chess/docs/testing/quality-criteria.md

Quality Criteria and Acceptance Standards

Overview

This document defines the quality gates and acceptance criteria that must be met before code can be merged and released.

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1. Code Quality Metrics

1.1 Code Coverage

Minimum Thresholds:

{
  "statements": 85,
  "branches": 80,
  "functions": 85,
  "lines": 85
}

Coverage by Component:

Component	Minimum Coverage
Chess Engine (rules)	95%
Game State Manager	90%
UI Components	80%
Utilities	85%
Event Handlers	80%

Exclusions:

• Configuration files
• Type definitions
• Constants files
• Third-party integrations

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1.2 Code Complexity

Cyclomatic Complexity:

• Maximum per function: 10
• Maximum per file: 50
• Warning threshold: 7

Cognitive Complexity:

• Maximum per function: 15
• Recommend refactoring above: 10

File Size Limits:

• Maximum lines per file: 500
• Warning threshold: 300
• Test files: 1000 (allowed for comprehensive test suites)

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1.3 Code Style

Linting:

• ESLint: Zero errors
• Warnings: Max 5 per 1000 lines
• Disabled rules: None (all rules enforced)

Formatting:

• Prettier: 100% formatted
• Line length: 100 characters
• Indentation: 2 spaces
• Trailing commas: Required
• Semicolons: Required

TypeScript (if applicable):

• Strict mode: Enabled
• No implicit any: Enforced
• Type coverage: >90%

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2. Performance Criteria

2.1 Load Time Performance

Initial Page Load:

• Time to First Byte (TTFB): <300ms
• First Contentful Paint (FCP): <1.5s
• Largest Contentful Paint (LCP): <2.5s
• Time to Interactive (TTI): <3.5s
• Cumulative Layout Shift (CLS): <0.1

Bundle Size:

• Main bundle (gzipped): <150KB
• JavaScript total: <250KB
• CSS total: <30KB
• Images: WebP format, <500KB total

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2.2 Runtime Performance

Move Calculation:

• Legal move generation: <100ms
• Check detection: <50ms
• Checkmate detection: <200ms
• Complex positions (30+ pieces): <150ms

UI Rendering:

• Frame rate during animations: 60 FPS (16.67ms per frame)
• UI update after move: <16ms
• Board rotation animation: <500ms
• Piece drag responsiveness: <10ms

Memory Usage:

• Initial memory: <20MB
• Peak during gameplay: <50MB
• Memory leak tolerance: 0 (no leaks allowed)
• Garbage collection frequency: <1 per minute

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2.3 Network Performance

Offline Functionality:

• Full game playable offline: Required
• Service Worker: Implemented
• Cache strategy: Cache-first for static assets

Data Transfer (if applicable):

• API response time: <200ms
• WebSocket latency: <50ms
• Compressed responses: Required

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3. Functional Criteria

3.1 Chess Rules Compliance

Core Rules:

• All piece movements: 100% accurate
• Castling rules: Fully compliant
• En passant: Correctly implemented
• Pawn promotion: All pieces supported
• Check/Checkmate: Correctly detected
• Stalemate: Correctly detected

Advanced Rules:

• Fifty-move rule: Implemented
• Threefold repetition: Detected
• Insufficient material: Detected
• Dead position: Detected

FIDE Compliance:

• Laws of Chess conformance: 100%
• Standard algebraic notation (SAN): Supported
• Portable Game Notation (PGN): Import/export

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3.2 User Experience

Interaction:

• Drag-and-drop: Smooth, no lag
• Click-to-move: Responsive
• Move validation feedback: Immediate (<100ms)
• Error messages: Clear, actionable

Visual Feedback:

• Valid moves highlighted: Required
• Check indication: Visual + auditory
• Last move highlight: Required
• Captured pieces display: Recommended

Responsive Design:

• Mobile (320px-767px): Fully functional
• Tablet (768px-1023px): Optimized layout
• Desktop (1024px+): Enhanced features
• Touch targets: Minimum 44x44px

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4. Accessibility Standards

4.1 WCAG 2.1 Level AA Compliance

Perceivable:

• Color contrast: Minimum 4.5:1 (normal text), 3:1 (large text)
• Non-color indicators: Required for all states
• Alt text: All images and icons
• Captions: For any video/audio content

Operable:

• Keyboard navigation: 100% functionality
• No keyboard traps: Required
• Focus visible: Clear indicators
• Time limits: Adjustable or disabled

Understandable:

• Language attribute: Set correctly
• Consistent navigation: Required
• Error identification: Clear messages
• Labels/instructions: All inputs

Robust:

• Valid HTML: W3C compliant
• ARIA attributes: Correctly used
• Compatible assistive tech: Screen readers, voice control

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4.2 Keyboard Accessibility

Required Controls:

• Tab: Navigate between elements
• Arrow keys: Navigate board
• Enter/Space: Select and move pieces
• Escape: Cancel selection
• Numbers: Quick piece selection (optional)

Focus Management:

• Visible focus indicator: Required
• Logical tab order: Enforced
• Skip links: Provided
• Focus trapping in modals: Implemented

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4.3 Screen Reader Support

Announcements:

• Move notifications: "White pawn e2 to e4"
• Game state: "White in check"
• Captured pieces: "Black knight captured"
• Game end: "Checkmate. Black wins."

