chore: change test environment to jsdom

[michael-s-molina]

SUMMARY

Change test environment to jsdom (default when installed) so we can use react-testing-library functions that listen for DOM mutations like findBy.

Test environment with enzyme option was causing TypeError: MutationObserver is not a constructor

@ktmud @rusackas @geido

Add to #13079

TEST PLAN

1 - Execute all jest tests
2 - All tests should pass

ADDITIONAL INFORMATION

• Has associated issue:
• Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

[geido]

LGTM!

[rusackas]

LGTM!

[ktmud]

Do you know what's the benefit of setting testEnv to enzyme and why changing it doesn't break existing enzyme tests?

[michael-s-molina]

@ktmud Setting testEnv to enzyme enables jest-environment-enzyme 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. When we changed testEnv to js-dom the dependency used is 16.4.0 as you can see in the following image:

[ktmud]

Thanks for the clarification!