socketdev updating-coverage
Runs the repo's coverage script and rewrites the README badge so the published number matches reality. Invoked directly via /update-coverage or as a phase of the updating umbrella.
When to use
- After landing a substantial change to test coverage (added a major feature with tests, removed a large untested module).
- Pre-release, to refresh the public badge.
- As part of
updatingumbrella flow when the repo declares a coverage script.
What it does NOT do
- Generate coverage from scratch. This skill consumes the output of the repo's existing coverage tooling (vitest / c8 / istanbul / node-test coverage). If no coverage script is declared in
package.json, the skill reports that and exits. - Compute coverage thresholds. The badge reflects what the tooling reports; tightening the threshold is a separate decision in the repo's vitest/c8 config.
- Modify nested READMEs. Only the repo-root
README.mdis rewritten. Nested READMEs underpackages/*have their own badges and lifecycles.
Phases
| # | Phase | Outcome |
|---|---|---|
| 1 | Discovery | Find the coverage script in package.json (cover / coverage / test:cover, in that preference). |
| 2 | Run | pnpm run <script>. Fail loudly if the run errors. |
| 3 | Rewrite | node scripts/fleet/gen/coverage-badge.mts — reads .cache/fleet/coverage/coverage-summary.json, rewrites the badge. |
| 4 | Commit | docs(readme): refresh coverage badge to N%. Direct-push per fleet norm. |
The parse + rewrite math (read the summary, round the percent, pick the color bucket, edit the README) is owned by scripts/fleet/gen/coverage-badge.mts and its lib scripts/fleet/lib/coverage-badge.mts — the same owner the commit-time gate scripts/fleet/check/coverage-badge-is-current.mts reads. This skill never re-derives the number or the format in shell; if it did, the badge it wrote (e.g. two decimals, a hard-coded color) would be rejected by check --all. The skill is orchestration over those scripts; the judgment it keeps is surfacing a real coverage-run failure.
Phase 1: discovery
node -e "import('./scripts/fleet/lib/coverage-badge.mts').then(m => { const s = m.coverageScriptName(process.cwd()); if (!s) { process.exit(1) } console.log(s) })"
coverageScriptName returns the first of cover / coverage / test:cover declared in package.json, or exits non-zero when the repo tracks no coverage. That is not a failure mode — many fleet repos don't track coverage; the skill exits cleanly.
Phase 2: run
pnpm run <SCRIPT>
Use the standard pnpm runner so the repo's own env config (catalog versions, etc.) applies. A real coverage-run failure is surfaced, not swallowed — that's the judgment this skill keeps.
Phase 3: rewrite
node scripts/fleet/gen/coverage-badge.mts
This reads .cache/fleet/coverage/coverage-summary.json (the json-summary reporter's output) and rewrites the README badge in place: the percent is Math.round-ed to an integer and the color is the bucket badgeColor computes (red → brightgreen). Exit 0 = written or already current; exit 1 = no coverage data / no badge to fill. To see the before value first, run node scripts/fleet/gen/coverage-badge.mts --check — the dry-run the gate uses — and read its output.
The canonical badge line in README.md is the placeholder a seeded repo ships:
The script fills <PCT> (and updates the color); the %25 is URL-encoded % and is left alone.
Phase 4: commit
git add README.md
git commit -m "docs(readme): refresh coverage badge to <N>%"
git push origin <default-branch>
Direct-push per the fleet's Commits & PRs → Push policy rule; fall back to PR if the remote rejects.
Output
When called via /update-coverage, emit a one-line summary of the integer percent before → after (read from the --check run). When no coverage script exists or the percentage is unchanged, exit silently.
Related
.claude/skills/updating/SKILL.md: umbrella that calls this skill when applicable..claude/skills/updating-security/SKILL.md: sibling underupdating.template/README.md: canonical README skeleton ships the placeholder badge.