twoslash-eslint

library0.3.8jsnpmunverified

ESLint-backed twoslash runner for annotating code examples with ESLint errors and warnings. Current stable version is 0.3.8, released on a monthly cadence. Key differentiators: integrates ESLint diagnostic results directly into twoslash code blocks, supports TypeScript v6 since v0.3.7, and is part of the twoslash monorepo. Experimental — breaking changes may not follow semver. Ships TypeScript types.

testing devops

npm install twoslash-eslint

github ↗package ↗

INSTALL

IMPORT

SIG · TWOSLASH-ESLINT

twoslash-eslint

testingjavascriptv0.3.8

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.

createTwoslashESLint

✓ import { createTwoslashESLint } from 'twoslash-eslint'

✗ const createTwoslashESLint = require('twoslash-eslint')

ESM-only package; CommonJS require() will fail. Use dynamic import or ESM context.

default

✓ import twoslashESLint from 'twoslash-eslint'

Default export is an alias for createTwoslashESLint. Available since v0.2.0.

TypeScriptESLintRunner

✓ import { TypeScriptESLintRunner } from 'twoslash-eslint'

✗ import { TypeScriptESLintRunner } from 'twoslash'

TypeScriptESLintRunner is a custom runner class exported from twoslash-eslint, not from core twoslash.

Creates an ESLint-backed twoslash runner and applies it to a code example with a custom ESLint rule.

import { createTwoslashESLint } from 'twoslash-eslint' import { createTwoslash } from 'twoslash' const twoslashESLint = createTwoslashESLint({ eslint: { // ESLint options overrideConfig: { rules: { 'no-unused-vars': 'warn' } } } }) const result = createTwoslash({ code: 'let x = 1', defaultCompilerOptions: { strict: true }, customRunners: [twoslashESLint] })

Debug

Known issues

breakingSince v0.3.0, TypeScript ^5.5.0 is explicitly required. Older TypeScript versions are unsupported.

fix

Upgrade TypeScript to >=5.5.0 or stay on v0.2.x if you need older TS support.

affects: <0.3.0

gotchaThe package is experimental and breaking changes may not follow semver.

fix

Pin to a specific version and test upgrades carefully.

affects: >=0.0.0

deprecatedThe `writeGlobalTypes` option was removed in v0.3.5 for Vue integration.

fix

Remove `writeGlobalTypes` from configuration. Use other Vue type handling mechanisms if needed.

affects: >=0.3.5

Errors

Common errors & fixes

ERR_REQUIRE_ESM: require() of ES Module not supported

Using CommonJS require() to import an ESM-only package.

fix

Use dynamic import: const m = await import('twoslash-eslint') or set your project to type: module.

Cannot find module 'twoslash-eslint'

Package not installed or missing from package.json dependencies.

fix

Run npm install twoslash-eslint (peer dep eslint must also be installed).

Upgrade

Version history

0.3.8latest on npm

Audit

Dependencies

eslintrequiredRuntime peer dependency required for ESLint integration

Agent activity

12 hits · last 30 days

node

Resources

githubhttps://github.com/twoslashes/twoslash ↗

packagehttps://www.npmjs.com/package/twoslash-eslint ↗