What are mocking and stubbing in software testing?

What are mocking and stubbing in software testing?

Mocking and stubbing are techniques used in unit testing to isolate components. Mocking creates a fake object that simulates the behavior of real objects, while stubbing provides predefined responses to calls made during the test.

Why would I use mocking instead of just using real objects?

Using mocks allows you to test components in isolation, ensuring that tests are not dependent on external systems or states, which can lead to more reliable and faster tests.

Can you give me an example of when to use stubbing?

Sure! If you have a function that fetches data from an API, you can stub that function to return a fixed response, allowing you to test how your code handles that data without making actual API calls.

Are there any libraries you recommend for mocking and stubbing?

Yes! Popular libraries include Mockito for Java, Moq for .NET, and Sinon.js for JavaScript. They provide powerful tools for creating mocks and stubs.