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WeAreDevelopers LIVE • Jun 15, 2022

Yes, You Need to Unit Test your JavaScript. Here's How.

James Bender

Terrified that a simple edit will break your entire JavaScript application? Discover how strict test-driven development prevents regressions, stops over-engineering, and accelerates long-term delivery.

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#1 about 3 min

The problem with missing unit tests in JavaScript

The rapid churn of frameworks often distracts teams from implementing foundational code quality checks.

#2 about 3 min

Confronting common excuses for avoiding unit testing

Development teams frequently abandon testing methodologies due to perceived scale irrelevance or strict project timelines.

#3 about 3 min

Justifying testing costs to project decision makers

While test creation initially slows development sprints, it prevents costly maintenance delays before launch.

#4 about 6 min

Reversing traditional specification workflows with proactive testing

Defining expected outcomes as code forces developers to consume their own interfaces prior to deployment.

#5 about 7 min

Defining the core characteristics of robust unit tests

Effective logic evaluations must operate in total isolation to pinpoint failures without horizontal or vertical dependencies.

#6 about 5 min

Navigating the red green refactor development cycle

Writing minimal code to clear a failing validation provides a safe foundation for future optimization.

#7 about 5 min

Exploring testing environments with Jasmine and Jest

Upgrading to multi-threaded runtime environments drastically reduces performance bottlenecks across extensive application repositories.

#8 about 6 min

Building a fundamental test function using Jest

Structuring direct expected logic prevents false block failures by targeting distinct and isolated variants.

#9 about 11 min

Structuring behavior driven development stories with describe blocks

Constructing hierarchical human readable specification code simplifies collaboration barriers with business analysts.

#10 about 7 min

Adding iterative logic to pass progressive test blocks

Resolving incremental specification demands ensures new component operations adhere strictly to established architectural requirements.

#11 about 4 min

Implementing component and integration validation in React applications

Testing internal state transitions provides more reliable pipeline outcomes than querying brittle virtual DOM elements.

#12 about 5 min

Identifying scenarios where strict test driven development limits agility

Massive legacy codebases harboring deep architectural anti-patterns resist isolated dependency mocking without major logic refactors.

Matching moments

3:47 min

Tracing the evolution of unit and integration testing

Daniel Afonso Daniel Afonso · WWC 2025

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Building a minimal training simulator with JavaScript and Jest

Mirjam Aulbach · WWC 2022

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Implementing unit and snapshot testing using Jest framework

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1:18 min

Reflecting on the core motivations for writing tests

Daniel Afonso Daniel Afonso · WWC 2025

44 sec

Treating unit tests as essential development tools

Annelore Egger Annelore Egger · WWC 2025

4:00 min

Adopting test-driven design as a strategic development methodology

Mirjam Aulbach · WWC 2022

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