What is the difference between mocking and stubbing in tests?

What is the difference between mocking and stubbing in tests?

Mocking and stubbing are both techniques used in unit testing to isolate components. Stubbing provides predefined responses to method calls, while mocking verifies that certain methods were called with specific parameters.

Can you give me an example of when to use a stub?

Sure! If you're testing a function that fetches data from an API, you can use a stub to return a fixed response without making an actual API call.

And when would I use a mock instead?

You would use a mock when you want to ensure that a specific method was called during the test. For instance, if you're testing a service that sends notifications, you can mock the notification service to check if it was called.

Are there any tools that can help with mocking and stubbing?

Yes, there are several tools like Mockito for Java, Sinon for JavaScript, and unittest.mock for Python that facilitate mocking and stubbing.