- Mock IntersectionObserver in Jest Setup· 4 min read
Fix `IntersectionObserver is not defined` in Jest by adding a clean global mock in `jest.setup.ts`. Includes TypeScript-safe setup and a test example.
- Fix Jest Matchmedia Not Defined· 3 min read
Fix the 'window.matchMedia is not a function' error in Jest tests with a quick mock setup.
- How to Solve the "ResizeObserver is Not Defined" Error in Jest Tests· 2 min read
Resolve the 'ResizeObserver is not defined' error in Jest tests. Our guide shows how to mock ResizeObserver for hassle-free unit testing.
- Testing Next.js Image Component· 7 min read
Simple way to test Next.js Image in Jest by mocking it as a plain img tag, plus checks and common mistakes.
- Testing the next-i18next Library with Jest· 6 min read
Simple way to test next-i18next in Jest by mocking translation hooks so component tests stay focused and stable.
- How to Resolve 'Cannot use import statement outside a module' Error when Mocking Swiper JS with Jest· 7 min read
Fix Jest "Cannot use import statement outside a module" when mocking Swiper by adjusting transformIgnorePatterns.
- Resolving Jest Error with EMFILE Too Many Open Files· 7 min read
Fix Jest EMFILE too many open files error with practical config changes, watcher tips, and stable CI settings.