[CI/UT][Graph] Add ut for torchair graph mode (#1103)

### What this PR does / why we need it?
Add ut for torchair graph mode on DeepSeekV3

### How was this patch tested?
CI passed with new added test.

---------

Signed-off-by: MengqingCao <cmq0113@163.com>
Signed-off-by: Mengqing Cao <cmq0113@163.com>

tests/conftest.py

@@ -17,6 +17,7 @@
 # Adapted from vllm-project/vllm/blob/main/tests/conftest.py
 #
 
+import contextlib
 import gc
 from typing import List, Optional, Tuple, TypeVar, Union
 
@@ -53,11 +54,17 @@ PromptAudioInput = _PromptMultiModalInput[Tuple[np.ndarray, int]]
 PromptVideoInput = _PromptMultiModalInput[np.ndarray]
 
 
-def cleanup_dist_env_and_memory():
+def cleanup_dist_env_and_memory(shutdown_ray: bool = False):
     destroy_model_parallel()
     destroy_distributed_environment()
+    with contextlib.suppress(AssertionError):
+        torch.distributed.destroy_process_group()
+    if shutdown_ray:
+        import ray  # Lazy import Ray
+        ray.shutdown()
     gc.collect()
     torch.npu.empty_cache()
+    torch.npu.reset_peak_memory_stats()
 
 
 class VllmRunner:

tests/multicard/test_torchair_graph_mode.py

@@ -0,0 +1,80 @@
+#
+# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
+# Copyright 2023 The vLLM team.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# This file is a part of the vllm-ascend project.
+#
+"""Compare the short outputs of HF and vLLM when using greedy sampling.
+
+Run `pytest tests/multicard/test_torchair_graph_mode.py`.
+"""
+import os
+
+import pytest
+
+from tests.conftest import VllmRunner
+
+os.environ["PYTORCH_NPU_ALLOC_CONF"] = "max_split_size_mb:256"
+
+
+@pytest.mark.skipif(os.getenv("VLLM_USE_V1") == "0",
+                    reason="torchair graph is not supported on v0")
+def test_e2e_deepseekv3_with_torchair(monkeypatch: pytest.MonkeyPatch):
+    with monkeypatch.context() as m:
+        m.setenv("VLLM_USE_MODELSCOPE", "True")
+        m.setenv("VLLM_WORKER_MULTIPROC_METHOD", "spawn")
+
+        example_prompts = [
+            "Hello, my name is",
+            "The president of the United States is",
+            "The capital of France is",
+            "The future of AI is",
+        ]
+        dtype = "half"
+        max_tokens = 5
+        # torchair is only work without chunked-prefill now
+        with VllmRunner(
+                "vllm-ascend/DeepSeek-V3-Pruning",
+                dtype=dtype,
+                tensor_parallel_size=4,
+                distributed_executor_backend="mp",
+                additional_config={
+                    "torchair_graph_config": {
+                        "enabled": True,
+                    },
+                    "ascend_scheduler_config": {
+                        "enabled": True,
+                    },
+                    "refresh": True,
+                },
+                enforce_eager=False,
+        ) as vllm_model:
+            # use greedy sampler to make sure the generated results are fix
+            vllm_output = vllm_model.generate_greedy(example_prompts,
+                                                     max_tokens)
+        # NOTE: vllm-ascend/DeepSeek-V3-Pruning is a random weight of
+        # DeepSeek-V3 with 2 hidden layers, thus the golden results seems
+        # inaccurate. This will only change if accuracy improves with the
+        # official weights of DeepSeek-V3.
+        golden_results = [
+            'Hello, my name is feasibility伸 spazio debtor添',
+            'The president of the United States is begg"""\n杭州风和 bestimm',
+            'The capital of France is frequentlyশามalinkAllowed',
+            'The future of AI is deleting俯احت怎么样了حراف',
+        ]
+
+        assert len(golden_results) == len(vllm_output)
+        for i in range(len(vllm_output)):
+            assert golden_results[i] == vllm_output[i][1]
+            print(f"Generated text: {vllm_output[i][1]!r}")