zeekay 9d9e477978 v1/codegen: emit REPEATED nested objects (repeated message, zero-copy) ...

The repeated-message wire shape: a list whose elements carry their own
variable-length tails (string/bytes/nested), which the fixed-stride inline
List cannot hold. Completes proto field-shape coverage in the runtime —
map<k,v> reduces to a repeated {key,value} entry, so this is its keystone too.

Composition, not a new wire concept: ListNested = List ∘ NestedAt. The list
slots are a contiguous stride-4 object-pointer array; each pointer is
followed exactly as a singular nested pointer to an out-of-line tailed View.

Runtime:
- builder.go: ListBuilder.AddObjectPtr(targetPos) — appends a signed 4-byte
  relative object pointer (the repeated-message element kind).
- v1/list_nested.go: ListNested[N] (Len/At/All/IsZero), ListNestedAt[S,N]
  (read), WriteListNested[S,N] + NestedElemSetter[N] (write). Same audited
  bounds discipline as Object.Object / ListStride (RED-HIGH-1/2 inherited).

Codegen:
- elemIsTailed: a list element with a string/bytes/nested/list sub-field
  auto-routes to ListNested/WriteListNested/ListNestedAt; scalar-only
  elements stay in the tighter inline List/WriteList/ListAt. One Elem
  declaration, the generator picks the correct encoding.

Proven end-to-end: runtime roundtrip (3 elements each with its OWN string
tail, via At and All, + empty), emit routing test (tailed->ListNested,
scalar-only->List), and a generated-code wire roundtrip (testpkg/repeatwire).
Root zap + full v1+codegen suite green; scalar listwire unchanged (no regression).

2026-06-23 16:38:05 -07:00

..

main.go

v1/codegen: emit REPEATED nested objects (repeated message, zero-copy)

2026-06-23 16:38:05 -07:00