Karma Test Runner Migration

[bryankenneally]

What should we do?

The modeler tests are currently run using Karma as the test runner. However Karma is deprecated and no longer being updated. We should look at utilizing another test engine (e.g. Jest or Vitest) and migrating the tests from Karma to this new test engine.

Why should we do it?

Karma is deprecated and no longer being updated

[bryankenneally]

FYI @finos/fluxnova-maintainers

We are actively pursuing migrating the ~1700 tests from Karma to Jest, and from Enzyme to React Testing Library using a combination of codemods and GenAI tooling.

This will facilitate our upgrade path from React 16 to v18 and beyond.

Here are some resources we have used to help inform our approach to the migration:

• https://andybberry.medium.com/using-ai-to-migrate-years-of-enzyme-units-tests-to-react-testing-library-b62f4dd062f2
• https://slack.engineering/balancing-old-tricks-with-new-feats-ai-powered-conversion-from-enzyme-to-react-testing-library-at-slack/
• https://github.com/slackhq/enzyme-to-rtl-codemod