fix(tests): clear envs cache in VLLM_MAX_N_SEQUENCES tests

Signed-off-by: jperezde <jperezde@redhat.com>

Author: jperezdealgaba

tests/entrypoints/openai/chat_completion/test_chat.py

@@ -1022,10 +1022,16 @@ def test_chat_completion_request_n_parameter_various_values():
         )
 
 
-def test_chat_completion_request_n_parameter_exceeds_default_limit():
+def test_chat_completion_request_n_parameter_exceeds_default_limit(
+    monkeypatch: pytest.MonkeyPatch,
+):
     """Test that n values exceeding the default limit are rejected."""
     import vllm.envs as envs
 
+    monkeypatch.delenv("VLLM_MAX_N_SEQUENCES", raising=False)
+    if hasattr(envs.__getattr__, "cache_clear"):
+        envs.__getattr__.cache_clear()
+
     max_n = envs.VLLM_MAX_N_SEQUENCES
     request = ChatCompletionRequest(
         model="test-model",
@@ -1041,10 +1047,16 @@ def test_chat_completion_request_n_parameter_exceeds_default_limit():
         )
 
 
-def test_chat_completion_request_n_parameter_at_limit():
+def test_chat_completion_request_n_parameter_at_limit(
+    monkeypatch: pytest.MonkeyPatch,
+):
     """Test that n at exactly the limit is accepted."""
     import vllm.envs as envs
 
+    monkeypatch.delenv("VLLM_MAX_N_SEQUENCES", raising=False)
+    if hasattr(envs.__getattr__, "cache_clear"):
+        envs.__getattr__.cache_clear()
+
     max_n = envs.VLLM_MAX_N_SEQUENCES
     request = ChatCompletionRequest(
         model="test-model",
@@ -1064,7 +1076,11 @@ def test_chat_completion_request_n_parameter_custom_limit(
     monkeypatch: pytest.MonkeyPatch,
 ):
     """Test that VLLM_MAX_N_SEQUENCES env var overrides the default limit."""
+    import vllm.envs as envs
+
     monkeypatch.setenv("VLLM_MAX_N_SEQUENCES", "128")
+    if hasattr(envs.__getattr__, "cache_clear"):
+        envs.__getattr__.cache_clear()
 
     request = ChatCompletionRequest(
         model="test-model",
@@ -1093,8 +1109,16 @@ def test_chat_completion_request_n_parameter_custom_limit(
         )
 
 
-def test_chat_completion_request_n_parameter_massive_value():
+def test_chat_completion_request_n_parameter_massive_value(
+    monkeypatch: pytest.MonkeyPatch,
+):
     """Test that astronomically large n values are rejected (CVE fix)."""
+    import vllm.envs as envs
+
+    monkeypatch.delenv("VLLM_MAX_N_SEQUENCES", raising=False)
+    if hasattr(envs.__getattr__, "cache_clear"):
+        envs.__getattr__.cache_clear()
+
     request = ChatCompletionRequest(
         model="test-model",
         messages=[{"role": "user", "content": "Test"}],

tests/test_envs.py

@@ -475,10 +475,16 @@ def test_custom_value(self, monkeypatch: pytest.MonkeyPatch):
 
         assert envs.VLLM_MAX_N_SEQUENCES == 128
 
-    def test_sampling_params_respects_limit(self):
+    def test_sampling_params_respects_limit(
+        self, monkeypatch: pytest.MonkeyPatch,
+    ):
         """Test that SamplingParams rejects n above the limit."""
         from vllm.sampling_params import SamplingParams
 
+        monkeypatch.delenv("VLLM_MAX_N_SEQUENCES", raising=False)
+        if hasattr(envs.__getattr__, "cache_clear"):
+            envs.__getattr__.cache_clear()
+
         max_n = envs.VLLM_MAX_N_SEQUENCES
         SamplingParams(n=max_n)