dillon1000/react

[Flight] Ignore bound-anonymous-fn resources as they're not considered I/O (#34911)

When you create a snapshot from an AsyncLocalStorage in Node.js, that
creates a new bound AsyncResource which everything runs inside of.


https://github.com/nodejs/node/blob/3437e1c4bd529e51d96ea581b6435bbeb77ef524/lib/internal/async_local_storage/async_hooks.js#L61-L67

This resource is itself tracked by our async debug tracking as I/O. We
can't really distinguish these in general from other AsyncResources
which are I/O.

However, by default they're given the name `"bound-anonymous-fn"` if you
pass it an anonymous function or in the case of a snapshot, that's
built-in:


https://github.com/nodejs/node/blob/3437e1c4bd529e51d96ea581b6435bbeb77ef524/lib/async_hooks.js#L262-L263

We can at least assume that these are non-I/O. If you want to ensure
that a bound resource is not considered I/O, you can ensure your
function isn't assigned a name or give it this explicit name.

The other issue here is that, the sequencing here is that we track the
callsite of the `.snapshot()` or `.bind()` call as the trigger. So if
that was outside of render for example, then it would be considered
non-I/O. However, this might miss stuff if you resolve promises inside
the `.run()` of the snapshot if the `.run()` call itself was spawned by
I/O which should be tracked. Time will tell if those patterns appear.
However, in cases like nested renders (e.g. Next.js's "use cache") then
restoring it as if it was outside the parent render is what you do want.