Unit Testing  involves testing individual components or functions as well as their elements to ensure they behave as expected.    The benefits of unit testing is to verify that each unit of code such as the component or function works correctly in isolation from the rest of the application.

Testing Libraries: The popular testing libraries for React include Jest library. Jest is a testing framework and the testing library provides utilities for testing React Components. Jest is also pre-configured with the React Framework.

Writing Test: Create a seperate folder in your project (e.g ‘–test–‘ or ‘src/–test–‘) to store your test files. Test files should have the same name as the component or module being tested.

Test Structure: Each test file typically contains one or more test suites (‘describe’,blocks) and individual test cases (‘it’, or ‘test’blocks). Use Assertions (e.g ‘expect’ statements) to verify that the component or function behaves as expected.

Rendering Components: Use tools like Testing library’s render function to render React components in a test environment. Query the rendered component or function to make assertions about the state, props and rendered outputs.

Mocking: Jest library capabilities are also used to isolate components from external dependencies such as API calls or other modules. Mocking will allow you to control the behaviour of external dependencies during testing.

In the tutorial below i will be utilizing a Jest Library with a React Application.