perf(wasm): cache container kind() on JS wrappers - #1085
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kind() returns a constant string per container class but the wasm-bindgen glue crossed into WASM and allocated a fresh JS string on every call. Memoize it once per class next to the existing per-wrapper id cache. Measured with scripts/measure-container-id.cjs (1M repeated reads): 164.5 ms -> 1.0 ms, wasm string decodes 1,000,000 -> 0.
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Stack: 2/6 — merge order: #1093 → #1085 → #1086 → #1087 → #1090 → #1091
Summary
kind()on container wrappers (LoroMap/LoroList/LoroText/LoroTree/LoroMovableList/LoroCounter) returns a constant string per class, but every call crossed into WASM and allocated a fresh JS string viagetStringFromWasm0. On a real document with ~70k containers, loro-mirror-style traversal calledkind()230k times per full read (andid333k times; theidcache already landed in #1073).This extends the existing
container_id_cache_patch.jsmechanism with a class-level memo forkind(). Reads afterfree()still raise wasm-bindgen's null-pointer error (the memo is bypassed for a zero__wbg_ptr), and Rust-sidekind()reads injs_to_containershare the same memo.Measured (scripts/measure-container-id.cjs, 1M repeated reads of one wrapper)
Tests
tests/container_id_cache.test.ts: repeatedkind()calls return the same string with zero additional wasm string decodes; at most one decode per container class; post-free()reads still throw.tsc --noEmitclean.Wasm binary size
No change — this is a pure JS-glue patch.
Part 1 of the bulk-read series; the follow-up (per-container/range deep reads) stacks on this branch.