/testing

name: testing
description: Write and maintain tests with Bun units and Rstest integrations, mock utilities, and Zustand store testing patterns.

Testing

Write reliable tests with Bun units and Rstest integrations.

Activation Conditions

• Writing or modifying tests
• Debugging test failures
• Setting up mocks
• Questions about test configuration

Quick Reference

| Action | Rule | |--------|------| | Choose test type | `test-unit-vs-integration.md` | | Mock modules | `test-mock-patterns.md` | | Test stores | `test-zustand-stores.md` | | Mock Connect APIs | `mock-transport.md` | | Skip UI rendering tests | `no-ui-rendering-tests.md` |

Commands

bun run test              # All tests (CI default)
bun run test:ci           # Sequential for CI
bun run test:unit         # Unit tests only
bun run test:integration  # Integration tests only
bun run test:unit:watch   # Bun watch mode
bun run test:watch        # Integration watch mode
bun run test:coverage     # Coverage report

Key Points

• `.test.ts` = Bun unit, `.test.tsx` / `.integration.test.ts` = Rstest integration (Happy DOM)
• Always use `test-utils/test-utils.tsx` for React component tests
• Test that features are fully wired: UI elements must connect to actual functionality

Feature Completeness Testing

When implementing interactive features (buttons, forms, etc.):

• Verify event handlers call the correct functions with proper parameters
• Test that AbortSignals, callbacks, and other "plumbing" are passed through
• Don't assume UI presence means functionality works - test the connection

When to Use This Skill

• Writing `.test.ts` or `.test.tsx` files
• Mocking modules, stores, or transports
• Component behavior tests

**NOT for:** Multi-page user workflows → use [e2e-tester](../e2e-tester/SKILL.md)

Rules

See `rules/` directory for detailed guidance.