Charon/docs/plans/archive/codecov_config_analysis.md

Codecov Configuration Analysis & Recommendations

Date: December 14, 2025 Issue: Local coverage (85.1%) vs Codecov dashboard (Backend 81.05%, Frontend 81.79%, Overall 81.23%)

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1. Current Ignore Configuration Analysis

Current .codecov.yml Ignore Patterns

The existing configuration at .codecov.yml already has a comprehensive ignore list:

Category	Patterns	Status
Test files	**/tests/**, **/test/**, **/__tests__/**, **/*_test.go, **/*.test.ts, **/*.test.tsx, **/*.spec.ts, **/*.spec.tsx	✅ Good
Vitest config	**/vitest.config.ts, **/vitest.setup.ts	✅ Good
E2E/Integration	**/e2e/**, **/integration/**	✅ Good
Documentation	docs/**, *.md	✅ Good
CI/Config	.github/**, scripts/**, tools/**, *.yml, *.yaml, *.json	✅ Good
Frontend artifacts	frontend/node_modules/**, frontend/dist/**, frontend/coverage/**, frontend/test-results/**, frontend/public/**	✅ Good
Backend artifacts	backend/cmd/seed/**, backend/data/**, backend/coverage/**, backend/bin/**, backend/*.cover, backend/*.out, backend/*.html, backend/codeql-db/**	✅ Good
Docker-only code	backend/internal/services/docker_service.go, backend/internal/api/handlers/docker_handler.go	✅ Good
CodeQL artifacts	codeql-db/**, codeql-db-*/**, codeql-agent-results/**, codeql-custom-queries-*/**, *.sarif	✅ Good
Config files	**/tailwind.config.js, **/postcss.config.js, **/eslint.config.js, **/vite.config.ts, **/tsconfig*.json	✅ Good
Type definitions	**/*.d.ts	✅ Good
Data directories	import/**, data/**, .cache/**, configs/crowdsec/**	✅ Good

Coverage Discrepancy Root Cause

The ~4% difference between local (85.1%) and Codecov (81.23%) is likely due to:

1. Local script exclusions not in Codecov: The scripts/go-test-coverage.sh excludes packages via sed filtering:

   • github.com/Wikid82/charon/backend/cmd/api
   • github.com/Wikid82/charon/backend/cmd/seed
   • github.com/Wikid82/charon/backend/internal/logger
   • github.com/Wikid82/charon/backend/internal/metrics
   • github.com/Wikid82/charon/backend/internal/trace
   • github.com/Wikid82/charon/backend/integration

2. Frontend test utilities counted as source: Several test utility directories/files may be included:

   • frontend/src/test/ - Test setup files
   • frontend/src/test-utils/ - Test helper utilities
   • frontend/src/testUtils/ - Additional test helpers
   • frontend/src/data/mockData.ts (already in vitest.config.ts excludes but not in Codecov)

3. Entry point files: Main bootstrap files with minimal testable logic:

   • backend/cmd/api/main.go - App bootstrap
   • frontend/src/main.tsx - React entry point

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2. Recommended Additions

High Priority (Align with Local Coverage)

Pattern	Rationale	Impact
backend/cmd/api/**	Main entry point - bootstrap code, CLI handling	~1-2%
backend/internal/logger/**	Logging infrastructure - already excluded locally	~0.5%
backend/internal/metrics/**	Observability infrastructure	~0.5%
backend/internal/trace/**	Tracing infrastructure	~0.3%

Medium Priority (Test Infrastructure)

Pattern	Rationale	Impact
frontend/src/test/**	Test setup files (setup.ts, setup.spec.ts)	~0.3%
frontend/src/test-utils/**	Query client helpers for tests	~0.2%
frontend/src/testUtils/**	Mock proxy host creators	~0.2%
**/mockData.ts	Test data factories	~0.2%
**/createTestQueryClient.ts	Test-specific utilities	~0.1%
**/createMockProxyHost.ts	Test-specific utilities	~0.1%
frontend/src/main.tsx	React bootstrap - no logic to test	~0.1%

Low Priority (Already Partially Covered)

Pattern	Rationale	Impact
**/playwright.config.ts	E2E configuration	Minimal
backend/tools/**	Build scripts (tools/ already ignored)	Already covered

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3. Exact YAML Changes for .codecov.yml

Add the following patterns to the ignore: section:

