Registry / testing / eslint-plugin-escompat

eslint-plugin-escompat

library3.11.4jsnpmunverified

ESLint plugin (v3.11.4) that reports errors for JavaScript/TypeScript syntax which, if left untranspiled, will not work in target browsers, as defined by a Browserslist config. Unlike eslint-plugin-compat (which checks for missing polyfills), this focuses on native syntax incompatibilities. It ships with recommended configs for browser code and separate TypeScript configs per ECMAScript target year. Integrates with both legacy .eslintrc and flat eslint.config.js formats. Actively maintained with multiple releases per year since initial release.

testing

npm install eslint-plugin-escompat

github ↗package ↗

INSTALL

IMPORT

SIG · ESLINT-PLUGIN-ESCO

eslint-plugin-escompat

testingjavascriptv3.11.4

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import escompat from 'eslint-plugin-escompat'

✗ const escompat = require('eslint-plugin-escompat')

ESM import used in flat config; CommonJS require works with .eslintrc in ESLint <9.

escompat.configs['flat/recommended']

✓ import escompat from 'eslint-plugin-escompat'; export default [{ ... }, escompat.configs['flat/recommended']]

✗ using escompat.configs['flat/recommended'] without spreading or in .eslintrc

Flat config is an object, not an array; extend in export default array.

escompat.configs['flat/typescript-2020']

✓ import escompat from 'eslint-plugin-escompat'; export default [{ ... }, ...escompat.configs['flat/typescript-2020']]

✗ escompat.configs['flat/typescript-2020'] without spread operator

TypeScript flat configs are arrays; must spread them into config array.

Flat config example enabling two escompat rules with browser globals.

// eslint.config.js import globals from 'globals'; import escompat from 'eslint-plugin-escompat'; export default [ { plugins: { escompat }, languageOptions: { globals: globals.browser }, rules: { 'escompat/no-async-generator': 'error', 'escompat/no-numeric-separators': 'error', } } ];

Debug

Known issues

breakingv3.11.2 fixed a breaking change where Browserslist API broke `this` context in custom browserslist configs.

fix

Update to v3.11.2 or later.

affects: 3.11.0, 3.11.1

deprecated.eslintrc (non-flat) config style is deprecated in ESLint 9; only flat config is recommended going forward.

fix

Migrate to flat config (eslint.config.js) using eslint-plugin-escompat's flat configs.

affects: >=3.11.0

gotchaRules are only effective if you have a browserslist configured in package.json or .browserslistrc. Without one, all rules are disabled.

fix

Add a browserslist to your project (e.g., 'last 1 version') or define it in a config file.

affects: >=3.0.0

gotchaThe 'recommended' config only enables rules that cover syntax not yet widely supported; it may not catch all potential incompatibilities. Always pair with eslint-plugin-compat for polyfill checks.

fix

Use both eslint-plugin-escompat and eslint-plugin-compat for full coverage.

affects: >=3.0.0

Errors

Common errors & fixes

Error: Failed to load plugin 'escompat' declared in '.eslintrc'

Missing eslint-plugin-escompat package or incorrect plugin name in config.

fix

Run 'npm install --save-dev eslint-plugin-escompat' and ensure the plugin is listed as 'escompat' in plugins.

Configuration for rule 'escompat/no-async-generator' is invalid

Rule is not recognized; either the plugin is not loaded, or the rule name is misspelled.

fix

Check that the plugin is correctly loaded and the rule name matches exactly (e.g., 'no-async-generator', not 'no-async-generator-something').

Definition for rule 'escompat/no-*' was not found

The rule does not exist in the plugin version installed.

fix

Update to latest version: 'npm update eslint-plugin-escompat' and verify available rules in documentation.

TypeError: Cannot read properties of undefined (reading 'includes')

Possibly related to a missing or malformed browserslist config causing rule parsing to fail.

fix

Ensure browserlist is defined properly in package.json or .browserslistrc (e.g., 'last 1 version').

Upgrade

Version history

3.11.4latest on npm

Audit

Dependencies

eslintrequiredpeer dependency; plugin requires ESLint >=5.14.1

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/keithamus/eslint-plugin-escompat ↗

packagehttps://www.npmjs.com/package/eslint-plugin-escompat ↗