Enroll Course: https://www.udemy.com/course/typing-the-test-suite/
As developers, we all know the importance of writing clean, robust code. But how do we ensure our code behaves as expected, especially as projects grow in complexity? The answer, of course, lies in testing. If you’re a developer with some experience in JavaScript, TypeScript, Node.js, or React, and you’re looking to dive into the world of testing with Jest, then Udemy’s ‘Typing the Test Suite’ course is an excellent place to start.
This 2-hour course is packed with practical content, designed for intermediate developers who want to get up and running with Jest and TypeScript quickly. The instructor takes a hands-on approach, emphasizing a ‘move fast, break things, then write tests’ philosophy. This iterative process is incredibly effective for learning how to build reliable software.
The course kicks off with the fundamentals of Jest in JavaScript, including a taste of Test-Driven Development (TDD). You’ll learn how to set up your environment, write your first tests, add assertions, group tests with `describe` and `it`, and leverage `watch mode` for immediate feedback. The inclusion of `it.each` for concise test writing is a particularly useful takeaway.
A significant portion of the course is dedicated to practical application. You’ll tackle the String Calculator Kata, applying the concepts learned in the initial sections. This hands-on project solidifies your understanding of writing tests for various scenarios, including error handling and validation.
‘Typing the Test Suite’ then dives deep into Jest’s matchers, covering everything from basic assertions like `toBe` and `toEqual` to more advanced ones like `resolves` and `rejects` for handling promises and errors. The section on mock functions and spies, including `toHaveBeenCalled` and the `done` callback for asynchronous tests, is crucial for building comprehensive test suites.
The course truly shines when it integrates TypeScript. You’ll learn how to use Jest with TypeScript in two distinct environments: Node.js and React. For Node.js development, you’ll build and test an API with Express, exploring concepts like the Jest lifecycle hooks (`beforeAll`, `afterEach`, etc.), type safety with `ts-jest`, and securing your API with JWT.
In the React section, you’ll build a toy React application and learn DOM-based testing using React Testing Library. This covers rendering components, writing assertions with `getByText`, handling asynchronous behavior with `useState` and `useEffect`, mocking network requests with Jest mocks, and more.
Finally, the course touches upon some advanced Jest tips and tricks, including writing custom matchers and mastering module mocking for more robust and reusable tests. The detailed curriculum ensures you’re not just learning theory, but actively applying it.
**Recommendation:**
‘Typing the Test Suite’ is a highly recommended course for any developer looking to add testing to their skillset. Its fast-paced, practical approach, combined with coverage of both JavaScript and TypeScript in Node.js and React environments, makes it an invaluable resource. If you’re ready to embrace TDD and write more reliable code, this course is an excellent investment.
Enroll Course: https://www.udemy.com/course/typing-the-test-suite/