test-gaps

name	test-gaps
description	Find files with low test coverage that have changed recently. Runs pytest or jest/vitest, cross-references with `git log --since`, and emits a Markdown report ranking 'no test touches it' first, 'coverage below threshold' second.
effort	low
argument-hint	[--threshold N] [--days N] [--repo PATH] [--no-run] [--out PATH]
allowed-tools	Read, Write, Edit, Bash, Glob, Grep
policy_doc_kind	skill
classification	canonical
canonical_owner	self
authority_level	procedural
in_verifier_scope	true

/test-gaps — Recent-Churn × Low-Coverage Cross-Reference

Find the highest-leverage gaps in your test suite: files that have changed in the last N days and either have no test coverage at all or fall below a threshold.

This is on-demand only. No cron, no daemon, no background worker. Run it when you want the answer.

Usage

/test-gaps                              # cwd, threshold 60%, last 7 days
/test-gaps --threshold 80 --days 14     # tighter bar, longer window
/test-gaps --repo ~/code/some-other-project  <!-- pointer-check:skip -->
/test-gaps --no-run                     # reuse last coverage report (skip pytest/jest run)

The skill writes a Markdown report to: ~/.claude/reports/test-gaps/{YYYY-MM-DD}-{repo-slug}.md

And prints a one-line summary on stdout.

Supported Runners (Day 1)

Runner	Detection	Coverage command
pytest	pyproject.toml [tool.pytest] / pytest.ini / conftest.py / any test_*.py	pytest --cov=. --cov-report=json:.test-gaps-coverage.json
jest / vitest	package.json declares jest or vitest, or jest/vitest config file	npx jest --coverage --coverageReporters=json-summary (or vitest run --coverage)

cargo / go test are deferred — add a runner branch in scripts/test_gaps.py if/when needed.

Workflow

1. Detect runner — scripts/detect_runner.sh returns pytest, jest, or unsupported. Bail on unsupported.
2. Run coverage — pytest --cov or npx jest --coverage, tolerating test failures (we want the coverage data even if tests fail).
3. Parse per-file coverage % — pytest coverage.json , or jest .