Did Firebase Cloud Functions ESLint change recently?

Question

I created a cloud function project with firebase a few months ago, and used linting.

I recently created a new cloud function project with linting, and now the linter is complaining about random rules I never set. I don't remember it enforcing nearly the amount of style rules a few months ago.

Things like:

This line has a length of 95. Maximum allowed is 80
Missing JSDoc comment
Missing Trailing comma
expected indentation of 2 spaces but found 4
Strings must use singlequote

It's also not letting me use async/await.

I found out I can individually set these rules in my .eslintrc.js file, but that's annoying and I don't want to do that. By default, why aren't these rules disabled? I just want basic rules that make sure my code won't fail when run, not random style preferences like single/double quotes and max line length.

Is there any way to use just basic linting functionality with firebase functions?

Answer 1

I ran into the same issue as you. The new, more strict linting rules seem to come from the fact that Firebase functions use the "google" eslint base configuration plugin by default now. Read more about configuring ESLint plugins in the docs. My older Firebase functions were using tslint without issue.

Here's what my .eslintrc.js file looked like while I was getting style errors from eslint:

module.exports = {
    env: {
        es6: true,
        node: true,
    },
    extends: [
        'eslint:recommended',
        'plugin:import/errors',
        'plugin:import/warnings',
        'plugin:import/typescript',
        'google',
    ],
    parser: '@typescript-eslint/parser',
    parserOptions: {
        project: ['tsconfig.json', 'tsconfig.dev.json'],
        sourceType: 'module',
    },
    ignorePatterns: [
        '/lib/**/*', // Ignore built files.
    ],
    plugins: ['@typescript-eslint', 'import'],
    rules: {
        quotes: ['error', 'double'],
    },
};

I deleted 'google' from the extends property, which seemed to resolve almost all of the style linting issues.

Now it looks like this:

module.exports = {
    env: {
        es6: true,
        node: true,
    },
    extends: [
        'eslint:recommended',
        'plugin:import/errors',
        'plugin:import/warnings',
        'plugin:import/typescript',
    ],
    parser: '@typescript-eslint/parser',
    parserOptions: {
        project: ['tsconfig.json', 'tsconfig.dev.json'],
        sourceType: 'module',
    },
    ignorePatterns: [
        '/lib/**/*', // Ignore built files.
    ],
    plugins: ['@typescript-eslint', 'import'],
    rules: {
        quotes: ['error', 'double'],
    },
};

Answer 2

You can get rid of the google extends value but I would suggest keeping it and just turning off the rules that bother you the most, which for me is indentation and max length (of lines):

module.exports = {
  root: true,
  env: {
    es6: true,
    node: true,
  },
  extends: [
    "eslint:recommended",
    "google",
  ],
  rules: {
    "quotes": ["error", "double"],
    "indent": ["off"],
    "max-len": ["off"],
  },
};

For anyone who is confused by this, there is a lint config file in the Cloud Functions folder that you can edit. As of this answer, that file is named .eslintrc.js.