Chapter 4

1. Testing integrated components allow you to mitigate risk by verifying production behavior when components interact with each other. Using the isolated approach, we would be replacing real dependencies with fake data and responses and, therefore, not mitigate as much risk. Also, in many situations, you can cover more code in fewer tests using the integrated testing approach.
2. You should only use the data-testid attribute as the last resort when other preferred queries methods such as getBy* and findBy* cannot be used to select elements.
3. The act method ensures your tests behave closer to how React updates the browser's DOM. Use act in situations where you need to manually make component updates such as resolving a Promise that React otherwise would not be aware of in your test. React Testing Library automatically wraps components in act eliminating the need to manually wrap all code that updates the component in most scenarios, such as click events.

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