# -----------------------------------------------------------------------------
# Exclude from coverage reporting
# -----------------------------------------------------------------------------
ignore:
  # Test files
  - "**/tests/**"
  - "**/test/**"
  - "**/__tests__/**"
  - "**/test_*.go"
  - "**/*_test.go"
  - "**/*.test.ts"
  - "**/*.test.tsx"
  - "**/*.spec.ts"
  - "**/*.spec.tsx"
  - "**/vitest.config.ts"
  - "**/vitest.setup.ts"

  # E2E tests
  - "**/e2e/**"
  - "**/integration/**"

  # === NEW: Frontend test utilities ===
  - "frontend/src/test/**"
  - "frontend/src/test-utils/**"
  - "frontend/src/testUtils/**"
  - "**/mockData.ts"
  - "**/createTestQueryClient.ts"
  - "**/createMockProxyHost.ts"

  # === NEW: Entry points (bootstrap code, minimal logic) ===
  - "backend/cmd/api/**"
  - "frontend/src/main.tsx"

  # === NEW: Infrastructure packages (align with local coverage script) ===
  - "backend/internal/logger/**"
  - "backend/internal/metrics/**"
  - "backend/internal/trace/**"

  # Documentation
  - "docs/**"
  - "*.md"

  # CI/CD & Config
  - ".github/**"
  - "scripts/**"
  - "tools/**"
  - "*.yml"
  - "*.yaml"
  - "*.json"

  # Frontend build artifacts & dependencies
  - "frontend/node_modules/**"
  - "frontend/dist/**"
  - "frontend/coverage/**"
  - "frontend/test-results/**"
  - "frontend/public/**"

  # Backend non-source files
  - "backend/cmd/seed/**"
  - "backend/data/**"
  - "backend/coverage/**"
  - "backend/bin/**"
  - "backend/*.cover"
  - "backend/*.out"
  - "backend/*.html"
  - "backend/codeql-db/**"

  # Docker-only code (not testable in CI)
  - "backend/internal/services/docker_service.go"
  - "backend/internal/api/handlers/docker_handler.go"

  # CodeQL artifacts
  - "codeql-db/**"
  - "codeql-db-*/**"
  - "codeql-agent-results/**"
  - "codeql-custom-queries-*/**"
  - "*.sarif"

  # Config files (no logic)
  - "**/tailwind.config.js"
  - "**/postcss.config.js"
  - "**/eslint.config.js"
  - "**/vite.config.ts"
  - "**/tsconfig*.json"
  - "**/playwright.config.ts"

  # Type definitions only
  - "**/*.d.ts"

  # Import/data directories
  - "import/**"
  - "data/**"
  - ".cache/**"

  # CrowdSec config files (no logic to test)
  - "configs/crowdsec/**"

---

4. Summary of New Patterns

Patterns to Add (12 new entries)

# Frontend test utilities
- "frontend/src/test/**"
- "frontend/src/test-utils/**"
- "frontend/src/testUtils/**"
- "**/mockData.ts"
- "**/createTestQueryClient.ts"
- "**/createMockProxyHost.ts"

# Entry points
- "backend/cmd/api/**"
- "frontend/src/main.tsx"

# Infrastructure packages
- "backend/internal/logger/**"
- "backend/internal/metrics/**"
- "backend/internal/trace/**"

# Additional config
- "**/playwright.config.ts"

Expected Impact

After applying these changes:

• Backend Codecov: Should increase from 81.05% → ~84-85%
• Frontend Codecov: Should increase from 81.79% → ~84-85%
• Overall Codecov: Should increase from 81.23% → ~84-85%

This will align Codecov reporting with local coverage calculations by ensuring the same exclusions are applied in both environments.

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5. Validation Steps

1. Apply the YAML changes to .codecov.yml
2. Push to trigger CI workflow
3. Compare new Codecov dashboard percentages with local scripts/go-test-coverage.sh output
4. If still misaligned, check for additional patterns in vitest.config.ts coverage.exclude not in Codecov

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6. Alternative Consideration

If exact parity isn't achieved, consider that:

• Codecov may calculate coverage differently (line vs statement vs branch)
• Go coverage profiles include function coverage that may be weighted differently
• The local script uses sed filtering on the raw coverage file, which Codecov cannot replicate

The ignore patterns above address files that should never be counted regardless of methodology differences.