.eslintrc.yml

---
root: true

parser: babel-eslint
extends:
  # https://github.com/yannickcr/eslint-plugin-react
  - plugin:react/recommended
  # https://github.com/gajus/eslint-plugin-flowtype
  - plugin:flowtype/recommended
  # https://www.npmjs.com/package/eslint-plugin-jest
  - plugin:jest/recommended
  # https://www.npmjs.com/package/eslint-config-airbnb-base
  - airbnb
  # https://github.com/prettier/eslint-config-prettier
  - prettier
  - prettier/flowtype
  - prettier/react

plugins:
  - react
  - import
  - jest
  - flowtype
  # https://github.com/prettier/eslint-plugin-prettier
  - prettier

settings:
  flowtype:
    # with this option you do not have to add @flow in files
    onlyFilesWithFlowAnnotation: false

env:
  es6: true
  browser: true
  node: true
  jasmine: true
  jest: true
  jest/globals: true

globals:
  fetch: true
  navigator: true
  __DEV__: true
  XMLHttpRequest: true
  React$Element: true
  Generator: true

parserOptions:
  ecmaVersion: 2017
  sourceType: module
  ecmaFeatures:
    jsx: true

rules:
  prettier/prettier:
    - error
    -
      trailingComma: all
      bracketSpacing: false

  ### Different from airbnb config

  ### Styling ###

  # Prefer new line before return
  # http://eslint.org/docs/rules/newline-before-return
  newline-before-return: error # airbnb default: off

  ### Variables ###

  # Functions and classes can be used before declaration
  # http://eslint.org/docs/rules/no-use-before-define
  no-use-before-define: # airbnb default: ['error', { functions: true, classes: true, variables: true }]
    - error
    -
      functions: false
      classes: false
      variables: true

  ### From error to warning ###
  # was not working when used with flow prop types
  no-unused-vars: warn
  react/no-unused-prop-types: warn

  ### ES6 ###

  ### Best practices ###
  # require or disallow Yoda conditions
  # https://eslint.org/docs/rules/yoda
  yoda: [error, never, { exceptRange: true }] # airbnb default: 'error'

  # add culry braces all the time
  # https://eslint.org/docs/rules/curly
  curly: [error, all] # airbnb default: [error, multi-line]

  ### Import ###

  # Require modules with a single export to use a default export
  # https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/prefer-default-export.md
  import/prefer-default-export: off # airbnb default: 'error'

  # https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/imports-first.md
  import/first: off # airbnb default: ['error', 'absolute-first']

  ### Debugging is allowed but not allowed to commit ###
  no-console: warn # airbnb default: 'error'
  no-debugger: warn # airbnb default: 'error'

  ### React ###
  # do not force jsx use js
  # https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/jsx-filename-extension.md
  react/jsx-filename-extension: off

  # Require stateless functions when not using lifecycle methods, setState or ref
  # https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/prefer-stateless-function.md
  react/prefer-stateless-function: warn # airbnb default: 'error'

  # Enforce a defaultProps definition for every prop that is not a required prop
  # reason: function composition over default props
  # https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/require-default-props.md
  react/require-default-props: off # airbnb default: 'error'

  ### Removed rules
  # no longer defined
  jsx-a11y/href-no-hash: off

  # was complaining about inline snapshots
  no-irregular-whitespace:
  - off