated-control': ['error', { assert: 'either' }], 'jsx-a11y/no-static-element-interactions': 'error', '@typescript-eslint/no-non-null-assertion': ['error'], '@typescript-eslint/no-empty-interface': ['error'], 'no-empty-function': 'off', '@typescript-eslint/no-empty-function': 'error', 'no-restricted-syntax': [ 'error', { selector: 'TSInterfaceDeclaration', message: 'Prefer `type`. Interfaces are mutable and less powerful, so we prefer `type` for simplicity.', }, // Defaults { selector: 'ForInStatement', message: 'for..in loops iterate over the entire prototype chain, which is virtually never what you want. Use Object.{keys,values,entries}, and iterate over the resulting array.', }, { selector: 'LabeledStatement', message: 'Labels are a form of GOTO; using them makes code confusing and hard to maintain and understand.', }, { selector: 'WithStatement', message: '`with` is disallowed in strict mode because it makes code impossible to predict and optimize.', }, ], 'react-hooks/exhaustive-deps': [ 'error', { additionalHooks: '^(useSpring|useSprings)$', }, ], }; const typescriptRules = { ...rules, // Override brace style to enable typescript-specific syntax 'brace-style': 'off', '@typescript-eslint/brace-style': [ 'error', '1tbs', { allowSingleLine: false }, ], '@typescript-eslint/array-type': ['error', { default: 'generic' }], 'no-restricted-imports': 'off', '@typescript-eslint/no-restricted-imports': [ 'error', { paths: [ { name: 'chai', importNames: ['expect', 'should', 'Should'], message: 'Please use assert', allowTypeImports: true, }, ], }, ], // Overrides recommended by typescript-eslint // https://github.com/typescript-eslint/typescript-eslint/releases/tag/v4.0.0 '@typescript-eslint/no-redeclare': 'error', '@typescript-eslint/no-shadow': 'error', '@typescript-eslint/no-useless-constructor': ['error'], '@typescript-eslint/no-misused-promises': [ 'error', { checksVoidReturn: false, }, ], '@typescript-eslint/no-floating-promises': 'error', // We allow "void promise", but new call-sites should use `drop(promise)`. 'no-void': ['error', { allowAsStatement: true }], 'no-shadow': 'off', 'no-useless-constructor': 'off', // useful for unused parameters '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_' }], // Upgrade from a warning '@typescript-eslint/explicit-module-boundary-types': 'error', '@typescript-eslint/consistent-type-imports': 'error', // Future: Maybe switch to never and always use `satisfies` '@typescript-eslint/consistent-type-assertions': [ 'error', { assertionStyle: 'as', // Future: Maybe switch to allow-as-parameter or never objectLiteralTypeAssertions: 'allow', }, ], // Already enforced by TypeScript 'consistent-return': 'off', // TODO: DESKTOP-4655 'import/no-cycle': 'off', }; module.exports = { root: true, settings: { react: { version: 'detect', }, 'import/core-modules': ['electron'], }, extends: ['airbnb-base', 'prettier'], plugins: ['mocha', 'more', 'local-rules'], overrides: [ { files: [ 'ts/**/*.ts', 'ts/**/*.tsx', 'app/**/*.ts', 'build/intl-linter/**/*.ts', ], parser: '@typescript-eslint/parser', parserOptions: { project: 'tsconfig.json', ecmaFeatures: { jsx: true, }, ecmaVersion: 2018, sourceType: 'module', }, plugins: ['@typescript-eslint'], extends: [ 'eslint:recommended', 'plugin:@typescript-eslint/recommended', 'plugin:react/recommended', 'airbnb-typescript-prettier', ], rules: typescriptRules, }, { files: [ '**/*.stories.tsx', 'ts/build/**', 'ts/test-*/**', 'build/intl-linter/**/*.ts', ], rules: { ...typescriptRules, 'import/no-extraneous-dependencies': 'off', 'react/no-array-index-key': 'off', }, }, { files: ['ts/state/ducks/**/*.ts'], rules: { 'local-rules/type-alias-readonlydeep': 'error', }, }, { files: ['ts/**/*_test.{ts,tsx}'], rules: { 'func-names': 'off', }, }, ], rules: { ...rules, 'import/no-unresolved': 'off', 'import/extensions': 'off', }, reportUnusedDisableDirectives: true, };