🧪 Add branch coverage tests for constants files (currently 0% branch coverage)

[pethers]

🤖 Recommended Agent: @testing-agent

This issue is best handled by the Testing Agent - an expert in test coverage improvement and branch testing.

🎯 Objective

Add comprehensive branch coverage tests for constants files to ensure conditional logic is properly tested and achieve 70%+ branch coverage for v1.0 release.

📋 Background

Many constant files in src/constants/ have 0% branch coverage despite containing conditional logic, type guards, and data transformations. This creates risk of untested code paths and reduces overall branch coverage below the 70% ISMS requirement.

📊 Current State (Measured Metrics)

Constants Files with 0% or Low Branch Coverage:

• src/constants/appConstants.ts: 90.24% statements / 0% branches
• src/constants/businessConstants.ts: 53.33% statements / 0% branches
• src/constants/costConstants.ts: 80% statements / 0% branches
• src/constants/riskConstants.ts: 86.66% statements / 0% branches
• src/constants/securityLevels.ts: 72.72% statements / 0% branches
• src/constants/testIds.ts: 81.66% statements / 0% branches (64.51% functions)
• src/constants/uiConstants.ts: 50% statements / 16.66% branches

Overall Impact:

• Current branch coverage: 64.9%
• Target branch coverage: 70%
• Gap: 5.1% - constants contribute significantly to this gap

✅ Acceptance Criteria

• All constants files have ≥70% branch coverage
• Test files created for each constants file with conditional logic
• All conditional branches tested (if/else, ternary operators, switch statements)
• All exported helper functions tested with edge cases
• Overall project branch coverage ≥70%
• All tests follow Vitest + existing test patterns

🛠️ Implementation Guidance for @testing-agent

Test Files to Create:

1. src/constants/appConstants.test.ts - Test app configuration logic
2. src/constants/businessConstants.test.ts - Test business logic constants
3. src/constants/costConstants.test.ts - Test cost calculation constants
4. src/constants/riskConstants.test.ts - Test risk assessment logic
5. src/constants/securityLevels.test.ts - Test security level mappings
6. src/constants/uiConstants.test.ts - Test UI configuration branches
7. src/constants/testIds.test.ts - Test ID generation functions

Agent-Specific Testing Strategy:

✅ Use Vitest for all constant file tests
✅ Follow Arrange-Act-Assert pattern
✅ Test all conditional branches: if/else, ternary operators, switch statements
✅ Test helper functions with edge cases (null, undefined, empty strings)
✅ Test type guards and validation functions
✅ Use descriptive test names that explain what is being tested

Example Test Pattern:

// src/constants/securityLevels.test.ts
import { describe, it, expect } from 'vitest';
import { 
  SECURITY_LEVELS, 
  getSecurityLevelName, 
  isValidSecurityLevel 
} from './securityLevels';

describe('securityLevels', () => {
  describe('SECURITY_LEVELS constant', () => {
    it('contains all required levels', () => {
      expect(SECURITY_LEVELS).toContain('None');
      expect(SECURITY_LEVELS).toContain('Low');
      expect(SECURITY_LEVELS).toContain('Moderate');
      expect(SECURITY_LEVELS).toContain('High');
      expect(SECURITY_LEVELS).toContain('Very High');
    });
  });

  describe('getSecurityLevelName', () => {
    it('returns correct name for each level', () => {
      expect(getSecurityLevelName('None')).toBe('No Security');
      expect(getSecurityLevelName('Low')).toBe('Basic Security');
      expect(getSecurityLevelName('High')).toBe('Advanced Security');
    });

    it('handles invalid levels', () => {
      expect(getSecurityLevelName('invalid')).toBe('Unknown');
    });

    it('handles edge cases', () => {
      expect(getSecurityLevelName(null as any)).toBe('Unknown');
      expect(getSecurityLevelName(undefined as any)).toBe('Unknown');
      expect(getSecurityLevelName('')).toBe('Unknown');
    });
  });

  describe('isValidSecurityLevel', () => {
    it('returns true for valid levels', () => {
      SECURITY_LEVELS.forEach(level => {
        expect(isValidSecurityLevel(level)).toBe(true);
      });
    });

    it('returns false for invalid levels', () => {
      expect(isValidSecurityLevel('invalid')).toBe(false);
      expect(isValidSecurityLevel('')).toBe(false);
      expect(isValidSecurityLevel(null as any)).toBe(false);
    });
  });
});

Testing Patterns by File:

appConstants.ts:

• Test environment-specific configurations
• Test feature flag logic
• Test version and build metadata

businessConstants.ts:

• Test business rules with different inputs
• Test calculation thresholds and limits
• Test data classification logic

costConstants.ts:

• Test cost tier logic (small, medium, large)
• Test percentage calculations
• Test currency formatting functions

riskConstants.ts:

• Test risk level classification
• Test risk score calculations
• Test risk categorization logic

testIds.ts:

• Test ID generation for different component types
• Test ID sanitization logic
• Test edge cases (empty strings, special characters)

Verification Commands:

# Run tests for constants
npm test -- src/constants

# Check coverage for specific file
npm run coverage -- src/constants/securityLevels.ts

# Run all tests with coverage
npm run coverage

🔗 Related Resources

• ISMS Secure Development Policy - 70% branch coverage requirement
• Vitest Testing Guide
• Testing Agent Documentation
• Existing test patterns: src/services/*.test.ts

📊 Metadata

Agent: @testing-agent | Priority: Medium | Effort: S (3-4h)
Labels: type:test, domain:testing, priority:medium, size:small, v1.0