Replace libuv usage with napi_async_work?

[littledivy]

Hi! I'm working on a N-API implementation on top of deno_core and Tokio (https://github.com/littledivy/napi-rusty-v8/) and we're trying to get all of parcel's native modules to work. The implementation is eventually going to be merged in Deno.

Since this is built on top of Tokio, we're avoiding to expose libuv polyfills. This makes @parcel/watcher incompatible. Would it be possible to use napi_async_work instead of libuv for the Watcher?

[devongovett]

Last I checked (which was a few years ago, so may have changed), there was no equivalent of uv_async_send as used here:

watcher/src/Watcher.cc

Line 92 in caf372c

uv_async_send(mAsync);

This is different from napi_async_work, because we execute a JS callback multiple times. We use uv_async_send to call into the JS thread from a background thread where watching is occurring.

Are you aware of a way to do this with napi?

[littledivy]

Oh yeah, for uv_async_t there is Napi::ThreadSafeFunction