A wise developer once said “All code is guilty until proven innocent.” Testing your code is critical and Lightning Web Components makes no exception to that rule. Watch this session and learn how to test your components. You’ll get an overview of the testing environment including the Jest framework. We’ll demonstrate how you can test components in complete isolation with Apex mocking.

Trailhead Live: https://trailhead.salesforce.com/live/videos/a2r3k000001WFPk/testing-lightning-web-components
Blog post: https://developer.salesforce.com/blogs/2019/03/unit-test-lightning-web-components-with-jest.html
GitHub repo: https://github.com/trailheadapps/lwc-recipes