JS Formatter

JS Formatter is a lightweight and customizable JavaScript/TypeScript code formatting library. It uses Babel's powerful parser and traversal tools to format code according to user-defined rules.

Features

• Parse JavaScript and TypeScript code using Babel.
• Apply custom formatting rules, including converting quotes, semicolon usage, and more.
• Flexible options for extensibility and integration into various workflows.
• Command-line interface (CLI) support for ease of use.

Installation

Install the package via npm:

npm install unique-js-formatter

Usage

Programmatic Usage

import formatCode from 'js-formatter';

const inputCode = 'var a = "hello";';
const options = { useSingleQuotes: true };
const formattedCode = formatCode(inputCode, options);

console.log(formattedCode); // Outputs: let a = 'hello';

CLI Usage

You can use the CLI to format files:

npx js-formatter <input-file> [options]

For example:

npx js-formatter example.js --useSingleQuotes

Options

The following options are supported:

• useSingleQuotes: Convert double quotes to single quotes in strings. Default is true.

Development

Project Structure

• src/: Contains the core implementation of the formatter, including parsing, traversal, and code generation.
• tests/: Unit tests for various components of the library.
• script.js: A script to test the Abstract Syntax Tree (AST) generation and traversal.

Running Tests

We use Jest for testing. To run tests, execute:

npm test

Example Test Case

Here is a sample test case:

test('format code', () => {
  const input = 'var a = "hello";';
  const output = "let a = 'hello';";
  expect(formatCode(input, { useSingleQuotes: true })).toBe(output);
});

Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository.
2. Create a feature branch (git checkout -b feature-name).
3. Commit your changes (git commit -m 'Add feature').
4. Push to the branch (git push origin feature-name).
5. Open a pull request.

Acknowledgements

• Babel for providing a robust parser and traversal tools.
• The open-source community for inspiring this project.

Author

Aviral Asthana

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Feel free to raise issues or feature requests on the GitHub repository!