biome-plugin-arrow-body-style

A Biome linter plugin that enforces braces around arrow function bodies, requiring the use of block statements instead of expression bodies for consistency and clarity.

Installation

Install the plugin as a dev dependency:

npm install --save-dev biome-plugin-arrow-body-style

or with your preferred package manager:

yarn add -D biome-plugin-arrow-body-style
pnpm add -D biome-plugin-arrow-body-style
bun add -D biome-plugin-arrow-body-style

Usage

Add the plugin to your Biome configuration file (biome.json or biome.jsonc):

{
  "$schema": "./node_modules/@biomejs/biome/configuration_schema.json",
  "plugins": [
    "node_modules/biome-plugin-arrow-body-style/arrow-body-style.grit"
  ]
}

To ignore it

// biome-ignore lint/plugin/arrow-body-style: <reason>
const getValue = () => 42;

The plugin will now check your code and report errors when it detects arrow functions without braces around their bodies.

What it catches

The plugin enforces braces around arrow function bodies:

// ❌ Error - expression body without braces
const getValue = () => 42;
const add = (a, b) => a + b;

// ✅ Correct - block statement with braces
const getValue = () => {
  return 42;
};
const add = (a, b) => {
  return a + b;
};

Why enforce arrow function braces?

Requiring braces around arrow function bodies provides several benefits:

• Consistency: Maintains a uniform code style across your codebase
• Clarity: Makes function intent and return statements explicit
• Maintainability: Easier to add logic without accidentally changing return behavior
• Readability: Clearer distinction between simple expressions and actual function bodies

Contributing

Contributions are welcome! Here's how to get started:

Setup

Clone the repository:

git clone https://github.com/jeremytenjo/biome-plugin-arrow-body-style.git
cd biome-plugin-arrow-body-style

Install dependencies:

npm install

Development

The plugin is defined in arrow-body-style.grit using the Grit pattern language.

Testing

Run the test suite:

npm test

Tests are located in the test directory and use Vitest. Test fixtures can be found in test/fixtures.

Publishing

To publish a new version of the plugin:

1. Update the version in package.json.
2. Publish to npm:

   npm publish

3. Tag the release in GitHub creating a Release with the changes.

License

MIT © Jeremy Tenjo