Labels:

• All interactive elements: Labeled
• Board squares: Descriptive (e.g., "e4, white square, empty")
• Pieces: "White pawn on e2"

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5. Browser Compatibility

5.1 Desktop Browsers

Fully Supported:

• Chrome 100+ (latest, -1, -2 versions)
• Firefox 100+ (latest, -1)
• Safari 15+ (latest, -1)
• Edge 100+ (latest)

Graceful Degradation:

• Chrome 90-99: Core features
• Firefox 90-99: Core features
• Safari 14: Core features

Not Supported:

• Internet Explorer: Not supported
• Opera Mini: Not supported

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5.2 Mobile Browsers

Fully Supported:

• iOS Safari 15+ (iPhone, iPad)
• Chrome Android 100+
• Samsung Internet 15+

Touch Optimization:

• Touch targets: Minimum 44x44px
• Gestures: Intuitive and documented
• Orientation: Both portrait and landscape

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6. Security Criteria

6.1 Input Validation

Client-Side:

• All user input: Sanitized
• Move validation: Server-side (if multiplayer)
• XSS prevention: Required
• CSRF protection: Implemented (if applicable)

Data Storage:

• LocalStorage: Only non-sensitive data
• No credentials in localStorage: Enforced
• Encrypted storage: For sensitive data (if any)

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6.2 Dependency Security

Vulnerability Scanning:

• npm audit: Zero high/critical vulnerabilities
• Snyk/Dependabot: Enabled
• Automated updates: Security patches

Allowed Severity:

• Critical: 0
• High: 0
• Medium: <3
• Low: <10

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7. Testing Criteria

7.1 Test Coverage

Test Types Distribution:

• Unit tests: 70% of test suite
• Integration tests: 20% of test suite
• E2E tests: 10% of test suite

Test Quality:

• Flaky tests: 0 (must be fixed immediately)
• Test execution time: <2 minutes (all tests)
• Test isolation: 100% (no dependencies)

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7.2 Test Execution

Pre-Commit:

• Unit tests: 100% pass rate
• Linting: Zero errors
• Type checking: Zero errors

Pre-Merge:

• All tests: 100% pass rate
• Coverage check: Pass
• E2E smoke tests: Pass

Pre-Release:

• Full E2E suite: 100% pass
• Cross-browser tests: Pass
• Accessibility audit: Pass
• Performance audit: Pass

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8. Documentation Criteria

8.1 Code Documentation

Comments:

• Complex logic: Explained
• Public APIs: JSDoc documented
• Algorithms: Referenced (e.g., "Using minimax algorithm")

README:

• Setup instructions: Complete
• Running tests: Documented
• Build process: Clear
• Deployment: Detailed

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8.2 User Documentation

In-App Help:

• Rules of chess: Accessible
• How to play: Interactive tutorial
• Keyboard shortcuts: Listed

External Docs:

• User guide: Provided
• FAQ: Maintained
• Changelog: Updated

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9. Deployment Criteria

9.1 Pre-Deployment Checklist

• All tests pass (unit, integration, E2E)
• Code coverage meets thresholds
• Performance budgets met
• Accessibility audit passed
• Security scan clean
• Browser compatibility verified
• Documentation updated
• Changelog updated
• Release notes prepared

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9.2 Deployment Process

Staging Environment:

• Deploy to staging first
• Manual QA testing
• Stakeholder approval
• Soak test: 24 hours minimum

Production Deployment:

• Blue-green deployment
• Canary release: 5% traffic initially
• Monitor error rates
• Rollback plan: Ready

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10. Monitoring and Alerts

10.1 Production Metrics

Error Tracking:

• JavaScript errors: <0.1% of sessions
• Failed API calls: <1%
• Browser compatibility issues: <0.5%

Performance Monitoring:

• LCP degradation: Alert if >2.5s
• CLS increase: Alert if >0.1
• TTI slowdown: Alert if >4s

User Experience:

• Average game duration: Tracked
• Move frequency: Monitored
• Abandonment rate: <10%

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11. Success Metrics

11.1 Quality Score

Weighted Quality Score (0-100):

• Code coverage: 20 points
• Performance: 20 points
• Accessibility: 15 points
• Browser compatibility: 15 points
• Security: 15 points
• Test quality: 15 points

Minimum Acceptable Score: 85/100

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11.2 Release Readiness

Definition of Done:

1. Quality score ≥85
2. All critical bugs fixed
3. All acceptance tests passed
4. Documentation complete
5. Security scan passed
6. Performance benchmarks met
7. Accessibility audit passed
8. Stakeholder sign-off obtained

Go/No-Go Decision:

• Any criterion failed: No-go
• All criteria met: Approved for release
• Exceptions: Require VP approval

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12. Continuous Improvement

12.1 Retrospective Metrics

Track Over Time:

• Test coverage trends
• Performance trends
• Bug escape rate
• Time to fix defects

Quality Improvement:

• Quarterly review of thresholds
• Adjust based on team capability
• Benchmark against industry standards

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Appendix: Calculation Examples

Code Coverage Score

Coverage = (Statements + Branches + Functions + Lines) / 4
Example: (88 + 82 + 90 + 87) / 4 = 86.75%

Performance Score

Score = 100 - (LCP_penalty + CLS_penalty + TTI_penalty)
LCP_penalty = max(0, (LCP - 2.5) * 20)
Example: LCP=2.2s, CLS=0.05, TTI=3.0s → Score = 95

Quality Gate Pass/Fail

def quality_gate_passed(metrics):
    return (
        metrics.coverage >= 85 and
        metrics.performance_score >= 80 and
        metrics.accessibility_score >= 90 and
        metrics.security_vulnerabilities == 0 and
        metrics.critical_bugs == 0
    )