#jest Development Tutorials & Tips | Roast Dev

Crush UI Bugs Before They Crush You: Top Front-End Testing Tools & Strategies

“It worked perfectly on my laptop… until a real user touched it.”That was the moment I truly understood the gap between building a UI and delivering a flawless user experience. I had crafted a ...

16.08.2025 1 Read More

Jest - Solution for "Jest encountered an unexpected toke"

Pre-study Compiling Vs. TranspilingJest Code TransformationJest docs – transformIgnorePatterns Background When running unit tests using Jest, get the error as below ⛶Jest encounte...

05.05.2025 0 Read More

Jest - Mocking Next.js Image to handle dynamic properties in tests

Pre-study Next.js - Image ComponentImporting images used the 'import' keyword for the image 'src' breaks jest test #26749Jest - Manual MocksReact Testing LibraryMDN JavaScript - Rest paramete...

05.05.2025 0 Read More

🧪 React Testing: Tips That Actually Work

1. Test What Users See, Not What Developers Write ⛶// 👎 Don't do this test('component sets loading state', () => { const wrapper = shallow(<UserProfile />); expect(wrapper.s...

19.03.2025 0 Read More

How To Fix the import.meta.env Error in a Vite + Jest Setup

If you’ve worked with Vite for building a React (or other) application and used Jest for testing, you might have encountered an error like: ⛶The 'import.meta' meta-property is only allowed when th...

19.03.2025 0 Read More

Mastering Jest: A Beginner's Guide to JavaScript+NodeJs Testing with Fun Examples -1

Writing code is fun, but debugging is painful! Jest helps us catch bugs early and ensures our JavaScript code works correctly.In this post, I am going to explain how i understood Jest in a most easies...

20.03.2025 0 Read More

Biblioteca de componentes React e typescript, parte 3: testes unitários com Jest e testing library

Introdução English version: React and typescript components lib, part 3: unit tests with Jest and testing libraryNa parte três da série, será incrementada a lib com a definição de test...

24.03.2025 0 Read More

React and typescript components lib, part 3: unit tests with Jest and testing library

Introduction Portuguese version: Biblioteca de componentes React e typescript, parte 3: testes unitários com Jest e testing libraryIn part three of the series, the library will be enhanced w...

24.03.2025 0 Read More

AI as a Coding Tool: A Mixed Experience

Even though AI has been a hot topic in recent times, I had been reluctant to use it in my work as I have always trusted my own research instead of getting an answer directly from someone or something....

30.03.2025 0 Read More

How to Detect Low Test Coverage Files in Jest

How to Detect Low Test Coverage Files in Jest (JavaScript/TypeScript) Through observing our customers' behavior, we've noticed a common challenge when teams want to improve their test coverag...