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[Bug]: Cannot use with lit-element due to ESM errors, even with transformIgnorePatterns

See original GitHub issue

Version

27.0.6

Steps to reproduce

Clone my minimal reproducible repo: https://github.com/cdrini/lit-jest-babel-test
Run npm install
Run npx jest

Expected behavior

I expect to see the tests run

Actual behavior

The test is not run with this error:

    Details:

    C:\...\lit-jest-babel-test\node_modules\lit-element\lit-element.js:57
    import { render } from 'lit-html/lib/shady-render.js';
    ^^^^^^

    SyntaxError: Cannot use import statement outside a module

Despite the fact that this is file should be babel-ed by my jest.config.js

Additional context

No response

Environment

System:
    OS: Windows 10 10.0.19042
    CPU: (8) x64 Intel(R) Core(TM) i5-8250U CPU @ 1.60GHz
  Binaries:
    Node: 14.16.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.17.3 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 6.14.7 - C:\Program Files\nodejs\npm.CMD
  npmPackages:
    jest: ^27.0.6 => 27.0.6

Issue Analytics

State:
Created 2 years ago
Reactions:2
Comments:10 (1 by maintainers)

Top GitHub Comments

3reactions

cdrinicommented, Aug 25, 2021

Gaaaah, I finally figured it out! Huge thanks to @austinkelleher and https://github.com/facebook/jest/issues/6229#issuecomment-403539460 .

The issue was my .babelrc needed to be renamed to babel.config.js 😖 . Is there any way we could maybe surface this as a warning on https://jestjs.io/docs/ecmascript-modules ? Cause otherwise the fix was really simple and logical; just add lit-element/lit-html to the list of ignored transforms.

0reactions

github-actions[bot]commented, May 26, 2022

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs. Please note this issue tracker is not a help forum. We recommend using StackOverflow or our discord channel for questions.

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