jestjs/jest · error · TypeError

Unable to forward JSDOM console output - neither sendTo nor

Error message

Unable to forward JSDOM console output - neither sendTo nor forwardTo methods are available

What it means

BaseJSDOMEnvironment routes JSDOM's VirtualConsole to Jest's console by calling `forwardTo` (JSDOM 27+) or `sendTo` (JSDOM 26). If the loaded jsdom module's VirtualConsole exposes neither method, the environment cannot forward browser console output and throws at index.ts:68 rather than silently dropping logs.

Source

Thrown at packages/jest-environment-jsdom-abstract/src/index.ts:68

    const {JSDOM, ResourceLoader, VirtualConsole} = jsdomModule;

    const virtualConsole = new VirtualConsole();

    if (
      'forwardTo' in virtualConsole &&
      typeof virtualConsole.forwardTo === 'function'
    ) {
      // JSDOM 27+ uses `forwardTo`
      virtualConsole.forwardTo(context.console);
    } else if (
      'sendTo' in virtualConsole &&
      typeof virtualConsole.sendTo === 'function'
    ) {
      // JSDOM 26 uses `sendTo`
      virtualConsole.sendTo(context.console, {omitJSDOMErrors: true});
    } else {
      // Fallback for unexpected API changes
      throw new TypeError(
        'Unable to forward JSDOM console output - neither sendTo nor forwardTo methods are available',
      );
    }

    virtualConsole.on('jsdomError', error => {
      context.console.error(error);
    });

    this.dom = new JSDOM(
      typeof projectConfig.testEnvironmentOptions.html === 'string'
        ? projectConfig.testEnvironmentOptions.html
        : '<!DOCTYPE html>',
      {
        pretendToBeVisual: true,
        resources:
          typeof projectConfig.testEnvironmentOptions.userAgent === 'string'
            ? new ResourceLoader({
                userAgent: projectConfig.testEnvironmentOptions.userAgent,

View on GitHub (pinned to f49721c78e)

Solutions

Upgrade `jest-environment-jsdom` to a version matching your jsdom major (jsdom 27 needs the forwardTo-aware adapter).
Pin `jsdom` to a supported major (26 or 27) in resolutions/overrides.
If you ship a custom jsdom shim, implement `forwardTo(console)` or `sendTo(console)` on its VirtualConsole.
Run `npm ls jsdom` to find the conflicting copy and dedupe.

Example fix

// before (package.json)
"devDependencies": {
  "jest-environment-jsdom": "^30",
  "jsdom": "^21"
}

// after
"devDependencies": {
  "jest-environment-jsdom": "^30",
  "jsdom": "^27"
}

Defensive patterns

Strategy: validation

Validate before calling

const jsdom = require('jsdom');
const vc = new jsdom.VirtualConsole();
if (typeof vc.forwardTo !== 'function' && typeof vc.sendTo !== 'function') {
  throw new Error(`jsdom ${require('jsdom/package.json').version} is unsupported by this adapter`);
}

Type guard

const supportsForwarding = (vc: any): boolean => typeof vc.forwardTo === 'function' || typeof vc.sendTo === 'function';

Prevention

Pin jsdom to a major supported by jest-environment-jsdom.
Run `npm ls jsdom` after dependency changes.
Keep jest-environment-jsdom and jsdom versions in lockstep.

When it happens

Trigger: Loading a jsdom version older than 26 (no sendTo/forwardTo), a fork/stub of jsdom, or a future jsdom that renames the API again. Triggered at environment construction time, before any test runs.

Common situations: Pinning a very old `jsdom` in package.json while using a newer `jest-environment-jsdom`; a yarn/npm resolution that pulls a different jsdom major; a custom environment that injects a mock jsdom module; jsdom releases a new major and the abstract adapter has not been updated yet.

Related errors

AI-assisted analysis of jestjs/jest@f49721c78e (2026-08-03). Data as JSON: /data/errors/4619b9b480914236.json. Report an issue: GitHub.