Articles tagged with #Testing
A curated list of engineering series, deep dives, and notes related to #Testing.
Coverage Engines: Bytecode Coverage via V8 AST Counters vs AST Instrumentation with Istanbul
Analyze code coverage providers in Vitest: V8 native bytecode counters vs Istanbul AST instrumentation.
Vitest Browser Mode: Executing Tests in Real Chromium, Firefox, and WebKit Engines
Explore Vitest Browser Mode: executing component tests in real browser engines with native DOM APIs.
Snapshot Testing Engine: AST Serializers, File Formatting, and Inline Snapshots
Learn how Vitest formats, updates, and serializes snapshots using custom snapshot serializers.
Fake Timers, Microtasks, and Event Loop Time Manipulation
Master Vitest's fake timer engine powered by @sinonjs/fake-timers to test intervals, timeouts, and dates.
Web Testing Strategy: Test Pyramid, MSW Mocking, Playwright E2E, and Visual Regression
Master web testing architecture. Learn the frontend Testing Pyramid, MSW Service Worker network mocking, Playwright E2E, and visual regression.
Assertion Engine Mechanics: First-Principles Comparison of Vitest Matchers
A first-principles deep dive into Vitest's assertion engine. Compare toBe, toEqual, toStrictEqual, toContain, toMatchObject, and spy matchers down to V8 heap pointers and prototype resolution.
Vitest Configuration Mechanics: Merging vite.config.ts, test.include, and Environment Drivers
Learn how Vitest merges Vite configs, configures DOM environments (happy-dom/jsdom), and customizes test includes.
Vitest Architecture & Modern Testing Systems: Series Introduction
Master Vitest from first principles: Vite transform pipelines, tinypool isolation, module hoisting, fake timers, and custom reporters.