What "plugins" property in .eslintrc does?

Question

module.exports = {
  root: true,
  parser: '@typescript-eslint/parser',
  plugins: ['@typescript-eslint'],
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
  ],
};

Whenever I add or remove this line: plugins: ['@typescript-eslint'] eslint seems to behave the same. What exactly plugins property does and when using it is required?

Answer 1

This question is pretty straight forward if you think about what a plugin is. The docs don't really do a good job of just out-right saying what an ESLint plugin is, though if you read through the docs (https://eslint.org/docs/user-guide/configuring), then it's pretty trivial to figure out:

ESLint supports the use of third-party plugins

When using rules, environments or configs defined by plugins. Before using the plugin, you have to install it using npm.

So a plugin is a 3rd party module that can define rules, environments, or configs.

So to answer your question:

What exactly plugins property does [sic]

the plugins property tells ESLint what plugins you want to use

and when using it is required? [sic]

when you use something from a plugin, you must first tell ESLint about it with the plugins property.

---

Plugins seem to work anyway when this field is omitted

If you use the extends option with the syntax plugin:<plugin>/<config>, then ESLint will load a specific file from the plugin ahead of time.

Why? Because this allows a plugin to provide a config and reduce the amount of config you need. A plugin's config can provide the plugins option for you, meaning you don't need to do it yourself.