[Flight] Exclude RSC Stream if the stream resolves in a task #34838
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sebmarkbage
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Oct 14, 2025
| wakeChunk(resolveListeners, handler.value, initializedChunk); | ||
| } else { | ||
| if (__DEV__) { | ||
| moveDebugInfoFromChunkToInnerValue(initializedChunk, handler.value); |
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This PR surfaced another bug.
It turns out that resolveChunkDebugInfo adds a .then() listener which forces the wakeChunk pass to be taken. If that doesn't happen, then wakeChunk isn't called.
We forgot that we need to call moveDebugInfoFromChunkToInnerValue everywhere we initialize but don't call wakeChunk. We could potentially just move this out and all it next to all these instead of inside wakeChunk.
sebmarkbage
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Oct 14, 2025
| return null; | ||
| } | ||
| visited.add(node); | ||
| if (node.end >= 0 && node.end <= request.timeOrigin) { |
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Another drive-by fix somewhat related. Most of the time this is covered by the PROMISE_NODE path but it really applies to all of these so we can just apply it universally.
unstubbable
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Oct 14, 2025
Ignore any path that completed before the render started.
This is a bit more optimized because it doesn't create an intermediate unnecessary array.
…eners wakeChunk doesn't get called if we initialize a value without any listeners.
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This was referenced Oct 14, 2025
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Stacked on #34836.
Normally we consider microtasks, next ticks and setImmediates not as I/O to be tracked by debug info. We also exclude things that finished loading before we started rendering. That's consider cached.
This avoids emitting the "RSC stream" debug info if the stream finished within a
setTimeout. I.e. it was likely cached and so it wouldn't add any additional suspending.Unfortunately, this will often happen if you use the
createFromReadableStreamAPI to consumeresponse.bodybecause by the time you get there you'll likely have at least received part of the body already.