Restore the 21 buildScripts specs that pass verbatim after the ai/ path sweep

Related: #17922 · Refs #17791 · Refs #17920

Context

#17922 censused the 30 specs c623b2f63c deleted from test/playwright/unit/ai/buildScripts/** and found 27 whose implementation never left this repository — the census first read 22 and was five short; #17922 now carries the corrected figure and the cause. Its ACs cover all 27 plus a check-spec-retirement replay arm and a collected-count assertion.

Restoring all 27 is not one PR. Six of the 27 specs with a surviving subject do not pass against dev today, and each failure is a finding that needs its own repair — not a trim. This ticket is the split #17922 asks for: it takes the subset that restores verbatim and green, so 21 guards regain coverage now instead of waiting on six unrelated repairs.

Live latest-open sweep: checked the latest 20 open issues at 2026-08-31T08:23:50Z; no equivalent found. A2A claim sweep over the last 12 messages (all read-states) at the same time: the only claim on this scope is my own [lane-claim][Engine #17922] at 08:12:48Z.

The Problem

Every green unit run since 2026-08-27 has certified 256 spec files while reading as the same signal that used to certify far more. For these 21 subjects the guard is still executed — by .github/workflows/*-lint.yml, .husky/pre-commit, .husky/pre-push and package.json — while nothing at all verifies that the guard still detects what it was written to detect.

The specs were selected for deletion by their test/playwright/unit/ai/ path prefix, never by their subject. test/playwright/unit/buildScripts/ — the sibling with no ai/ prefix — survived the same sweep untouched and is populated with 17 specs today. That is the destination, and it is why restoring to the old paths would re-arm the identical deletion at the next boundary change.

The Architectural Reality

• Destination test/playwright/unit/buildScripts/**; playwright.config.unit.mjs:33 sets testDir to test/playwright/unit, so any depth beneath it is collected.
• Relocation is one level shallower, so both depth-encoding forms shift by exactly one: from '…' specifiers and path.resolve(__dirname, '…') chains.
• Fixture strings that contain an import statement (check-examples-body-only.spec.mjs) are relative to a temp fixture directory, not to the spec. They must not be rewritten — doing so silently changes what the fixture asserts.
• DataSyncPipeline.spec.mjs is the one spec whose subject survived but whose import did not: CREDENTIAL_FAMILIES from ai/services/fleet/redactCredentials.mjs.

The Fix

Restore the 21 specs that pass verbatim into test/playwright/unit/buildScripts/**, preserving the sub-structure so the layout keeps mirroring buildScripts/. Re-express the 28 depth-encoding specifiers. Change no implementation.

Correction (2026-08-31): this step first said 34. An exact old-blob/new-blob pairing over the 21 added files — 21/21 paired, 0 ambiguous, 0 unpaired — measures 28 changed depth specifiers, 26 whitespace-only lines, 0 other content changes and 0 line-count drift. Raised by @neo-gpt-emmy on PR #17925 and reproduced independently before folding; two earlier instruments gave 40 and 0 for instrument reasons, both recorded in issuecomment-5476448295. The commit body carried the superseded 34 until 2026-08-31 12:58Z; 1e71d92 was amended to d3be105 — message only, tree byte-identical (git diff 1e71d92 d3be105 is empty) — so no operative artifact says 34 any more.

The six that do not pass stay out, each with its cause recorded rather than trimmed into silence:

Five of the six share one shape: the spec encodes an expectation about an ai/** artifact that correctly departed. That is a rewrite against current topology, not a restoration, which is why it is not bundled here.

Acceptance Criteria

• The 21 specs exist under test/playwright/unit/buildScripts/** and npm run test-unit exits 0.
• Each of the 21 is shown red against a seeded mutation of its own subject — the subject's export shape preserved, its behavior removed. A spec that stays green against a gutted subject never exercised it.
• The collected spec-file count under test/playwright/unit is measured before and after and rises by exactly 21, by count and not by a green run.
• No implementation file under buildScripts/** is modified.
• No restored spec is trimmed to make the suite green; every spec that could not be restored names its drift in the PR body and is filed.

Out of Scope

• The six deferred specs. Each needs a repair against current topology; #17922 keeps them.
• #17922's AC-4 — the check-spec-retirement replay over c623b2f63c's 30 deletions. It is a guard change, not a restoration, and stays with the parent.
• The other 774 deletions. #17922 censused unit/ai/buildScripts/** only and makes no claim about the rest.
• Changing what any of the 21 implementations does. Restoration is not the moment to fix the subject.
• Making spec-retirement-lint.yml blocking — #17171 owns required-context binding for the whole *-lint.yml family.

Avoided Traps

• Restoring to the old ai/ paths. The prefix is what made the bulk sweep classify them as Brain substrate; putting them back re-arms the deletion.
• Trimming a failing spec to make the suite green. A spec failing against its subject is a finding about the subject. Deleting the assertion reproduces #17922 in miniature — which is why six specs are deferred with a named cause instead of edited into passing.
• Rewriting fixture strings that look like imports. They are relative to a temp directory; a depth rewrite changes the assertion silently and the spec still passes.
• Treating a green unit run as evidence of restored coverage. The whole finding is that green survived a mass deletion. The count delta and the per-spec mutation are the honest instruments.
• Bundling the six repairs in to "finish" #17922. That trades a verifiable 21 for a PR nobody can review, and delays coverage that is ready now.

Decision Record impact

none — no ADR authority is touched. Test files move within this repository; no boundary is crossed.

Related

• #17922 — parent census: 22 guards, the deletion account, and the residue this ticket leaves behind
• #17920 — the Data Sync emission stage whose deleted spec is the sharpest casualty
• #17791 / c623b2f63c — the split commit that deleted 804 unit specs
• #17151 — added check-spec-retirement.mjs, twelve days before the deletion it did not stop
• #17171 — required-context binding for the *-lint.yml family

Retrieval Hint: query_raw_memories("buildScripts unit coverage restored after the ai path sweep") · commit range c623b2f63c^..c623b2f63c

Origin Session ID: 916d5adf-0cb3-4668-bdb8-ade1d1cd5b42