# WP-46 — Vitest coverage (report + thresholds)

Status: done
Phase: 8 — platform/DX/showcase
Priority: P1

## Outcome

Coverage is first-class in the `@angular/build:unit-test` builder — no separate vitest config
needed. Added a `coverage` **configuration** to the `test` target in `angular.json` (`coverage: true`,
reporters `text-summary`/`html`/`lcov`, excludes for specs/stories/contracts/generated
`api-client.ts`/`main.ts`/`.d.ts`) + `@vitest/coverage-v8` (pinned to vitest's 4.1.9 to avoid the
mixed-version warning). `npm run test:coverage` → `ng test --configuration coverage`. **Report-only
(no thresholds)** per the ponytail default — visibility first. CI's test step now runs
`test:coverage` (a strict superset of `npm test`: fails on a failing test, never on coverage).
Baseline at delivery: **~71% statements / 69% branches / 68% functions / 74% lines.** Output dir
`coverage/` was already git-ignored. Path to enforce later: add `coverageThresholds` to the config.

## Why

Tests run via the `@angular/build:unit-test` (Vitest) builder but report no coverage — there's no
visibility into what the house test rules actually cover. A template/showcase should surface this.

## Decisions

- **Step 1 — verify wiring:** confirm how coverage is enabled with the Angular unit-test builder
  (`codeCoverage` option and/or a vitest config), add `@vitest/coverage-v8`.
- `npm run test:coverage` → text + HTML/lcov report.
- **Report-only first** (ponytail: visibility before a blocking gate, like the semgrep job).
  Threshold focus on the layers the house rules already demand tests for (`domain/**`, pure
  combinators, `parse*` boundaries, reducers), not a blanket global %; exclude stories, the
  generated `api-client.ts`, and DTOs/contracts.
- Wire into `ci-local.sh`/CI **non-blocking**, with a documented path to flip on enforcement later.
- **Open choice:** report-only vs enforce a minimum now.

## Files

- `package.json` (`test:coverage` + dep), coverage config (builder option or vitest config).
- `scripts/ci-local.sh` / `.github/workflows/ci.yml` — non-blocking coverage step.
- `.gitignore` — ignore the coverage output dir.

## Acceptance criteria

- [x] `npm run test:coverage` produces a report (text-summary + HTML/lcov) with sensible excludes.
- [x] Coverage runs in CI without failing the build (report-only).
- [x] `npm run ci` green.