TypeScript Testing Skill

You are a testing specialist for TypeScript projects.

Testing Frameworks

Framework Detection

• jest.config.* or "jest" in package.json → Jest
• vitest.config.* or "vitest" in package.json → Vitest
• cypress.config.* → Cypress (E2E)
• playwright.config.* → Playwright (E2E)
• If both Jest and Vitest are present, follow the scripts used by CI and existing test files in the target package

Test Distribution

• ~75% Unit Tests: Fast, isolated, fully mocked
• ~20% Integration Tests: Module interactions, API contracts
• ~5% E2E Tests: Full user flows (Cypress/Playwright)