The Complete React Developer Course (with Hooks and Redux) - Testing Expenses Reducer

The video tutorial covers testing the expenses reducer in a JavaScript application. It begins with setting up test cases for the default state and progresses to creating fixtures for test data. The tutorial then demonstrates writing test cases for removing expenses by ID, including scenarios where the ID is not found. Finally, it covers adding and editing expenses, ensuring the reducer functions as expected. The tutorial emphasizes the importance of using fixtures for consistent test data and highlights common mistakes in writing test assertions.

What are the key components to include in an action object for adding an expense?

What is the expected outcome when editing an expense with a valid ID?

Explain how to set up a test case for editing an expense.

How do you ensure that the expenses array is unchanged when an invalid ID is used?