fix(node): Rework node:child_process IPC (#24763)

Fixes https://github.com/denoland/deno/issues/24756. Fixes
https://github.com/denoland/deno/issues/24796.

This also gets vitest working when using
[`--pool=forks`](https://vitest.dev/guide/improving-performance#pool)
(which is the default as of vitest 2.0). Ref
https://github.com/denoland/deno/issues/23882.

---

This PR resolves a handful of issues with child_process IPC. In
particular:

- We didn't support sending typed array views over IPC
- Opening an IPC channel resulted in the event loop never exiting
- Sending a `null` over IPC would terminate the channel
- There was some UB in the read implementation (transmuting an `&[u8]`
to `&mut [u8]`)
- The `send` method wasn't returning anything, so there was no way to
signal backpressure (this also resulted in the benchmark
`child_process_ipc.mjs` being misleading, as it tried to respect
backpressure. That gave node much worse results at larger message sizes,
and gave us much worse results at smaller message sizes).
- We weren't setting up the `channel` property on the `process` global
(or on the `ChildProcess` object), and also didn't have a way to
ref/unref the channel
- Calling `kill` multiple times (or disconnecting the channel, then
calling kill) would throw an error
- Node couldn't spawn a deno subprocess and communicate with it over IPC

1 files changed, 1 insertions, 2 deletions

diff --git a/ext/node/ops/vm.rs b/ext/node/ops/vm.rs
index df631a51f..a44d84975 100644
--- a/ext/node/ops/vm.rs
+++ b/ext/node/ops/vm.rs
@@ -140,8 +140,7 @@ mod tests {
   #[test]
   fn test_run_in_this_context() {
     let platform = v8::new_default_platform(0, false).make_shared();
-    v8::V8::initialize_platform(platform);
-    v8::V8::initialize();
+    deno_core::JsRuntime::init_platform(Some(platform));
 
     let isolate = &mut v8::Isolate::new(Default::default());