- Merge: defensive copy `new List<ElementInfo>(derived.Children)` so a
later mutation of the merged result or the input can't corrupt the other
- Merge: add comment on Width/Height 0-sentinel (Plan-1 safe; Plan-2
limitation and float?-upgrade path documented inline)
- Test: replace mid-sentence "Wait —" authoring trace in
EdgeFlagsToAnchors_ValueThree_FallsBackToTopLeft with a clean
conclusion-first summary of the value-3 mapping rule
9/9 ElementReaderTests pass; 0 build errors.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Implements Task 2 of the LayoutDesc Importer (Plan 1 — vitals conformance).
- ElementInfo POCO: GL-free/dat-free snapshot of a resolved layout element.
Shape matches the plan spec exactly (Id, Type as uint, X/Y/Width/Height as
float, raw Left/Top/Right/Bottom uint edge flags, ReadOrder, FontDid, StateMedia
dict, Children list). Tasks 3–6 depend on this shape.
- ElementReader.ToAnchors(uint,uint,uint,uint): maps dat edge-flag values
(0=none, 1=near-pin, 2=far-pin, 3=floating-center, 4=stretch) to AnchorEdges
bit flags. Corrects the plan's stale assumption that value 4 was the only anchor
trigger; the verified format doc §4 shows 1→Left/Top, 2→Right/Bottom, 4→both.
All-zero falls back to Left|Top (default pin top-left).
- ElementReader.Merge(base_, derived): inheritance merge mirroring BaseElement/
BaseLayoutId. Derived scalars win when non-zero; position/edge-flags/ReadOrder
always from derived; StateMedia merged (base defaults, derived overrides);
Children from derived only.
TDD: tests written first (9 tests covering ToAnchors near-pin/far-pin/stretch/
zero/value-3, Merge scalar override/font inheritance/StateMedia merge/children).
All 9 pass; dotnet build 0 errors 0 warnings.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
