# eslint-plugin-compat
[](https://github.com/amilajack/eslint-plugin-compat/actions/workflows/test.yml)
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[](http://badge.fury.io/js/eslint-plugin-compat)
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Lint the browser compatibility of your code

## Setup
### 1. Install
```bash
npm install eslint-plugin-compat
```
### 2. Update ESLint Config
#### `.eslintrc.json`
```jsonc
{
"plugins": ["compat"],
"extends": ["plugin:compat/recommended"],
"env": {
"browser": true
}
// ...
}
```
### 3. Configure Target Browsers
Browser targets are configured using [browserslist](https://github.com/browserslist/browserslist). You can configure browser targets in your `package.json`:
#### `package.json`
```jsonc
{
// ...
"browserslist": ["defaults"]
}
```
If no configuration is found, browserslist [defaults to](https://github.com/browserslist/browserslist#queries) `"> 0.5%, last 2 versions, Firefox ESR, not dead"`.
See [browserslist/browserslist](https://github.com/browserslist/browserslist) for more details.
## Adding Polyfills
Add polyfills to the settings section of your eslint config. Append the name of the object and the property if one exists. Here are some examples:
```jsonc
{
// ...
"settings": {
"polyfills": [
// Example of marking entire API and all methods and properties as polyfilled
"Promise",
// Example of marking specific method of an API as polyfilled
"WebAssembly.compile",
// Example of API with no property (i.e. a function)
"fetch",
// Example of instance method, must add `.prototype.`
"Array.prototype.push"
]
}
}
```
## Linting ES APIs (Experimental)
This plugin also supports linting the compatibility of ES APIs in addition to Web APIs. This is an experimental feature and is disabled by default. To enable this feature, add the following to your eslint config:
```jsonc
{
// ...
"settings": {
"lintAllEsApis": true
}
}
```
## Demo
For a minimal demo, see [amilajack/eslint-plugin-compat-demo](https://github.com/amilajack/eslint-plugin-compat-demo)
## Inspiration
Toolchains for native platforms, like iOS and Android, have had API linting from the start. It's about time that the web had similar tooling.
This project was inspired by a two hour conversation I had with someone on the experience of web development and if it is terrible or not. The premise they argued was that `x` browser doesn't support `y` feature while `z` browser does. Eventually, I agreed with him on this and made this plugin to save web developers from having to memorize the browser compatibility of WebAPIs.
## Related
- [ast-metadata-inferer](https://github.com/amilajack/ast-metadata-inferer)
- [compat-db](https://github.com/amilajack/compat-db)
## Contributors
### Code Contributors
This project exists thanks to all the people who contribute. [[Contribute](CONTRIBUTING.md)].
<a href="https://github.com/amilajack/eslint-plugin-compat/graphs/contributors"><img src="https://opencollective.com/eslint-plugin-compat/contributors.svg?width=890&button=false" /></a>
### Financial Contributors
Become a financial contributor and help us sustain our community. [[Contribute](https://opencollective.com/eslint-plugin-compat/contribute)]
#### Individuals
<a href="https://opencollective.com/eslint-plugin-compat"><img src="https://opencollective.com/eslint-plugin-compat/individuals.svg?width=890"></a>
#### Organizations
Support this project with your organization. Your logo will show up here with a link to your website. [[Contribute](https://opencollective.com/eslint-plugin-compat/contribute)]
<a href="https://opencollective.com/eslint-plugin-compat/organization/0/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/0/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/1/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/1/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/2/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/2/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/3/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/3/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/4/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/4/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/5/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/5/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/6/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/6/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/7/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/7/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/8/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/8/avatar.svg"></a>
<a href="https://opencollective.com/eslint-plugin-compat/organization/9/website"><img src="https://opencollective.com/eslint-plugin-compat/organization/9/avatar.svg"></a>