Form C (`insert into T (vals)`) shared the `(` opener with Form A,
so its paren was an untyped Repeated(Choice(literal, ident)) — values
weren't type- or count-checked at parse time (handoff-12 §2.2).
New Node::Lookahead variant: a factory that peeks the source. The
insert first-paren factory inspects the first token — a value literal
routes the contents through the typed column_value_list (Form B
dispatch contract: per-non-auto-column typed slots); an identifier or
empty paren routes to a Form A column-name list. So Form C now gets
the same per-column typed slots, hints, and parse-time type/count
checking Form B has.
The explicit-Choice-branch split is impossible here (committed-choice
semantics commit after `(` matches); lookahead is the only route, and
DynamicSubgrammar factories couldn't see the source. Node::Lookahead
is not memoized — its output depends on source — but it returns only
a small node (a Repeated, or a thin DynamicSubgrammar wrapper that
delegates to the memoized column_value_list).
`insert into T (` now cleanly shows Form A column candidates instead
of mixed Form-A/C suggestions. Form C matrix tests updated for the
type-aware behaviour.
34 new tests covering:
- Form C bare-value-list (happy path + Form-A-recovery + type-unaware grammar limitation per handoff §2.2)
- update with WHERE (column-narrowing invariant per handoff §1 bug E1; typed-slot prose for assignments and where filters)
- update --all-rows (filter-clause requirement per ADR-0014)
- delete with WHERE (column-narrowing; typed-slot prose for where filters)
- delete --all-rows
859 baseline -> 931 passing. No bugs surfaced — the data-mutation
command family was already well-shaped post-Phase-D.
Per docs/handoff/20260515-handoff-12.md §1. Systematic per-position
coverage of (state, hint, completion, parse_result) across canonical
schema shapes; submodule per command family. Insert Form A covers 23
cursor positions across serial-PK, text-PK, multi-table, and
every-Type schemas. Both bugs fixed in the previous commit were
surfaced by these tests.
Shared helpers under tests/typing_surface/mod.rs: 5 canonical schema
shapes, assess() helper, property-assertion shortcuts, and a snap!
macro that wraps insta with a stable per-cell suffix.
859 -> 885 tests passing; 1 ignored (pre-existing doc-test).
claude@clouddev1