fix: prevent memory leak in Blob.prototype.stream() upon cancel#63772
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EduardF1 wants to merge 1 commit into
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fix: prevent memory leak in Blob.prototype.stream() upon cancel#63772EduardF1 wants to merge 1 commit into
EduardF1 wants to merge 1 commit into
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Description
Fixes #63574
Currently, calling
.cancel()on a Blob stream correctly rejects pending JS pulls but leaves the internal C++ reader wakeup callback pinned in memory. This creates a detached eternal handle spanning across the C++ and JS boundary, retaining the source ArrayBuffer perpetually.This patch surgicaly modifies the
cancellifecycle to explicitly invokereader.setWakeup(undefined). This severs the cyclic GC reference chain between the nativeNode / DataQueueand the JavaScript engine, allowing V8 to correctly garbage collect the 1MiB source buffers when the stream is aborted.Testing
Verified against the user's reproduction snippet running with
--expose-gc. After 200 stream cancellations, the RSS/arrayBuffer allocation correctly dropped from ~201.0 MiB back down to 1.0 MiB baseline.