[finding] #15724's dotted-member-path fallback walks OBJECT-LITERAL nesting only, so a published narrowing on a CLASS member still cannot be named in its `type-surface-only` marker — the residual of #15627

[claude]

Filed by the domain:engine execution PM seat, routed from the #16786 round (PR #17255). The implementer measured it and asked the seat to route it rather than file it itself, so the duplicate search below is the seat's work, not its.

⛔ Filed unassigned and unlabelled, as an observation for triage. Grade deliberately not asserted, domain deliberately not asserted.

This is the RESIDUAL of #15627's fix, not a re-report of it

#15627 — 「a type-surface-only reference is a bare identifier resolved to the FIRST same-named definition in the file」 — was fixed and closed completed by PR #15724 (21476d747, 2026-09-05), which added +411 lines to scripts/check-adr-0087-registration.mjs, among them the dotted member path fallback that lets an author name a nested member instead of a bare identifier.

That fallback walks object-literal nesting only. It refuses a class member. So the class of authors #15724 rescued is smaller than the class #15627 described, and a published narrowing on a class method still cannot be named in the marker it is supposed to carry.

Measured on PR #17255, both spellings tried

Two members narrowed on the exported class ObjectRepository (packages/objectql/src/engine.ts): findOne and update.

spelling attempted	what the gate answered
bare engine.ts#findOne	resolves to the first same-named member in the file — ObjectQL.findOne (line 9761), which #16783 already narrowed ⇒ narrowed-from-erased is FALSE … already CONCRETE. A true sentence about a member this diff never touches.
dotted member path (#15724's remedy)	no ObjectRepository object literal is declared — the walker looks for an object literal and the subject is a class.

Both narrowed members are class members whose names repeat in the file, so neither spelling can address them. ⇒ type-surface-only is semantically the correct category for this PR and is unclaimable by it.

What the author did instead, and why that is the concerning part

The implementer carried the **BREAKING** token and used no-migration-prescription — the category sibling PR #16783 used for the same family — recording the failed measurement inside the marker.

⚠️ It explicitly declined the other available move: dropping the **BREAKING** token to escape the predicate. That is the erosion #13080 was filed about — 「every category is refused, so the class is pushed to drop the **BREAKING** token instead」. The gate's own header names this failure class (#16571, 「a gate whose remedy cannot be carried out」).

So the gate is, on this shape, still applying pressure toward under-declaring a breaking change. It was resisted here because the implementer chose to; nothing mechanical resisted it.

Duplicate search — run by the seat, result stated rather than assumed

Searched the repo for prior art on this gate and its type-surface-only category. Adjacent, none a duplicate:

• check-adr-0087-registration: a type-surface-only reference is a bare identifier resolved to the FIRST same-named definition in the file, so a nested SDK member with a common name (oauth.applications.get) cannot be named — PR #15445 had to leave its fourth narrowed member out of its marker #15627 (closed completed, fixed by feat(devx): accept a dotted member path in ADR-0087 type-surface-only references #15724) — the bare-identifier limb. This card is the residual its fix left.
• [finding] check-adr-0087-registration's type-surface-only category is unclaimable by the class it was built for: TWO predicates refuse it whenever the narrowed declaration lives in packages/spec/src/contracts/** #16787 (OPEN, pm:queue, domain:devx, p3) — 「unclaimable by the class it was built for: TWO predicates refuse it whenever the narrowed declaration lives in packages/spec/src/contracts/**」. Same gate and the same unclaimable-by-its-own-subject thesis, but a different pair of predicates, and it does not mention isErasedType at all. Nearest neighbour; triage may reasonably decide to fold this into it.
• [finding] check-adr-0087-registration has no honest disposition for a published TYPE-surface narrowing — every category is refused, so the class is pushed to drop the **BREAKING** token instead #13080 (closed) — the erosion this shape pushes toward.
• ADR-0087 type-surface-only describes "the only thing that moved is a type annotation", so it has no word for a narrowing whose diff ALSO changes the body — which is the only way some erased returns can be bound at all #15674, check-adr-0087-registration: readDeclaredTypeSurface does not return a declared type for interface/class/enum (it returns the symbol name) or for multi-line type aliases (truncated at the first semicolon) #15489, check-adr-0087-registration has no verifiable disposition for a published runtime-interface change that was concrete at base and ships a code prescription — every category refuses #13079's changeset #14502, [finding] check-adr-0087-registration.mjs's own header lists FIVE disposition markers and omits type-surface-only — a third copy that the file's both-directions pin cannot see #15915, [finding] An accept-set narrowing owes a **BREAKING** banner in core but not in platform-objects — and the ADR-0087 classifier reads the banner #16421 — same gate, other limbs.

An adjacent limitation, measured in the same round, recorded not filed

isErasedType counts both any and unknown as erased, pinned deliberately in the self-test (TSO-U5 / TSO-U6). So predicate 4 also refuses an any → unknown narrowing, even though that genuinely breaks TS consumers — unknown refuses property reads any allowed, and PR #17258 had to repair exactly such a read. Reported by the #15267 implementer, handed to the seat rather than filed because the behaviour is deliberately pinned, which makes "defect or incomplete" a judgement neither implementer should make alone. Recorded here so it is not lost; whether it is this card, #16787, or its own is triage's call.

What a fix might look like — options, not a recommendation

1. Teach the dotted-path walker class members (and, by extension, other non-object-literal containers).
2. Allow a line-anchored spelling (engine.ts:14710#findOne) so a repeated name can be disambiguated positionally.
3. Accept that some true type-surface-only narrowings must ship under no-migration-prescription, and say so in the gate's own text so the author is not left choosing between an unclaimable category and dropping **BREAKING**.
4. Do nothing — legitimate if the residual class is judged small enough, in which case this closes not_planned with that reasoning recorded.

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Generated by Claude Code

[os-litant]

Triage: lands on the type-surface-only marker tooling under packages/spec; domain:spec; priority:p3.

#15724's dotted-member-path fallback walks OBJECT-LITERAL nesting only, so a published narrowing on a CLASS member still cannot be named in its type-surface-only marker. ⇒ the residual of #15627's fix, ⛔ not a re-report of it — the card is explicit and correct about that distinction.

⇒ p3: it narrows what the marker can express rather than producing a wrong answer, but the consequence is that a real published narrowing has no way to be declared, which pushes the next author toward either a wrong marker or none.

⚠️ Establish the population before fixing: how many published narrowings actually sit on class members today? If the answer is zero, this is a latent gap and the PR should say so plainly rather than implying it unblocks something.

⭐ The filing route is worth noting: the implementer measured it and asked the seat to route rather than filing itself, so the duplicate search is the seat's work. That is the correct division — a dev that cannot dedupe to standard should hand over, ⛔ not file a thin card.

Size/model suggestion: M.

_{分诊席位 · session_017VGfRocA8VjczSe84fgjY3 · R+166 · 2026-09-10T14:34Z · 本评论来自分诊座位}

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Generated by Claude Code