fix: prevent stack overflow in toBase64 for large inputs#961
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Scottcjn wants to merge 1 commit intoanthropics:mainfrom
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fix: prevent stack overflow in toBase64 for large inputs#961Scottcjn wants to merge 1 commit intoanthropics:mainfrom
Scottcjn wants to merge 1 commit intoanthropics:mainfrom
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String.fromCharCode.apply() has a maximum argument count limit (~65536) which causes "Maximum call stack size exceeded" when encoding Uint8Arrays larger than ~100KB. Process bytes in 8192-byte chunks instead. Fixes anthropics#932 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
toBase64usesString.fromCharCode.apply(null, data)in thebtoapath, which passes the entireUint8Arrayas individual arguments. JavaScript engines have a maximum argument count (~65,536), so inputs larger than ~100KB causeRangeError: Maximum call stack size exceeded.String.fromCharCode(...data.subarray(i, i + chunkSize)), keeping each call well under the limit.Uint8ArraythroughtoBase64/fromBase64in bothBufferandbtoamodes.Fixes #932
Test plan
toBase64andfromBase64tests pass (both Buffer and atob modes)🤖 Generated with Claude Code