Localize cur_batch field in Scheduler to avoid field-based state access (#29407)

test/registered/chunked_prefill/test_scripted_core_4gpu.py

@@ -77,7 +77,10 @@ class TestScriptedPpChunkSweep(ScriptedTestCase):
                 scheduler.chunked_req is None
                 and len(scheduler.waiting_queue) == 0
                 and all(x.is_empty() for x in scheduler.running_mbs)
-                and (scheduler.cur_batch is None or scheduler.cur_batch.is_empty())
+                and (
+                    scheduler.cur_batch_for_debug is None
+                    or scheduler.cur_batch_for_debug.is_empty()
+                )
                 and (scheduler.last_batch is None or scheduler.last_batch.is_empty())
             )
             if in_flight and queues_clear:

test/registered/unit/disaggregation/test_decode_queue_cleanup.py

@@ -193,7 +193,7 @@ class TestDecodeQueueCleanup(CustomTestCase):
         scheduler.dllm_manager = MagicMock()
         scheduler.dllm_manager.any_staging_reqs.return_value = False
         scheduler.last_batch = None
-        scheduler.cur_batch = None
+        scheduler.cur_batch_for_debug = None
         scheduler.enable_overlap = False
         scheduler.ps = SimpleNamespace(pp_size=1)
         scheduler.running_mbs = []

test/registered/unit/hardware_backend/mlx/test_attention_patching.py

@@ -1135,7 +1135,7 @@ class TestMlxOverlapScheduler(unittest.TestCase):
         scheduler.waiting_queue = []
         scheduler.result_queue = deque()
         scheduler.future_map = SimpleNamespace()
-        scheduler.cur_batch = None
+        scheduler.cur_batch_for_debug = None
         scheduler.last_batch = None
         scheduler.tp_worker = SimpleNamespace(
             async_forward_batch_generation_mlx=fake_forward

test/registered/unit/managers/test_scheduler_pause_generation.py

@@ -26,7 +26,7 @@ class TestSchedulerPauseGeneration(unittest.TestCase):
         scheduler._engine_paused = False
         scheduler.enable_overlap = False
         scheduler.last_batch = None
-        scheduler.cur_batch = None
+        scheduler.cur_batch_for_debug = None
         scheduler.chunked_req = None
         scheduler.running_batch = MagicMock()
         scheduler.running_batch.reqs = []
@@ -59,11 +59,11 @@ class TestSchedulerPauseGeneration(unittest.TestCase):
         """in_place pause should only set _engine_paused and return."""
         scheduler = self._new_scheduler()
         scheduler.last_batch = MagicMock()
-        scheduler.cur_batch = MagicMock()
+        scheduler.cur_batch_for_debug = MagicMock()
         scheduler.chunked_req = MagicMock()
 
         original_last_batch = scheduler.last_batch
-        original_cur_batch = scheduler.cur_batch
+        original_cur_batch = scheduler.cur_batch_for_debug
         original_chunked_req = scheduler.chunked_req
 
         scheduler.pause_generation(PauseGenerationReqInput(mode="in_place"))
@@ -71,7 +71,7 @@ class TestSchedulerPauseGeneration(unittest.TestCase):
         self.assertTrue(scheduler._engine_paused)
         # All state must be preserved — no mutation
         self.assertIs(scheduler.last_batch, original_last_batch)
-        self.assertIs(scheduler.cur_batch, original_cur_batch)
+        self.assertIs(scheduler.cur_batch_for_debug, original_cur_batch)
         self.assertIs(scheduler.chunked_req, original_chunked_req)
 
     def test_inplace_does_not_drain_overlap_queue(self):
@@ -99,17 +99,17 @@ class TestSchedulerPauseGeneration(unittest.TestCase):
         scheduler.running_batch.merge_batch.assert_not_called()
 
     def test_abort_clears_state(self):
-        """abort mode should clear last_batch and cur_batch."""
+        """abort mode should clear last_batch and cur_batch_for_debug."""
         scheduler = self._new_scheduler()
         scheduler.last_batch = MagicMock()
         scheduler.last_batch.forward_mode.is_extend.return_value = False
-        scheduler.cur_batch = MagicMock()
+        scheduler.cur_batch_for_debug = MagicMock()
 
         scheduler.pause_generation(PauseGenerationReqInput(mode="abort"))
 
         self.assertTrue(scheduler._engine_paused)
         self.assertIsNone(scheduler.last_batch)
-        self.assertIsNone(scheduler.cur_batch)
+        self.assertIsNone(scheduler.cur_batch_for_debug)
 
     def test_retract_clears_running_batch(self):
         """retract mode should retract all requests from running_batch."""