test(spec-tooling): restore the liveness author-lint's array fan-out assertion (#7079)

[os-help]

Fixes #7079

What was lost, and what pays it back

getNested (packages/lint/src/lint-liveness-properties.ts:146) resolves a dotted warn-map path by fanning it out over an array container level — navigation.runAction must check every navigation entry, not just navigation[0]. That reach is the half a walk can lose silently: a getNested that stopped at index 0 still warns on every single-entry fixture, on every top-level warned key, and on the first item of every real app, so nothing else in the suite goes red.

It had exactly one subject, dashboard.widgets.colorVariant, and #6774 flipped that row to live. The assertion — "fans out over EVERY widget, not just the first" — was removed with a tombstone comment rather than downgraded into a silence check that would pass on a broken fan-out. #7079 recorded the loss.

app.props.navigation.children.runAction is now a dotted warned path under an array container: #4848's spec half, planned + authorWarn (the declared deep-link auto-run slot is validated at authoring, but no shipped shell reads it yet), and navigation is an array in all three authored apps. The assertion is rebuilt against it in the deleted test's construction — the warned key on navigation[1], nowhere on navigation[0].

The evidence is the mutation, not the green suite

A test that merely passes today would be the exact non-test this card was filed to avoid. So getNested was temporarily broken to take only c[0] at an array level:

 ❯ src/lint-liveness-properties.test.ts (32 tests | 1 failed) 120ms
       × fans out over EVERY navigation entry, not just the first 12ms

AssertionError: expected [] to have a length of 1 but got +0
 ❯ src/lint-liveness-properties.test.ts:572:23

 Test Files  1 failed | 69 passed (70)
      Tests  1 failed | 1883 passed (1884)

The new assertion is the only failure in the entire package — the red is attributable to the broken walk, not to collateral damage. Mutation reverted, getNested byte-identical to main:

 Test Files  70 passed (70)
      Tests  1884 passed (1884)

Also in the block

• a control pinning that index 0 is not a blind spot either, so a red on the main assertion reads "the fan-out is broken", not "the walk moved";
• the checkItem one-finding-per-(item, path) contract the toHaveLength(1) rests on, so that number is pinned rather than accidental;
• a silence pin for navigation entries authoring no warned key;
• the tombstone comment at :448 replaced by a pointer to this resolution.

Because the discriminating assertion is a positive warning, it cannot pass vacuously: lintLivenessProperties returns [] both when the ledgers fail to load and when the walk is broken, and this block fails in either case.

Option 1 (export getNested) — declined, deliberately

The card offered a ledger-independent unit test via an exported getNested or an @internal seam, and named its cost: a second contract on a function whose entire design is "ledger-driven, coverage grows by marking entries". Declined, because the mutation above shows the ledger-driven test already delivers the one fact the card asks for — it distinguishes a working walk from one that never looks past [0]. A seam would add public surface to @objectstack/lint for no additional discriminating power, and would cost the property this test has and a unit test would not: it holds the real shipped ledger to its authorWarn on that row, the contract this file's header docblock describes.

Scope

Entirely packages/lint/src/lint-liveness-properties.test.ts (+99 / −9, one file). No ledger row was added or flipped — the subject already existed. lint-liveness-properties.ts, packages/spec/liveness/*.json, packages/spec/src/**/*.zod.ts and content/docs/releases/** are untouched.

Gates

Gate	Invocation	Result
tests	pnpm --filter @objectstack/lint run test	1884 passed (70 files)
typecheck	pnpm --filter @objectstack/lint run typecheck	clean

skip-changeset: test-only, nothing published changes — packages/lint's files ships dist, README.md, CHANGELOG.md, and vitest sources are in none of them. AGENTS.md:1018 requires a changeset for feature work; the label's own description is "PR has no user-facing published change; bypasses the changeset gate". Precedent: #7579 (test(drivers): remove redundant object: key from mongodb/sql query test literals), merged test-only with the label.

---

Generated by Claude Code

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
objectstack	Ignored		Aug 11, 2026 10:17am

[github-actions]

📓 Docs Drift Check

No hand-written docs reference the 0 changed package(s). ✅