Avoid creating a Napi handle scope within a finalizer

[Jarred-Sumner]

What does this PR do?

This makes napi handle scopes optional, and we ignore them when they're not set.

Fixes https://discord.com/channels/876711213126520882/1282959007589601280/1282959007589601280

This mitigates a crash where a napi package creates a handle scope within a finalizer. Any object allocation within that finalizer would still fail, but the act of creating a handle scope at all inside a finalizer fails since it is an allocation.

How did you verify your code works?

I verified the crash is fixed manually.

This needs a test. The test would do something like:

• Create a napi ref wrapping an object
• The napi ref's finalizer function should open a handle scope
• Allocate repeatedly until the napi ref's finalizer is called

[robobun]

❌ @190n, your commit 91310bf has 10 failures in #3329:

test/js/bun/spawn/spawn.test.ts - timeout on 🪟 x64-baseline

test/js/node/fs/fs.test.ts - 1 failing on 🪟 x64

test/js/bun/spawn/spawn-streaming-stdin.test.ts - 1 failing on 🪟 x64-baseline

test/js/bun/spawn/spawn-streaming-stdin.test.ts - 1 failing on 🪟 x64

test/cli/hot/watch.test.ts - 1 failing on 🪟 x64-baseline

test/cli/hot/watch.test.ts - 1 failing on 🪟 x64

test/js/web/streams/streams.test.js - 1 failing on 🍎 13 aarch64

test/cli/run/require-cache.test.ts - 1 failing on 🍎 13 x64

test/cli/watch/watch.test.ts - 2 failing on 🪟 x64-baseline

test/cli/watch/watch.test.ts - 2 failing on 🪟 x64

test/bundler/bun-build-api.test.ts - 1 failing on 🪟 x64-baseline

test/bundler/bun-build-api.test.ts - 1 failing on 🪟 x64

test/js/bun/http/bun-serve-static.test.ts - 10 failing on 🍎 13 aarch64

test/cli/install/registry/bun-install-registry.test.ts - 2 failing on 🍎 13 aarch64

test/cli/install/registry/bun-install-registry.test.ts - 1 failing on 🪟 x64-baseline

test/cli/install/registry/bun-install-registry.test.ts - 1 failing on 🪟 x64

[190n]

It looks like nodejs/node-addon-api#1409 will (once it lands in a release) also fix this, as they now intentionally defer the execution of finalizers instead of relying on Node.js to do it:

#if (defined(NAPI_EXPERIMENTAL) &&                                             \
     defined(NODE_API_EXPERIMENTAL_HAS_POST_FINALIZER))
template <napi_finalize finalizer>
inline void PostFinalizerWrapper(node_api_nogc_env nogc_env,
                                 void* data,
                                 void* hint) {
  napi_status status = node_api_post_finalizer(nogc_env, finalizer, data, hint);
  NAPI_FATAL_IF_FAILED(
      status, "PostFinalizerWrapper", "node_api_post_finalizer failed");
}
#else
template <napi_finalize finalizer>
inline void PostFinalizerWrapper(napi_env env, void* data, void* hint) {
  finalizer(env, data, hint);
}
#endif

But this solution will do for now. I'll write a test -- I might see if we can pass a JS callback into the NAPI functions that calls Bun.gc instead of trying to trigger it via a bunch of allocations, as that will make the other GC tests faster too. But I'll have to make sure that that does actually reproduce GC bugs.

[190n]

needs a test

[190n]

the tests crash node