@matheus-releaserun

React Testing Library Reference: Queries, userEvent, Async, MSW and Accessibility

Mar 14 · 2 min read · React Testing Library reference — test what users see, not how your components work. The guiding rule: test behavior, not implementation // WRONG: testing internal state expect(wrapper.state().isOpen).toBe(true); // CORRECT: testing what the user se...

Jest Reference: Config, Matchers, Mocking, Async Tests and Snapshots

Mar 14 · 2 min read · Jest reference — mocking, snapshots, and the config that actually works with TypeScript. ts-jest vs babel-jest: choose your TypeScript strategy // ts-jest: slower but type-checks during tests preset: "ts-jest", // babel-jest: faster, strips types wi...

Webpack 5 Reference: Config, Loaders, Code Splitting, Dev Server and Module Federation

Mar 14 · 2 min read · Webpack 5 reference — the config patterns that actually matter. mode: "production" gives you a lot for free module.exports = { mode: "production" }; // Enables: minification (terser), tree shaking, scope hoisting, compressed output // Always set mode...

SWR Reference: useSWR, Mutations, Infinite Scroll, Revalidation and Next.js

Mar 14 · 2 min read · SWR reference — stale-while-revalidate, mutations, and infinite scroll. The mental model: serve cache immediately, revalidate in background const { data, isLoading, isValidating } = useSWR<User>("/api/me", fetcher); // isLoading = true only on first ...

Nx Reference: Workspace Setup, Caching, Project Graph, Generators and Nx Cloud CI

Mar 14 · 2 min read · Nx reference — computation caching, affected builds, and the project graph. The core value: hash inputs, cache outputs, skip unchanged work Nx hashes your source files, dependencies, and config for each task. If nothing changed since the last run, it...