[backport] Turbopack: flush Node.js worker IPC on error (#84079)

Author: mischnic

turbopack/crates/turbopack-node/js/src/ipc/index.ts

@@ -168,18 +168,20 @@ function createIpc<TIncoming, TOutgoing>(
     sendReady,
 
     async sendError(error: Error): Promise<never> {
+      let failed = false
       try {
         await send({
           type: 'error',
           ...structuredError(error),
         })
       } catch (err) {
+        // There's nothing we can do about errors that happen after this point, we can't tell anyone
+        // about them.
         console.error('failed to send error back to rust:', err)
-        // ignore and exit anyway
-        process.exit(1)
+        failed = true
       }
-
-      process.exit(0)
+      await new Promise<void>((res) => socket.end(() => res()))
+      process.exit(failed ? 1 : 0)
     },
   }
 }