[Core] Add an environment variable which needs to be set explicitly to allow BlockSpaceManagerV1 (#9149)

tests/prefix_caching/test_prefix_caching.py

@@ -7,6 +7,7 @@ from typing import List
 import pytest
 
 from tests.kernels.utils import override_backend_env_variable
+from tests.utils import check_deprecated_block_manager_usage
 from vllm.block import PhysicalTokenBlock
 from vllm.core.block_manager_v1 import CachedBlockAllocator
 from vllm.utils import Device
@@ -18,6 +19,12 @@ MODELS = [
 ]
 
 
+@pytest.fixture(scope="module", autouse=True)
+def check_deprecated_block_manager():
+    check_deprecated_block_manager_usage(
+        'tests/prefix_caching/test_prefix_caching.py')
+
+
 @pytest.mark.parametrize("block_size", [16])
 @pytest.mark.parametrize("num_blocks", [16])
 def test_block_allocator(