React Testing Library Best Practices

Comprehensive testing guide for React components using Testing Library, designed for AI agents and LLMs. Contains 43 rules across 9 categories, prioritized by impact to guide test writing and code review.

When to Apply

Reference these guidelines when:

• Writing new component tests with React Testing Library
• Selecting queries (getByRole, getByLabelText, etc.)
• Handling async operations in tests (findBy, waitFor)
• Simulating user interactions (userEvent)
• Reviewing tests for anti-patterns and implementation detail testing

Rule Categories by Priority