[Feature]: Support Jest 30

[swierzbicki]

🚀 Feature Proposal

There is new, quicker version of Jest: https://github.com/jestjs/jest/releases/tag/v30.0.0

1. Are there any plans to add support for Jest 30?
2. How much work will this require?

Motivation

Improved performance: https://jestjs.io/blog/2025/06/04/jest-30#performance--memory-improvements

[Julien-Marcou]

I locally tried jest 30 (force install) on a fairly substantial angular repository with jest-preset-angular, and it went pretty well, though you should expect some breaking changes that will require some fixes on your side.

On some of our tests, we are using jest.spyOn(window, 'location', ...) and Object.defineProperty(window, 'location', ...), but this now results in the following error Property location is not declared configurable.

Also the coverage seems to be calculated differently now, resulting in a lower coverage (because it's more strict I believe), which means some of our coverage thresholds were not longer met and needed adjustments.

Regarding the performance, I didn't see a substantial difference between jest 29 & 30.

[talamaska]

The big fix here is that they are not using inflight anymore which was in some old version of glob and also deprecations of node 14, which is ok for angular 19, which was causing memory leaks. And I encountered issues related to that, like jest reporting different coverage numbers because it didn't had the memory, because of the leaks to run all the tests. I guess it depends on what CI/CD you are doing this. My issue is that this plugin already updated to angular 20. But I don't see a reason not to use jest 30 with angular 19 and avoid having this memory leak. I know I shouldn't have any issues upgrading to 20 and probably it will be flawless, because we already removed all the deprecated ngIf and ngFors. The only blocker for me to use the new jest in my project is this package.

[it11ah1]

I'm a bit confused about the current progress of this issue. I would really like to take advantage of the improvements introduced in Jest 30 within my Angular project. One particularly critical point is that it's still relying on jsdom@20.0.3, which dates back to 2022.

[devfservant]

Actually you can already use other jsdom versions: https://thymikee.github.io/jest-preset-angular/docs/guides/jsdom-environment
Personally I use jsdom v26 with that