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Error after upgrading to Node 16.6.0 when using ES modules

See original GitHub issue

🐛 Bug Report

Calling jest gives the error:

TypeError: String.prototype.startsWith called on null or undefined
    at startsWith (<anonymous>)
    at node:internal/errors:811:19
    at Array.filter (<anonymous>)
    at node:internal/errors:809:16
    at prepareStackTrace (node:internal/errors:96:12)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1138:38)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Module.require (node:internal/modules/cjs/loader:1005:19)
    at require (node:internal/modules/cjs/helpers:94:18)

To Reproduce

Steps to reproduce the behavior:

Install Node.js 16.6.0 (versions 16.5.0– are not affected)
Create a project using ES modules ("type": "module" in package.json) and install jest ^27.0.6
Create a jest.config.js config file with a default export.
Run jest (npx jest, yarn jest, etc.)

Expected behavior

Jest runs without errors.

Link to repl or repo (highly encouraged)

https://github.com/adalinesimonian/node-jest-16.6-error-repro

envinfo

  System:
    OS: Linux 5.4 Fedora Remix for WSL 34
    CPU: (32) x64 AMD Ryzen 9 3950X 16-Core Processor
  Binaries:
    Node: 16.6.0 - ~/.volta/tools/image/node/16.6.0/bin/node
    Yarn: 3.0.0 - ~/.volta/tools/image/yarn/1.22.11/bin/yarn
    npm: 7.20.3 - ~/.volta/tools/image/npm/7.20.3/bin/npm
  npmPackages:
    jest: ^27.0.6 => 27.0.6

Issue Analytics

State:
Created 2 years ago
Reactions:8
Comments:10 (3 by maintainers)

Top GitHub Comments

4reactions

adalinesimoniancommented, Aug 4, 2021

Verified issue is fixed with Node.js 16.6.1. Closing issue!

1reaction

sigveiocommented, Jul 31, 2021

Thanks for posting clear steps to reproduce and a repo link, @adalinesimonian

I just tested and can confirm what you are seeing.

The “ESM mode” of Jest (activated when you for example set "type": "module" in package.json) is still very much incomplete/experimental and has a lot of known and unknown issues. You can read more about it on this page, and in the tracking issue here.

If you’d have the time to dig deeper and try to find out what might be causing this particular error, I’m sure the help would be appreciated =)