Question 1

How do I set up eslint-plugin-compat for Internet Explorer support?

Accepted Answer

Add IE versions to your Browserslist configuration in package.json, e.g., 'IE 11', and configure polyfills for unsupported APIs like fetch in the ESLint settings to avoid warnings.

Question 2

eslint-plugin-compat vs Babel preset-env for polyfilling?

Accepted Answer

eslint-plugin-compat focuses on linting to identify compatibility gaps, while Babel preset-env handles transpilation and polyfilling. They work best together—the plugin warns about issues, and Babel can fix them.

Question 3

Does eslint-plugin-compat work with TypeScript projects?

Accepted Answer

Yes, but you need to integrate it with an ESLint setup that supports TypeScript parsing. It lints the JavaScript output, so ensure your TypeScript compiler targets are aligned with Browserslist.

Question 4

How to ignore false positives for certain APIs?

Accepted Answer

Mark APIs as polyfilled in the settings, or use ESLint disable comments. However, there's no built-in ignore feature for non-polyfilled APIs, requiring workarounds.

Question 5

Can eslint-plugin-compat check CSS compatibility?

Accepted Answer

No, it only lints JavaScript APIs and ES features. For CSS, use tools like stylelint or autoprefixer, as mentioned in the inspiration for web development tooling.

Question 6

What browsers does eslint-plugin-compat target by default?

Accepted Answer

If no Browserslist config is found, it defaults to '> 0.5%, last 2 versions, Firefox ESR, not dead', which is broad and might not match specific project needs without customization.

Compat

What is Compat?

Overview

Use Cases

Best For

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions