perf(decode): parse struct destinations without the value tree

Assisted-by: GLM 5.3 Flash
2026-09-22 15:59:03 +02:00
parent ee32490452
commit a7d0041259
7 changed files with 1971 additions and 6 deletions
@@ -188,6 +188,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 **Performance**

+- Struct destinations decode directly: for a type the direct skeleton can
+  model, the parser resolves tables and keys against the struct schema while
+  the document scans and no intermediate value tree is kept. The strict
+  decode of the representative document drops from 168 to 160 allocations
+  per call against the tree path in the same process, and the 2000-element
+  document reaches allocation parity; every document the skeleton cannot
+  model falls back to the tree path and its exact error contracts. A
+  differential fuzz target decodes every generated document both ways.
 - Marshal writes plain scalars and typed scalar arrays straight from their
  reflect cells instead of boxing them into interface values first, and skips
  the per-element resolution for arrays that can never take the `[[header]]`