fix(provider-utils): make ReadableStream.cancel() properly finalize async iterators #9834
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lgrammel
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…sync iterators (#9834) ## Background `convertAsyncIteratorToReadableStream` didn't notify its source when a consumer called `cancel()`. This left async generators running even after the stream was cancelled. This affects any code that adapts `convertAsyncIteratorToReadableStream`, e.g. LlamaIndex adapter ## Manual Verification Checked a real streaming flow (OpenAI via LlamaIndex): read a few chunks, then cancel. Next read returns done=true and no further chunks are produced. ## Summary - Fixed `convertAsyncIteratorToReadableStream` to properly call `iterator.return()` when the stream is cancelled - Added unit tests
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✅ Backport PR created: #9881 |
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Background
convertAsyncIteratorToReadableStreamdidn't notify its source when a consumer calledcancel(). This left async generators running even after the stream was cancelled.This affects any code that adapts
convertAsyncIteratorToReadableStream, e.g. LlamaIndex adapterManual Verification
Checked a real streaming flow (OpenAI via LlamaIndex): read a few chunks, then cancel. Next read returns done=true and no further chunks are produced.
Summary
convertAsyncIteratorToReadableStreamto properly calliterator.return()when the stream is cancelledChecklist