Skill Detail

Gate Diff Only Test Coverage On Changed Lines Before Merging With Diff Cover

Compare coverage reports against a git diff so an agent can flag newly changed lines that still lack tests before merge.

Code Quality & ReviewMulti-Framework
Code Quality & Review Multi-Framework Security Reviewed
โญ 828 GitHub stars
INSTALL WITH ANY AGENT
npx skills add agentskillexchange/skills --skill gate-diff-only-test-coverage-on-changed-lines-before-merging-with-diff-cover Copy
Works best when you want a reusable capability, not another fragile one-off prompt.
At a glance
Tools required
Git, supported XML or LCov coverage report, Python 3, pip
Install & setup
pip install diff-cover
Author
Matthias Bachmann and contributors
Publisher
Open Source
Last updated
Apr 17, 2026
Quick brief

diff-cover is a focused review-gate skill for checking whether newly changed lines are covered by tests, rather than judging whole-repository coverage. An agent should invoke it when a pull request needs a fast diff-only coverage decision before merge, especially in CI or review workflows where full coverage percentages hide risk on changed code.

How it works

What this skill actually does

Use this instead of a general coverage dashboard when the real question is, ‘Did the lines we just changed get covered?’ The boundary is precise: compare git diff output against Cobertura, Clover, JaCoCo, or LCov coverage reports and emit a patch-scoped result. It is not a general testing framework or product listing.