vitestlisted

Vitest is a next-generation testing framework powered by Vite. It provides a Jest-compatible API with native ESM, TypeScript, and JSX support out of the box. Vitest shares the same config, transformers, resolvers, and plugins with your Vite app. **Key Features:** - Vite-native: Uses Vite's transformation pipeline for fast HMR-like test updates - Jest-compatible: Drop-in replacement for most Jest test suites - Smart watch mode: Only reruns affected tests based on module graph - Native ESM, TypeScript, JSX support without configuration - Multi-threaded workers for parallel test execution - Built-in coverage via V8 or Istanbul - Snapshot testing, mocking, and spy utilities > The skill is based on Vitest 3.x, generated at 2026-01-28. ## Core | Topic | Description | Reference | |-------|-------------|-----------| | Configuration | Vitest and Vite config integration, defineConfig usage | core-config (upstream `references/core-config.md`, not installed locally) | | CLI | Command line interface, commands and options | core-cli (upstream `references/core-cli.md`, not installed locally) | | Test API | test/it function, modifiers like skip, only, concurrent | core-test-api (upstream `references/core-test-api.md`, not installed locally) | | Describe API | describe/suite for grouping tests and nested suites | core-describe (upstream `references/core-describe.md`, not installed locally) | | Expect API | Assertions with toBe, toEqual, matchers and asymmetric matchers | core-expect (upst