delete-js-comments

A lightweight, fast, and secure package to remove all types of comments from JavaScript code

Features

• Fast & Efficient - Optimized performance with array-based string building
• Secure - Input validation and DoS protection built-in
• Zero Dependencies - No external packages required
• Simple API - Just one function, easy to use
• ES6 Modules - Modern JavaScript support
• Safe - Preserves comments inside string literals

Removes All Comment Types

• Single-line comments (//)
• Multi-line comments (/* */)
• JSDoc comments (/** */)
• Inline comments

Installation

npm install delete-js-comments

Or install globally to use as a CLI tool:

npm install -g delete-js-comments

Quick Start

As a Module

import deleteComments from 'delete-js-comments';

const code = `
// This is a comment
const x = 5; // inline comment

/* Multi-line
   comment */
function hello() {
  return "world";
}
`;

const cleanCode = deleteComments(code);
console.log(cleanCode);

As a CLI Tool

Recommended: Use npx (no installation required)

# Output to stdout
npx delete-js-comments input.js

# Save to output file
npx delete-js-comments input.js output.js

# Overwrite the input file
npx delete-js-comments input.js --overwrite

# Use with pipes
cat input.js | npx delete-js-comments > output.js

Or install globally:

npm install -g delete-js-comments

# Then use directly
delete-js-comments input.js --overwrite
delete-js-comments input.js output.js

CLI Usage

Installation Options

# Option 1: Use npx (no installation)
npx delete-js-comments file.js

# Option 2: Install globally
npm install -g delete-js-comments
delete-js-comments file.js

# Option 3: Install locally in project
npm install delete-js-comments
npx delete-js-comments file.js

Basic Commands

# Process a single file (output to stdout)
delete-js-comments src/app.js

# Save to a specific output file
delete-js-comments src/app.js dist/app.js

# Overwrite the original file
delete-js-comments src/app.js --overwrite

# Process all JavaScript files in a directory recursively
delete-js-comments src/

# Process a directory and save to output directory
delete-js-comments src/ dist/

Security Features

The CLI tool includes comprehensive security features:

• Path Traversal Protection - Blocks attempts to access files outside the current directory
• File Type Validation - Only processes .js, .jsx, .mjs, .cjs files
• Sensitive File Blocking - Prevents modification of:
  • Configuration files (package.json, .env, etc.)
  • Build/dependency files (node_modules, dist, etc.)
  • Version control files (.git, .gitignore)
• Size Limits - Files are limited to 10MB to prevent DoS attacks

API Reference

deleteComments(code)

Removes all types of comments from JavaScript code while preserving comments in string literals.

Parameters

• code (string): The JavaScript code to process

Returns

• (string): The code with all comments removed

Throws

• TypeError: If the input is not a string
• Error: If the input exceeds the 10MB size limit

Example

import deleteComments from 'delete-js-comments';

const jsCode = `
// This will be removed
const message = "// This will be preserved";

/**
 * This JSDoc will be removed
 */
function greet() {
  return message; /* This comment will be removed */
}
`;

const clean = deleteComments(jsCode);
console.log(clean);

Output:

const message = "// This will be preserved";

function greet() {
  return message; 
}

Security

This package includes several security features:

Input Validation

• Type checking ensures only strings are processed
• Size limit of 10MB per input to prevent DoS attacks

Memory Safety

• Uses array-based string building to prevent memory exhaustion
• Efficient algorithms to handle large files

Safe Processing

• Preserves string literals to avoid breaking code
• Handles edge cases safely

For more details, see SECURITY.md.

How It Works

The package uses a state machine approach to parse JavaScript code:

1. Tracks whether we're inside a string literal
2. Detects comment start sequences (// or /*)
3. Removes comments while preserving code structure
4. Handles escape sequences in strings correctly
5. Maintains line breaks for better code structure

Limitations

• Only processes JavaScript/JSX files (not TypeScript)
• Does not handle template literals with nested comments
• Assumes valid JavaScript syntax (won't parse broken code)

Contributing

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

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

MIT © 2025

See LICENSE for more information.

Repository

https://github.com/benshabbat/deleteComments

Support

• Report issues: https://github.com/benshabbat/deleteComments/issues
• Star the project if you find it useful!

Related Packages

• strip-comments
• decomment

Changelog

See CHANGELOG.md for version history.