How we migrated from Enzyme to React testing library

How we migrated from Enzyme to React testing library
10 minutes by Charley Pugmire

Enzyme was the standard for testing React apps but became outdated when it stopped supporting React 18 features. HubSpot migrated over 76,000 tests from Enzyme to React Testing Library over two and a half years. They used runtime metrics to categorize packages by test complexity and prioritized smaller migrations first.

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Testing async React RSC components
7 minutes by HowToTestFrontEnd

Testing React Server Components is challenging because of their async behavior. The usual approach is to use end-to-end tests like Playwright or Cypress instead of unit tests. For unit testing with React testing library, you can use render(await Component()) for simple async components.

Just JavaScript
6 minutes by Pedro Cattori

Pedro defines "just JavaScript" as code that works without custom transforms. He argues that it means you should understand what your program does and be able to refactor code normally without breaking things. TypeScript and JSX get a pass because they're now widely supported by JavaScript runtimes. React Router almost qualifies but uses special route module exports that change where code runs.

Tooltip components should not exist
4 minutes by Dominik Dorfmeister

Design systems shouldn't provide generic tooltip components because they're too easy to misuse. Developers often add tooltips to non-interactive elements that can't receive keyboard focus, making them inaccessible. Instead Dominik suggests, design systems should offer higher-level components like buttons with optional title props or dedicated info icons. This approach ensures consistent, accessible tooltip usage across teams.

How I learned React as a junior developer
6 minutes by Ellenoor Bok

Ellenoor shares her journey from a confused junior developer learning React to confidently building full-stack applications with Next.js. She describes how early struggles with hooks led her to discover the power of clear prompting, context-setting, and analogy-based explanations when working with an AI coding assistant. By asking focused questions and building understanding step by step, she developed an effective learning method and a reliable partnership with AI as a mentor.

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javascript

• Esbuild's XSS Bug that Survived 5 Billion Downloads
• Error chaining in JavaScript

webdev

• The Range Syntax Has Come to Container Style Queries and if()
• Six Things You Could Do With Developer Tools

And the most popular article from the last issue was:

• React 19.2: React in its sigma era