Test Driven Development in TypeScript & Jest | CodeSignal Learn

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intermediate

Test Driven Development in TypeScript & Jest

Software Engineering

4 courses

101 practices

13 hours

Master TDD principles for TypeScript by writing clean, testable code with Jest. Learn mocking, stubbing, and test doubles, and dive into refactoring techniques for maintainable code. Boost efficiency, reduce bugs, and build robust, scalable applications with this hands-on course.

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Verified skills you'll gain

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Computer Science Fundamentals

INTERMEDIATE

Programming, Algorithms, and Data Structures

Tools you'll use

Jest

TypeScript

Course 1

Foundations of TDD in TypeScript and Jest: The Principles

6 lessons

27 practices

This course introduces Test-Driven Development (TDD) for TypeScript projects, covering the Red-Green-Refactor workflow, TDD mindset, and setup with Jest. Learn best practices like SOLID principles and dependency injection, and explore TDD's impact on code quality and speed compared to traditional approaches.

Course 2

Red-Green-Refactor: Practicing TDD with JavaScript & Jest

5 lessons

27 practices

This course focuses on practicing the core TDD workflow: "Red-Green-Refactor." You'll write failing tests (Red), implement code to pass them (Green), and refactor while keeping tests passing (Refactor). No new concepts are introduced—just hands-on practice with various requirements to sharpen your TDD skills.

Course 3

Isolating Dependencies with Test Doubles with TypeScript & Jest

5 lessons

25 practices

Discover the pivotal role of test doubles in modern software testing. This introductory session will guide you through the essentials of dummies, stubs, spies, mocks, and fakes. Learn how these powerful tools help you isolate units under test, control behavior, and build reliable, fast, and maintainable tests. Step into the world of test doubles and elevate your software development skills.

Course 4

Refactoring by Leveraging Your Tests with TypeScript & Jest

5 lessons

22 practices

This course focuses on the Refactor step in TDD, teaching developers to spot code smells and resolve them through refactoring. Using real-world examples, you'll identify common issues, apply refactoring techniques, and ensure functionality is preserved with existing tests.

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