FEATURE_TESTING_REQUIREMENTS.md

Feature Testing Requirements

Mandatory testing standards for all new features in the NextSaaS system

Overview

Every new feature added to the NextSaaS system MUST be fully tested at multiple levels before deployment. This document outlines the bare minimum testing requirements that are non-negotiable for any feature contribution.

🚫 No Feature Ships Without Tests

RULE: No feature can be merged or deployed without complete test coverage across all applicable testing levels.

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Testing Levels & Requirements

1. 📋 Unit Testing (MANDATORY)

Scope: Test individual components, functions, and modules in isolation.

Minimum Requirements:

• ✅ 80% code coverage minimum (branches, functions, lines, statements)
• ✅ All component variants and props tested
• ✅ All function parameters and return values tested
• ✅ Error handling and edge cases covered
• ✅ State management logic validated

What Must Be Tested:

For UI Components:

describe('ComponentName', () => {
  // REQUIRED: Basic rendering
  test('renders correctly with default props', () => {})

  // REQUIRED: All variants
  test.each(['primary', 'secondary', 'destructive'])(
    'renders %s variant',
    () => {}
  )

  // REQUIRED: All states
  test('handles disabled state', () => {})
  test('handles loading state', () => {})
  test('handles error state', () => {})

  // REQUIRED: User interactions
  test('handles click events', () => {})
  test('handles keyboard navigation', () => {})

  // REQUIRED: Accessibility
  test('meets accessibility standards', async () => {
    await testAccessibility(component)
  })

  // REQUIRED: Ref forwarding (if applicable)
  test('forwards ref correctly', () => {})
})

For Business Logic:

describe('FeatureService', () => {
  // REQUIRED: Core functionality
  test('processes data correctly', () => {})

  // REQUIRED: Error scenarios
  test('handles invalid input gracefully', () => {})
  test('throws appropriate errors', () => {})

  // REQUIRED: Edge cases
  test('handles empty data sets', () => {})
  test('handles maximum limits', () => {})
})

For Hooks:

describe('useFeatureHook', () => {
  // REQUIRED: Initial state
  test('initializes with correct default state', () => {})

  // REQUIRED: State updates
  test('updates state correctly on actions', () => {})

  // REQUIRED: Cleanup
  test('cleans up resources on unmount', () => {})
})

2. 🔗 Integration Testing (MANDATORY)

Scope: Test how components work together and interact with external systems.

Minimum Requirements:

• ✅ Component composition and data flow tested
• ✅ API integration points validated
• ✅ Database operations verified (with mocks)
• ✅ Authentication flows tested
• ✅ Multi-tenant scenarios covered

What Must Be Tested:

For Feature Workflows:

describe('FeatureWorkflow Integration', () => {
  // REQUIRED: Complete user flows
  test('completes feature workflow successfully', async () => {
    // Test entire user journey from start to finish
  })

  // REQUIRED: API interactions
  test('handles API responses correctly', async () => {
    // Mock API calls and test responses
  })

  // REQUIRED: Error recovery
  test('recovers from API failures gracefully', async () => {
    // Test network errors, 500s, etc.
  })

  // REQUIRED: State persistence
  test('persists state across page refreshes', async () => {
    // Test local storage, session storage, etc.
  })
})

For Multi-tenant Features:

describe('Multi-tenant Integration', () => {
  // REQUIRED: Tenant isolation
  test('isolates data between tenants', async () => {})

  // REQUIRED: Permission checks
  test('enforces tenant-specific permissions', async () => {})

  // REQUIRED: Organization switching
  test('handles organization context changes', async () => {})
})

3. 🌐 End-to-End Testing (MANDATORY)

Scope: Test complete user journeys from browser to database.

Minimum Requirements:

• ✅ Critical user paths tested end-to-end
• ✅ Cross-browser compatibility verified
• ✅ Mobile responsiveness validated
• ✅ Performance benchmarks established
• ✅ Visual regression tests implemented

What Must Be Tested:

For User Journeys:

describe('Feature E2E Tests', () => {
  // REQUIRED: Happy path
  test('user can complete feature successfully', async ({ page }) => {
    // Test complete user workflow
    await page.goto('/feature')
    await page.click('[data-testid="start-feature"]')
    await page.fill('[data-testid="input"]', 'test data')
    await page.click('[data-testid="submit"]')
    await expect(page.locator('[data-testid="success"]')).toBeVisible()
  })

  // REQUIRED: Error scenarios
  test('handles validation errors properly', async ({ page }) => {
    // Test form validation, error messages
  })

  // REQUIRED: Navigation flows
  test('navigates between feature screens correctly', async ({ page }) => {
    // Test routing and navigation
  })
})

For Cross-browser Compatibility:

