michael-s-molina edited a comment on pull request #13149: URL: https://github.com/apache/superset/pull/13149#issuecomment-780741460
@ktmud Setting `testEnv` to `enzyme` enables[ jest-environment-enzyme](https://github.com/enzymejs/enzyme-matchers/tree/master/packages/jest-environment-enzyme#readme) package. This package helps to configure Jest and React integration by setting enzyme adapter and adding React and enzyme to the global scope so we don't need to import them in our tests. As I can tell none of these benefits are being used because our tests are importing React and enzyme in test files and `spec/helpers/shim.ts` is configuring the adapter. Another thing that corroborates this thesis is that our tests successfully execute when we change `testEnv` to `js-dom`. The error happens when `testEnv` equals `enzyme` because `jest-environment-enzyme` depends on js-dom 11.12.0 and `MutationObserver` was introduced in version [13.2.0](https://github.com/jsdom/jsdom/blob/master/Changelog.md). When we changed `testEnv` to `js-dom` the dependency used is 16.4.0 as you can see in the following image: <img width="679" alt="Screen Shot 2021-02-17 at 2 45 00 PM" src="https://user-images.githubusercontent.com/70410625/108246660-762d9600-7130-11eb-88ba-f0e52a8bcffa.png";> ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
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