https://github.com/amilajack/babel-plugin-fail-explicit

A babel plugin that prevents coercion and silent failure in JavaScript
https://github.com/amilajack/babel-plugin-fail-explicit

babel coercion explicit fail failure plugin safe silent

Last synced: about 2 months ago
JSON representation

A babel plugin that prevents coercion and silent failure in JavaScript

• Host: GitHub
• URL: https://github.com/amilajack/babel-plugin-fail-explicit
• Owner: amilajack
• License: mit
• Created: 2017-03-19T05:12:05.000Z (almost 8 years ago)
• Default Branch: master
• Last Pushed: 2022-03-26T14:13:01.000Z (over 2 years ago)
• Last Synced: 2024-10-17T06:54:34.285Z (2 months ago)
• Topics: babel, coercion, explicit, fail, failure, plugin, safe, silent
• Language: JavaScript
• Homepage:
• Size: 852 KB
• Stars: 7
• Watchers: 3
• Forks: 3
• Open Issues: 17
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE

Awesome Lists containing this project

README

        
babel-plugin-fail-explicit

==========================

[![Build Status](https://travis-ci.org/amilajack/babel-plugin-fail-explicit.svg?branch=master&maxAge=2592)](https://travis-ci.org/amilajack/babel-plugin-fail-explicit)

[![NPM version](https://badge.fury.io/js/babel-plugin-fail-explicit.svg?maxAge=2592)](http://badge.fury.io/js/babel-plugin-fail-explicit)

[![Dependency Status](https://img.shields.io/david/amilajack/babel-plugin-fail-explicit.svg?maxAge=2592)](https://david-dm.org/amilajack/babel-plugin-fail-explicit)

[![npm](https://img.shields.io/npm/dm/babel-plugin-fail-explicit.svg?maxAge=2592)](https://npm-stat.com/charts.html?package=babel-plugin-fail-explicit)

**A babel plugin that prevents coercion and silent failure in JavaScript**

![demo](https://raw.githubusercontent.com/amilajack/babel-plugin-fail-explicit-demo/7ed9a29ec61d505f2b3ce6be18145c74eb3bc5f5/demo.gif)

## Roadmap

- [x] Fail on unsafe coercion

- [x] Fail on unsafe property access

- [x] Do not fail inside conditional expressions or default statements (`||`), on by default

- [ ] Allow unsafe access in if statement by default

- [ ] Allow for configuration of strictness

## Installation

```bash

npm install --save-dev babel-plugin-fail-explicit

```

## Setup

```json

// .babelrc

{

  "plugins": [

    "fail-explicit"

  ]

}

```

### Demo:

To experiment with `babel-plugin-fail-explicit`, see [this demo repo](https://github.com/amilajack/babel-plugin-fail-explicit-demo)

### Examples

```js

// ------------------------------------------------

// Coercion safeguard

// ------------------------------------------------

[] + {}

// TypeError: 'Unexpected coercion of type "Array" and

// type "Object" using "+" operator'

NaN + undefined

// TypeError: Unexpected coercion of type "NaN" and type

// "undefined" using "+" operator

1 + 'some'

// '1some'

// ------------------------------------------------

// Safe Comparison

// ------------------------------------------------

new String('12') > 12

// TypeError: Unexpected comparison of type "String" and type

// "number" using ">" operator

null > undefined

// TypeError: Unexpected comparison of type "null" and type

// "undefined" using ">" operator

// ------------------------------------------------

// Usage for better undefined propagation errors

// ------------------------------------------------

const obj = {

  foo: {

    bar: {}

  }

}

obj.foo.bar.baz;

// TypeError: Property "baz" does not exist in "Object.foo.bar"

// ------------------------------------------------

// Usage as out of bounds check

// ------------------------------------------------

const some = new Array(3)

some[10]

// TypeError: '"Array[10]" is out of bounds'

const bar = []

some[100]

// TypeError: '"Array[100]" is out of bounds'

// TypeError: '"woo[1]" is out of bounds'

const obj = {

  woo: ['']

}

obj.woo[1]

// TypeError: '"woo[1]" is out of bounds'

```