James Bender
Yes, You Need to Unit Test your JavaScript. Here's How.
#1about 7 minutes
Why developers avoid unit testing JavaScript
Common excuses for not unit testing are addressed by framing tests as a long-term investment that prevents project slowdowns.
#2about 5 minutes
Understanding the Test-Driven Development workflow
TDD inverts the traditional development process by using specifications to write automated tests before writing the implementation code.
#3about 7 minutes
The core characteristics of a good unit test
Effective unit tests are isolated from dependencies, targeted to a single scenario, and repeatable regardless of external factors.
#4about 5 minutes
Applying the red-green-refactor TDD cycle
The core TDD loop involves writing a failing test (red), writing minimal code to pass it (green), and then improving the code's design (refactor).
#5about 2 minutes
Choosing a JavaScript testing framework: Jest vs Jasmine
Jest is recommended over Jasmine primarily for its performance benefits, as it runs tests in a multi-threaded environment.
#6about 8 minutes
Writing your first basic unit test with Jest
A live coding demonstration introduces the basic Jest syntax, including the `test`, `expect`, and `toBe` functions for a simple sum operation.
#7about 14 minutes
Live coding a Tic-Tac-Toe game using TDD
This demonstration builds a simple game engine by following the red-green-refactor cycle and using BDD-style tests with `describe` and `it`.
#8about 2 minutes
Practical next steps for adopting unit testing
Actionable advice for teams includes starting with new features, practicing daily, sharing knowledge, and measuring code coverage.
#9about 9 minutes
Audience Q&A on testing strategies
Questions from the audience are answered, covering topics like integration testing in React, handling front-end tests, and involving product teams.
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Matching moments
00:58 MIN
Why developers often view unit testing as a chore
Test-reduction - Doing more with less
1:28:47 MIN
Recap and practical advice for testing applications
Test Driven Development with JavaScript
03:20 MIN
Why JavaScript and TypeScript dominate modern development
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36:52 MIN
Q&A on BDD and testing untestable code
How to TDD in legacy code
10:27 MIN
Building a testing foundation with unit tests
Trunk-Based Development at Scale: Real-World Insights from a High-Traffic Luxury E-Commerce Platform
11:17 MIN
Writing unit tests for specific accessibility concerns
Accessibility Test Driven Development
26:41 MIN
Summary of key trends in modern JavaScript testing
The 2025 State of JavaScript Testing
00:05 MIN
Identifying the most common pain points in JavaScript testing
The 2025 State of JavaScript Testing
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