coverage-analyzer_skill

Overview

This skill analyzes test coverage to find untested files, prioritize what to test, and produce a practical improvement roadmap. It reports line, branch, and function coverage, highlights critical gaps, and ranks files by importance and effort. The goal is targeted, high-impact testing rather than chasing a raw percentage.

How this skill works

The skill reads coverage artifacts (lcov, coverage.json) when available or scans sources to estimate coverage and complexity. It categorizes files by importance (business logic, usage frequency, complexity) and computes priorities that combine coverage gap and impact. Outputs include untested file lists, low-coverage files, critical-code alerts, and a step-by-step improvement plan with estimated effort and expected gains.

When to use it

• You need a clear view of current coverage and coverage gaps
• You want to find untested or low-coverage files to prioritize tests
• Preparing a roadmap for improving coverage in a release or sprint
• Verifying that critical business logic is covered before deployment
• Estimating testing effort and expected coverage gains

Best practices

• Focus on business-critical and high-usage code before chasing 100% coverage
• Prioritize branch coverage for decision-heavy code paths
• Use complexity and import frequency to weight priorities, not just raw coverage
• Integrate coverage checks into CI to detect regressions early
• Combine this analysis with a test-quality review to avoid shallow tests

Example use cases

• Generate a ranked list of untested critical files (payments, auth) before a release
• Produce an improvement plan estimating hours to raise overall coverage to target levels
• Identify low-coverage components with high complexity for focused testing
• Validate that recently changed high-impact files have adequate tests
• Feed prioritized file list into a test-generator or assign to engineers in a sprint