// REQUIRED: Test on all supported browsers
;['chromium', 'firefox', 'webkit'].forEach(browserName => {
  test.describe(`${browserName} browser tests`, () => {
    test('feature works correctly', async ({ page }) => {
      // Test core functionality
    })
  })
})

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🎯 Feature-Specific Requirements

Authentication Features

• Unit: Auth components, validation functions, token handling
• Integration: Auth flows with API, session management, redirect logic
• E2E: Complete login/signup/logout flows, password reset, social auth

CRUD Operations

• Unit: Form validation, data transformation, error handling
• Integration: API calls, optimistic updates, cache invalidation
• E2E: Create → Read → Update → Delete workflows

Dashboard/Analytics Features

• Unit: Chart components, data processing, calculations
• Integration: Data fetching, real-time updates, filtering
• E2E: Dashboard loading, interaction, data drill-down

Payment/Billing Features

• Unit: Price calculations, currency formatting, validation
• Integration: Stripe integration, webhook handling, state updates
• E2E: Complete payment flow, subscription management

Multi-tenant Features

• Unit: Permission checks, data filtering, tenant context
• Integration: RLS policies, organization switching, member management
• E2E: Tenant isolation verification, invite flows

---

📊 Quality Gates

Before Code Review:

• All unit tests pass locally
• Integration tests pass with mocked dependencies
• E2E tests pass in development environment
• Code coverage meets 80% minimum threshold
• No accessibility violations detected

Before Merge:

• All CI/CD tests pass
• Visual regression tests approved
• Performance benchmarks within acceptable limits
• Bundle size increases justified and documented

Before Deployment:

• E2E tests pass in staging environment
• Load testing completed (for critical features)
• Monitoring and alerting configured
• Rollback plan documented

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🛠️ Testing Tools & Setup

Required Test Files Structure:

src/
├── components/
│   └── MyFeature/
│       ├── MyFeature.tsx
│       ├── MyFeature.test.tsx        # Unit tests
│       ├── MyFeature.visual.test.ts  # Visual regression
│       └── index.ts
├── hooks/
│   └── useMyFeature/
│       ├── useMyFeature.ts
│       ├── useMyFeature.test.ts      # Unit tests
│       └── index.ts
├── services/
│   └── myFeatureService/
│       ├── myFeatureService.ts
│       ├── myFeatureService.test.ts  # Unit + Integration
│       └── index.ts
└── __tests__/
    ├── integration/
    │   └── MyFeature.integration.test.ts
    └── e2e/
        └── MyFeature.e2e.test.ts

Test Commands:

# Run all tests for a feature
npm run test -- --testPathPattern=MyFeature

# Run specific test types
npm run test:unit
npm run test:integration
npm run test:e2e

# Coverage for specific feature
npm run test:coverage -- --testPathPattern=MyFeature

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📋 Feature Testing Checklist

Before Starting Development:

• Identify all test scenarios (happy path, edge cases, errors)
• Plan test data requirements
• Determine external dependencies to mock
• Write test plan for review

During Development:

• Write unit tests alongside implementation (TDD approach)
• Create integration tests for API interactions
• Implement visual regression tests for UI changes
• Test accessibility with screen readers and keyboard navigation

Before Code Review:

• All tests pass locally
• Code coverage meets requirements
• Tests cover all acceptance criteria
• Error scenarios properly tested
• Performance implications considered

During Code Review:

• Test quality reviewed alongside code quality
• Test scenarios validated against requirements
• Edge cases adequately covered
• Test maintainability assessed

Before Deployment:

• E2E tests pass in staging
• Performance benchmarks established
• Monitoring configured for new feature
• Documentation updated

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🚨 Non-Negotiables

What Will Block Your Feature:

1. Missing unit tests → Feature rejected
2. Coverage below 80% → Feature rejected
3. No integration tests for API calls → Feature rejected
4. No E2E tests for user flows → Feature rejected
5. Accessibility violations → Feature rejected
6. Visual regressions → Feature rejected
7. Breaking existing tests → Feature rejected

Enforcement:

• CI/CD Pipeline: Automatically blocks merges without proper tests
• Code Review: Reviewers must verify test coverage and quality
• Deployment Gates: Staging tests must pass before production release

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📚 Resources & Examples

Testing Utilities:

• Unit Testing: Use test-utils.tsx for component testing
• Mocking: Use established mock patterns for Supabase, Auth
• Accessibility: Use testAccessibility() helper function
• Visual Testing: Use Playwright screenshot comparison

Example Test Files:

• packages/ui/src/atoms/buttons/Button.test.tsx - Component unit tests
• packages/auth/src/hooks/useAuth.test.ts - Hook testing
• e2e/auth/login.e2e.test.ts - End-to-end user flows

Documentation:

• Testing Guide
• Authentication Testing
• Multi-tenant Testing

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Remember: Testing is not optional. It's an integral part of feature development that ensures system reliability, maintainability, and user experience quality.