eslint-plugin-snakify v1.0.0

eslint-plugin-snakify

An ESLint plugin that enforces snake_case naming convention for variables and functions. This plugin helps maintain consistent naming conventions in your JavaScript/TypeScript codebase by automatically detecting and fixing camelCase or PascalCase identifiers to snake_case.

Features

• 🔍 Detects variables and functions not following snake_case convention
• 🛠 Provides automatic fixes to convert identifiers to snake_case
• ⚙️ Highly configurable with options to:
  • Whitelist specific identifiers
  • Filter specific AST node types
  • Ignore object properties
  • Ignore destructured variables
  • Use custom conversion functions

Installation

You'll first need to install ESLint:

# npm
npm install eslint --save-dev

# pnpm
pnpm add -D eslint

# bun
bun add -D eslint

Next, install eslint-plugin-snakify:

# npm
npm install eslint-plugin-snakify --save-dev

# pnpm
pnpm add -D eslint-plugin-snakify

# bun
bun add -D eslint-plugin-snakify

Usage

Add snakify to the plugins section of your ESLint configuration. You can do this in either your .eslintrc.json file or in the ESLint configuration within your package.json.

ESLint Flat Config (recommended for ESLint 9+)

// eslint.config.js
import snakify from 'eslint-plugin-snakify';

export default [
  {
    plugins: {
      'snakify': snakify,
    },
    rules: {
      'snakify/snakify': ['error', {
        // options (all optional)
        whitelist: [], // identifiers to ignore
        filter: ['ClassDeclaration', 'NewExpression'], // AST node types to ignore
        ignoreProperties: false, // whether to ignore object property names
        ignoreDestructuring: false, // whether to ignore destructured variable names
      }],
    },
  },
];

Traditional ESLint Config

{
  "plugins": ["snakify"],
  "rules": {
    "snakify/snakify": ["error", {
      "whitelist": [],
      "filter": ["ClassDeclaration", "NewExpression"],
      "ignoreProperties": false,
      "ignoreDestructuring": false
    }]
  }
}

Rule Options

The rule accepts an options object with the following properties:

• whitelist: Array of identifiers to ignore (default: [])
• filter: Array of AST node types to ignore (default: ["ClassDeclaration", "NewExpression"])
• ignoreProperties: Whether to ignore object property keys (default: false)
• ignoreDestructuring: Whether to ignore destructured identifiers (default: false)
• customConverter: Custom function to convert identifiers to snake_case (optional)

Examples

Valid Code Examples

// Valid snake_case
const my_variable = 5;
function my_function() {}

// Class names are ignored by default
class MyClass {}

// With ignoreProperties: true
const obj = { myProperty: 5 };

// With ignoreDestructuring: true
const { myProp } = obj;

// With whitelist: ["mySpecialCase"]
const mySpecialCase = 5;

Invalid Code Examples

// ❌ Invalid
const myVariable = 5;
// ✅ Valid after fix
const my_variable = 5;

// ❌ Invalid
const MyVariable = 5;
// ✅ Valid after fix
const my_variable = 5;

// ❌ Invalid
const myComplexVariableName = 5;
// ✅ Valid after fix
const my_complex_variable_name = 5;

Using with TypeScript

This plugin works seamlessly with TypeScript. Just make sure you have @typescript-eslint/parser configured:

// eslint.config.js
import snakify from 'eslint-plugin-snakify';
import typescript from '@typescript-eslint/parser';

export default [
  {
    languageOptions: {
      parser: typescript,
    },
    plugins: {
      'snakify': snakify,
    },
    rules: {
      'snakify/snakify': 'error',
    },
  },
];

Development

# Install dependencies
pnpm install

# Run tests
pnpm test

# Run tests in watch mode
pnpm test:watch

# Run tests with coverage
pnpm test:coverage

# Build the plugin
pnpm build

# Lint the code
pnpm lint

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT