designing-tests

name	designing-tests
description	Designs and implements testing strategies for any codebase. Use when adding tests, improving coverage, setting up testing infrastructure, debugging test failures, or when asked about unit tests, integration tests, or E2E testing.

Designing Tests

When to Load

• Trigger: Adding tests, test strategy planning, improving coverage, setting up testing infrastructure
• Skip: Non-test code changes where testing is not part of the task

Test Implementation Workflow

Copy this checklist and track progress:

Test Implementation Progress:
- [ ] Step 1: Identify what to test
- [ ] Step 2: Select appropriate test type
- [ ] Step 3: Write tests following templates
- [ ] Step 4: Run tests and verify passing
- [ ] Step 5: Check coverage meets targets
- [ ] Step 6: Fix any failing tests

Testing Pyramid

Apply the testing pyramid for balanced coverage:

        /\
       /  \     E2E Tests (10%)
      /----\    - Critical user journeys
     /      \   - Slow but comprehensive
    /--------\  Integration Tests (20%)
   /          \ - Component interactions
  /------------\ - API contracts
 /              \ Unit Tests (70%)
/________________\ - Fast, isolated
                   - Business logic focus

Framework Selection

JavaScript/TypeScript

Type	Recommended	Alternative
Unit	Vitest	Jest
Integration	Vitest + MSW	Jest + SuperTest
E2E	Playwright	Cypress
Component	Testing Library	Enzyme

Python