worker: wake the loop when a worker stops itself from an immediate (process.exit() / uncaught error)

src/jsc/web_worker.rs

@@ -1093,13 +1093,9 @@ impl WebWorker {
         // process.exit() from an exit handler does not re-arm the trap.
         let vm_ptr = self.vm_ptr();
         if !vm_ptr.is_null() {
+            // From an immediate this runs before the turn's poll; the wake is what ends it.
             // SAFETY: this thread's live VM.
-            unsafe {
-                // As for a parent's terminate(): nothing more may enter script
-                // (Node's `Stop(env)` on the worker's own exit).
-                (*vm_ptr).handle_ref().stop();
-                (*vm_ptr).jsc_vm().notify_need_termination();
-            }
+            unsafe { (*vm_ptr).handle_ref().request_termination() };
         }
     }
 
@@ -1251,20 +1247,8 @@ fn on_unhandled_rejection(
     // second time (a second `workerGlobalScopeDestroyed` → double deref of
     // the proxy's thread-held reference).
     //
-    // Instead, arm the JSC termination trap so any further JS halts at the
-    // next safepoint, and let the stack unwind normally back to `spin()`,
-    // whose loop observes `requested_terminate` and reaches the single
-    // `shutdown()` call at its bottom with no live JSC frames above it. The
-    // promise-rejection path in `spin()` (line ~1044) gets there even sooner:
-    // `uncaught_exception` returns `handled == false`, so `spin()` calls
-    // `return self.shutdown()` directly — same observable ordering.
-    // `vm.jsc_vm` is the worker's live `JSC::VM*` (we just used it via
-    // `global_object`); `notify_need_termination` is documented thread-safe
-    // (VMTraps). The gate closes with it, as for exit()/terminate(): the
-    // native→JS entries still reached this tick refuse rather than run into
-    // the pending termination.
-    vm.handle_ref().stop();
-    vm.jsc_vm().notify_need_termination();
+    // Instead, request the stop as `exit()` does and unwind to `spin()`'s `shutdown()`.
+    vm.handle_ref().request_termination();
 }
 
 /// Resolve a worker entry-point specifier to a path the module loader can

test/js/node/worker_threads/worker_threads.test.ts

@@ -2307,6 +2307,51 @@ test("closing the only ref'd port from setImmediate lets the process exit", asyn
   expect(exitCode).toBe(0);
 });
 
+// A worker's own stop requests (process.exit(), an uncaught error) have to wake
+// its loop the way the parent's terminate() does: made from an immediate they
+// land after the turn's tick and before its poll, and the run loop only looks
+// for them again once the poll returns. With a parentPort listener keeping the
+// loop alive, nothing else ends that poll: the exit used to wait for the idle GC
+// timer (about a second), and without it (disabled here) never happened.
+describe("a worker that stops itself from an immediate exits right away", () => {
+  test.concurrent.each([
+    ["process.exit()", "process.exit(7);", { errors: [], code: 7 }],
+    [
+      "process.exit() from a nextTick the immediate queued",
+      "process.nextTick(() => process.exit(7));",
+      { errors: [], code: 7 },
+    ],
+    ["an uncaught exception", 'throw new Error("boom");', { errors: ["boom"], code: 1 }],
+  ])("%s", async (_label, stop, expected) => {
+    const workerSrc = `const { parentPort } = require("node:worker_threads");
+      parentPort.on("message", () => {});
+      // Scheduled a little after startup so the worker's startup GC timers have
+      // fired by then and nothing is left that would end the poll on its own.
+      setTimeout(() => setImmediate(() => { parentPort.postMessage("stopping"); ${stop} }), 300);`;
+    await using proc = Bun.spawn({
+      cmd: [
+        bunExe(),
+        "-e",
+        `const { Worker } = require("node:worker_threads");
+         const w = new Worker(${JSON.stringify(workerSrc)}, { eval: true });
+         const seen = { messages: [], errors: [] };
+         w.on("message", m => seen.messages.push(m));
+         w.on("error", e => seen.errors.push(e.message));
+         w.on("exit", code => console.log(JSON.stringify({ ...seen, code })));`,
+      ],
+      env: { ...bunEnv, BUN_GC_TIMER_DISABLE: "1" },
+      stdout: "pipe",
+      stderr: "pipe",
+    });
+    const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+    expect({ stdout, stderr, exitCode }).toEqual({
+      stdout: JSON.stringify({ messages: ["stopping"], ...expected }) + "\n",
+      stderr: "",
+      exitCode: 0,
+    });
+  });
+});
+
 // Node's setupPortReferencing: the parent side of parentPort keeps the parent
 // alive while the Worker has 'message' listeners, independently of unref().
 test("an unref'ed worker with a 'message' listener still delivers to the parent", async () => {