[Bugfix][Engine] Make abort idempotent during shutdown (#6327)

Signed-off-by: Allen Wu <allenwu2795@gmail.com>
Co-authored-by: TRAE CLI <noreply@bytedance.com>
Co-authored-by: TRAE CLI <traecli@bytedance.com>

tests/engine/test_async_omni_engine_input.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
 import pytest
 import torch
 from pytest_mock import MockerFixture
@@ -14,6 +17,104 @@ from vllm_omni.model_executor.stage_input_processors.bagel import ExpandedPrompt
 pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
 
 
+class _SyntheticSyncQueueShutDownError(Exception):
+    pass
+
+
+def test_abort_is_noop_for_empty_request_ids(mocker: MockerFixture):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = False
+    engine.request_queue = mocker.Mock()
+
+    engine.abort([])
+
+    engine.request_queue.sync_q.put.assert_not_called()
+
+
+def test_abort_is_noop_after_shutdown_starts(mocker: MockerFixture):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = True
+    engine.request_queue = mocker.Mock()
+
+    engine.abort(["req-1"])
+
+    engine.request_queue.sync_q.put.assert_not_called()
+
+
+def test_abort_tolerates_queue_close_race_during_shutdown(mocker: MockerFixture):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = False
+    engine.request_queue = mocker.Mock()
+    mocker.patch(
+        "vllm_omni.engine.async_engine_utils._JANUS_SYNC_QUEUE_SHUTDOWN",
+        _SyntheticSyncQueueShutDownError,
+    )
+
+    def close_queue_during_abort(*args, **kwargs):
+        del args, kwargs
+        engine._shutdown_called = True
+        raise _SyntheticSyncQueueShutDownError
+
+    engine.request_queue.sync_q.put.side_effect = close_queue_during_abort
+
+    engine.abort(["req-1"])
+
+
+def test_abort_tolerates_legacy_janus_close_error_during_shutdown(mocker: MockerFixture):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = False
+    engine.request_queue = mocker.Mock()
+    mocker.patch(
+        "vllm_omni.engine.async_engine_utils._JANUS_SYNC_QUEUE_SHUTDOWN",
+        None,
+    )
+
+    def close_queue_during_abort(*args, **kwargs):
+        del args, kwargs
+        engine._shutdown_called = True
+        raise RuntimeError("Operation on the closed queue is forbidden")
+
+    engine.request_queue.sync_q.put.side_effect = close_queue_during_abort
+
+    engine.abort(["req-1"])
+
+
+def test_abort_surfaces_unrelated_legacy_runtime_error_during_shutdown(
+    mocker: MockerFixture,
+):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = False
+    engine.request_queue = mocker.Mock()
+    mocker.patch(
+        "vllm_omni.engine.async_engine_utils._JANUS_SYNC_QUEUE_SHUTDOWN",
+        None,
+    )
+
+    def fail_during_abort(*args, **kwargs):
+        del args, kwargs
+        engine._shutdown_called = True
+        raise RuntimeError("unrelated queue failure")
+
+    engine.request_queue.sync_q.put.side_effect = fail_during_abort
+
+    with pytest.raises(RuntimeError, match="unrelated queue failure"):
+        engine.abort(["req-1"])
+
+
+def test_abort_surfaces_unexpected_closed_queue(mocker: MockerFixture):
+    engine = object.__new__(AsyncOmniEngine)
+    engine._shutdown_called = False
+    engine.request_queue = mocker.Mock()
+    mocker.patch(
+        "vllm_omni.engine.async_engine_utils._JANUS_SYNC_QUEUE_SHUTDOWN",
+        _SyntheticSyncQueueShutDownError,
+    )
+    engine.request_queue.sync_q.put.side_effect = _SyntheticSyncQueueShutDownError
+
+    with pytest.raises(_SyntheticSyncQueueShutDownError):
+        engine.abort(["req-1"])
+
+
 def _make_engine_core_request(request_id: str = "req-1") -> EngineCoreRequest:
     return EngineCoreRequest(
         request_id=request_id,