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Discussion on: Make your Angular tests 1000% faster by switching from Karma to Jest

gustavobmichel profile image
Gustavo Borges Michel

Hi Dylan, thank you for this guide. I used a while ago back when we were using Angular 9 and it made such a big difference on execution time for our tests. I have however updated to Angular 10 and updated Jest dependencies alongside and have found an odd behaviour: when you do not provide a stub for a service used in the component, the test hangs indefinitely. I have raised an issue with jest-preset-angular but I was wondering if you have seen this behaviour before:

Thanks in advance.


It turns out it has to do with the Jest 26, and I believe some version after 26.0.1, because when I performed the migration, my package-lock was stamped with 26.0.1 dependant versions and if you install Jest ^26.0.1 now, you end up with 26.4+. I created this other branch with the Jest version on 25 and the problem no longer happens.