Test Coverage Analyzer Skill

Analyzes test coverage comprehensively to identify gaps and ensure adequate test safety nets before undertaking migration efforts.

Purpose

Enable comprehensive test coverage analysis for:

• Pre-migration coverage assessment
• Critical path coverage verification
• Coverage gap identification
• Test strategy planning
• Regression risk assessment

Capabilities

1. Line/Branch/Path Coverage Measurement

• Calculate line coverage percentages
• Measure branch coverage
• Analyze path coverage
• Track condition coverage

2. Coverage Gap Identification

• Find untested code paths
• Identify missing edge cases
• Detect uncovered error handlers
• Map coverage blind spots

3. Critical Path Coverage Analysis

• Identify business-critical paths
• Prioritize coverage by importance
• Map risk vs coverage
• Generate focused test recommendations

4. Integration Test Coverage Mapping

• Track integration point coverage
• Map API endpoint testing
• Assess database operation coverage
• Verify external service testing

5. Coverage Trend Analysis

• Track coverage over time
• Identify coverage regression
• Monitor improvement progress
• Generate trend reports

Tool Integrations

Tool	Language	Integration Method
Istanbul/nyc	JavaScript/TypeScript	CLI
JaCoCo	Java	CLI / Maven/Gradle
Cobertura	Java/Python	CLI
Coverage.py	Python	CLI
SimpleCov	Ruby	CLI
go test -cover	Go	CLI
dotCover	.NET	CLI

Output Schema

{
  "analysisId": "string",
  "timestamp": "ISO8601",
  "coverage": {
    "line": {
      "percentage": "number",
      "covered": "number",
      "total": "number"
    },
    "branch": {
      "percentage": "number",
      "covered": "number",
      "total": "number"
    },
    "function": {
      "percentage": "number",
      "covered": "number",
      "total": "number"
    }
  },
  "gaps": [
    {
      "file": "string",
      "uncoveredLines": ["number"],
      "uncoveredBranches": ["string"],
      "criticality": "high|medium|low",
      "recommendation": "string"
    }
  ],
  "criticalPaths": {
    "covered": "number",
    "total": "number",
    "uncoveredPaths": []
  }
}

Integration with Migration Processes

• migration-testing-strategy: Coverage baseline establishment
• code-refactoring: Pre-refactoring safety assessment
• framework-upgrade: Regression protection verification

Related Skills

• characterization-test-generator: Generate tests for gaps
• static-code-analyzer: Combined quality analysis

Related Agents

• migration-testing-strategist: Uses for test planning
• regression-detector: Uses for regression prevention