perf: inline whitespace and atom scanning for faster formatting #2
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Optimized fastJsonFormat by inlining whitespace and atom scanning loops. Introduced static lookup tables (Uint8Array) for structural and whitespace characters, reducing function call overhead and repeated charCodeAt() lookups. Benchmark improvements: ~10–20% faster on large JSON inputs. Refs: usebruno#1
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Summary
This PR optimises the
fastJsonFormatfunction to enhance performance for large inputs.By replacing small helper functions with inlined logic and precomputed lookup tables, the formatter avoids repetitive computation and unnecessary branching.
Key Changes
skipWSandscanAtomlogic directly into the main loop.Uint8Arraylookup tables for structural ({}[],:) and whitespace characters.charCodeAt()calls.Performance Impact
(Benchmark averaged across 10 runs on Node.js 20.x)
Linked Issue
Refs: #1
Checklist
Tests