testing-patterns-vitest

Vitest test organization uses feature-based directory structures with *.test.ts files, assertion patterns for common return types, and parallel execution across 4 threads. Group tests by package to improve clarity and maintainability across monorepo packages.

Vitest mocking isolates units through spies and mocks following preset conventions. Apply mocking guidance to control dependencies, verify function calls, and test behavior in isolation while maintaining consistent patterns across your test suite.

Vitest coverage targets enforce statements 75%, branches 50%, functions 60%, and lines 75%. Structure test scaffolding templates to cover critical paths, use assertion conventions for common return types, and organize suites by feature to reach and sustain coverage thresholds.

Testing patterns define standardized test scaffolding templates, preset assertion styles for common return types, and mocking conventions. These patterns speed up test creation, improve reliability, and enforce consistent structure across the monorepo.

Vitest 3.2.4 supports monorepo testing with explicit coverage targets, parallel execution, and file naming conventions. This Skill applies standardized patterns to generate tests, organize suites, and debug failures while meeting 75% coverage across multiple packages.