test(desktop): release the held Stop only once the result waits on its lock

Author: waleedlatif1

apps/sim/lib/desktop/application/executor.integration.ts

@@ -553,22 +553,31 @@ describe.runIf(Boolean(redisUrl))('desktop background executor protocol', () =>
       const { executionToken } = await claim(desktop.principal, desktop.deviceId, toolCallId)
 
       /** Stop closes admission on the run row; hold its transaction open while the result arrives. */
-      const stopHeld = createDeferred<void>()
+      const stopHeld = createDeferred<number>()
       const releaseStop = createDeferred<void>()
       const stopping = db.transaction(async (tx) => {
         await tx
           .update(copilotRuns)
           .set({ toolAdmissionClosedAt: sql`now()` })
           .where(eq(copilotRuns.id, run.runId))
-        stopHeld.resolve()
+        const [backend] = await tx.execute<{ pid: number }>(sql`SELECT pg_backend_pid() AS pid`)
+        stopHeld.resolve(backend.pid)
         await releaseStop.promise
       })
-      await stopHeld.promise
+      const stopPid = await stopHeld.promise
       const completing = completeDesktopTool.execute({
         principal: desktop.principal,
         input: { deviceId: desktop.deviceId, toolCallId, executionToken, status: 'success' },
       })
-      await sleep(300)
+      /** Release Stop only once the result is queued behind its lock on the run row. */
+      await expect
+        .poll(async () => {
+          const [waiter] = await db.execute<{ pid: number }>(sql`
+            SELECT pid FROM pg_stat_activity WHERE wait_event_type = 'Lock'
+              AND ${stopPid}::int = ANY(pg_blocking_pids(pid)) LIMIT 1`)
+          return Boolean(waiter)
+        })
+        .toBe(true)
       releaseStop.resolve()
       await stopping