Testing React Server Components in Next.js

React Server Components (RSC) represent a meaningful shift in how React applications are structured. By moving rendering to the server, they eliminate unnecessary client-side JavaScript, enable direct data access without an API layer, and improve both performance and SEO. Next.js embraces this model fully — in the app directory, every component is a server component by default. The tradeoff is that testing becomes more involved. The same server-side nature that makes RSCs powerful also makes them incompatible with the client-side testing tools most React developers reach for first. This article walks through what you need to know: the unique challenges RSCs pose for testing, how to configure your environment, and how to write tests that actually reflect how your components behave in production. Understanding React Server Components Before writing tests, it helps to understand what distinguishes RSCs from client components: No client-side state or lifecycle methods. RSCs cannot use useS