ISA-Frontend/.claude/commands/quality:coverage.md

/quality:coverage - Generate Test Coverage Report

Generate comprehensive test coverage report with recommendations for improving coverage.

Parameters

• library-name (optional): Specific library to analyze. If omitted, analyzes all libraries.

Tasks

1. Run Coverage Analysis

# Single library
npx nx test [library-name] --skip-nx-cache --coverage

# All libraries (if no library specified)
npm run ci # Runs all tests with coverage

2. Parse Coverage Report

Coverage output typically in:

• coverage/libs/[domain]/[layer]/[name]/
• Look for coverage-summary.json or text output

Extract metrics:

• Line coverage: % of executable lines tested
• Branch coverage: % of conditional branches tested
• Function coverage: % of functions called in tests
• Statement coverage: % of statements executed

3. Identify Uncovered Code

Parse coverage report to find:

• Uncovered files: Files with 0% coverage
• Partially covered files: < 80% coverage
• Uncovered lines: Specific line numbers not tested
• Uncovered branches: Conditional paths not tested

# List files with coverage below 80%
# (Parse from coverage JSON output)

4. Categorize Coverage Gaps

Critical (High Risk):

• Service methods handling business logic
• Data transformation functions
• Error handling code paths
• Security-related functions
• State management store actions

Important (Medium Risk):

• Component public methods
• Utility functions
• Validators
• Pipes and filters
• Guard functions

Low Priority:

• Getters/setters
• Simple property assignments
• Console logging
• Type definitions

5. Generate Recommendations

For each coverage gap, provide:

• File and line numbers
• Risk level (Critical/Important/Low)
• Suggested test type (unit/integration)
• Test approach (example test scenario)

Example:

📍 libs/oms/data-access/src/lib/services/order.service.ts:45-52
🔴 Critical - Business Logic
❌ 0% coverage - Error handling path

Recommended test:
it('should handle API error when fetching order', async () => {
  // Mock API to return error
  // Call method
  // Verify error handling
});

6. Calculate Coverage Trends

If historical data available:

• Compare with previous coverage percentage
• Show improvement/regression
• Identify files with declining coverage

7. Generate HTML Report

# Open coverage report in browser (if available)
open coverage/libs/[domain]/[layer]/[name]/index.html

8. Create Coverage Summary Report

Overall Metrics:

Coverage Summary for [library-name]
====================================

Line Coverage:     XX.X% (XXX/XXX lines)
Branch Coverage:   XX.X% (XXX/XXX branches)
Function Coverage: XX.X% (XXX/XXX functions)
Statement Coverage: XX.X% (XXX/XXX statements)

Target: 80% (Recommended minimum)
Status: ✅ Met / ⚠️ Below Target / 🔴 Critical

Files Needing Attention:

🔴 Critical (< 50% coverage):
  1. service-name.service.ts - 35% (business logic)
  2. data-processor.ts - 42% (transformations)

⚠️ Below Target (50-79% coverage):
  3. component-name.component.ts - 68%
  4. validator.ts - 72%

✅ Well Covered (≥ 80% coverage):
  - Other files maintaining good coverage

Top Priority Tests to Add:

1. [File:Line] - [Description] - [Risk Level]
2. ...

9. Framework-Specific Notes

Vitest:

• Coverage provider: v8 or istanbul
• Config in vitest.config.ts
• Coverage thresholds configurable

Jest:

• Coverage collected via --coverage flag
• Config in jest.config.ts
• Coverage directory: coverage/

10. Set Coverage Thresholds (Optional)

Suggest adding to test config:

// vitest.config.ts
coverage: {
  thresholds: {
    lines: 80,
    functions: 80,
    branches: 80,
    statements: 80
  }
}

Output Format

Test Coverage Report
====================

Library: [name]
Test Framework: [Vitest/Jest]
Generated: [timestamp]

📊 Coverage Metrics
-------------------
Lines:      XX.X% ████████░░ (XXX/XXX)
Branches:   XX.X% ███████░░░ (XXX/XXX)
Functions:  XX.X% █████████░ (XXX/XXX)
Statements: XX.X% ████████░░ (XXX/XXX)

🎯 Target: 80% | Status: [✅/⚠️/🔴]

🔍 Coverage Gaps
----------------
[Categorized list with priorities]

💡 Recommendations
------------------
[Prioritized list of tests to add]

📈 Next Steps
-------------
1. Focus on critical coverage gaps first
2. Add tests for business logic in [files]
3. Consider setting coverage thresholds
4. Re-run: npx nx test [library-name] --skip-nx-cache --coverage

Error Handling

• No coverage data: Ensure --coverage flag used
• Missing library: Verify library name is correct
• Coverage tool not configured: Check test config for coverage setup

References

• docs/guidelines/testing.md
• CLAUDE.md Testing Framework section
• Vitest coverage: https://vitest.dev/guide/coverage
• Jest coverage: https://jestjs.io/docs/configuration#collectcoverage-boolean