.eslintrc.yml

---
env:
  browser: true
  es2020: true
  webextensions: true
extends:
  # https://github.com/airbnb/javascript/tree/master/packages/eslint-config-airbnb-base/rules
  - airbnb-base
  - plugin:import/typescript
  - plugin:@typescript-eslint/eslint-recommended
  - plugin:@typescript-eslint/recommended
parser: "@typescript-eslint/parser"
plugins:
  - "@typescript-eslint"
parserOptions:
  ecmaVersion: 11
  project:
    - './tsconfig.json'
  sourceType: module
settings:
  # https://newbedev.com/using-eslint-with-typescript-unable-to-resolve-path-to-module
  # https://stackoverflow.com/a/63451047/2625807
  # https://stackoverflow.com/a/61065416/2625807
  import/resolver:
    typescript: {}
rules:
  # might be worth bringing no-console back or stripping as part of
  # the build once this is more mature - right now it's helpful in
  # development
  no-console: "off"
  # Not sure of other easy UI available in an omnibox action
  no-alert: "off"
  # They're not wrong - I suspect I'm not using classes in a canonical
  # way - just not ready to take this on yet.
  class-methods-use-this:
    - "off"
  #
  # Dangling commas on a function call/declaration just seems *wrong*,
  # regardless of what the geniuses at AirBNB think.
  #
  comma-dangle:
    - error
    - arrays: always-multiline
      objects: always-multiline
      imports: always-multiline
      exports: always-multiline
      functions: never
  dot-notation: "off"
  "@typescript-eslint/dot-notation": warn
  import/prefer-default-export:
    # I build files incrementally, intending for more than one
    # function to be within; having this tell me to default export the
    # first function isn't helpful.
    - "off"
  import/extensions:
    # doesn't seem compatible with esm support in node and typescript,
    # where I import a .js filename that is satisfied by the
    # .ts filename in my source
    #
    # https://stackoverflow.com/a/60675852/2625807
    - "off"
  # Disallow default exports, as they seem to stochastically cause
  # babel+jest failures as of 2022-11
  import/no-default-export:
    - error
  import/no-extraneous-dependencies:
    - error
    # Avoids this error:
    #  'jest-chrome' should be listed in the project's dependencies, not devDependencies. []
    - devDependencies:
        - "**/*.test.tsx"
        - "**/*.test.ts"
        - "**/*.spec.ts"
        - "**/*.spec.tsx"
        - "jest.setup.js"
        - "webpack.config.js"
  # I don't know whether 'use strict' is the default in Chrome
  # extensions, so let's assume not.
  strict:
    - error
    - safe
  # for of rules are not relevant when we are only extending modern browsers
  #
  # https://github.com/airbnb/javascript/issues/1271#issuecomment-548688952
  no-restricted-syntax:
    - error
    - 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: 'ForOfStatement'
    #   message: 'iterators/generators require regenerator-runtime, which is too heavyweight for this guide to allow \
    #    them. Separately, loops should be avoided in favor of array iterations.'
    - 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.'
  no-param-reassign:
    - error
    # this overrides the airbnb default.  callbacks modifying DOM
    # elements seem a reasonable thing to do, and the default of
    # 'props: true' would make that difficult, as the increasingly
    # ridiculous list of ways to fool the linter on this stackoverflow
    # page suggests:
    #
    # https://stackoverflow.com/questions/35637770/how-to-avoid-no-param-reassign-when-setting-a-property-on-a-dom-object
    - props: false
  # https://github.com/typescript-eslint/typescript-eslint/issues/2540#issuecomment-692510509
  no-use-before-define: "off"
  # I couldn't figure out how to translate this; do I even have regexp literals configued to be used?
  #   new RegExp('/\\d+/(\\d+)/(\\d+)[/f]?');
  prefer-regex-literals: "off"
  "@typescript-eslint/no-use-before-define": warn
# arrow-body-style
# https://github.com/airbnb/javascript/blob/35914b14025cd52f53cd2ae2f353cdc7384087c0/packages/eslint-config-airbnb-base/rules/es6.js#L15-L20