Fix wasteful allocations and minor perf improvements#2369
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lahma merged 3 commits intoMar 26, 2026
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- SetPrototype: Remove unnecessary JsSet/HashSet copies in IsDisjointFrom, IsSubsetOf, and IsSupersetOf that were allocating full set copies for read-only or boolean-returning operations - SetPrototype.IsSubsetOf: Remove redundant always-true condition guard - TypeConverter: Cache BigInteger.Pow(2, 64) and BigInteger.Pow(2, 63) as static readonly fields instead of recomputing on every call - JintBinaryExpression: Cache Math.Abs(baseValue) in exponentiation instead of calling it 4 times - HybridDictionary: Replace Enumerable.Empty<T>().GetEnumerator() with Array.Empty<T>() cast to avoid LINQ enumerator allocation Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Both Enumerable.Empty<T>().GetEnumerator() and Array.Empty<T>() cast produce the same SZGenericArrayEnumerator allocation. The original code is cleaner and callers already null-check before iterating, so this path is rarely hit. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
…rted features - Add TaskInterop section under Asynchronous Execution explaining automatic .NET Task/ValueTask to JavaScript Promise conversion with usage examples - Add Decorators to ECMAScript proposals (no version yet) feature list Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
lahma
enabled auto-merge (squash)
March 26, 2026 16:30
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Summary
JsSet/HashSetcopies inIsDisjointFrom,IsSubsetOf, andIsSupersetOfthat were allocating full set copies for read-only or boolean-returning operationsBigInteger.Pow(2, 64)andBigInteger.Pow(2, 63)asstatic readonlyfields instead of recomputing on everyToBigInt64/ToBigUint64callMath.Abs(baseValue)in exponentiation instead of calling it 4 timesTest plan
Jint.Tests— 2,807 passed, 0 failedJint.Tests.Test262— 95,985 passed, 0 failed🤖 Generated with Claude Code