[ci][bugfix] fix kernel tests (#10431)

Signed-off-by: youkaichao <youkaichao@gmail.com>

vllm/plugins/__init__.py

@@ -6,9 +6,6 @@ import vllm.envs as envs
 
 if TYPE_CHECKING:
     from vllm.config import CompilationConfig, VllmConfig
-else:
-    CompilationConfig = None
-    VllmConfig = None
 
 logger = logging.getLogger(__name__)
 
@@ -50,23 +47,23 @@ def load_general_plugins():
                 logger.exception("Failed to load plugin %s", plugin.name)
 
 
-_compilation_config: Optional[CompilationConfig] = None
+_compilation_config: Optional["CompilationConfig"] = None
 
 
-def set_compilation_config(config: Optional[CompilationConfig]):
+def set_compilation_config(config: Optional["CompilationConfig"]):
     global _compilation_config
     _compilation_config = config
 
 
-def get_compilation_config() -> Optional[CompilationConfig]:
+def get_compilation_config() -> Optional["CompilationConfig"]:
     return _compilation_config
 
 
-_current_vllm_config: Optional[VllmConfig] = None
+_current_vllm_config: Optional["VllmConfig"] = None
 
 
 @contextmanager
-def set_current_vllm_config(vllm_config: VllmConfig):
+def set_current_vllm_config(vllm_config: "VllmConfig"):
     """
     Temporarily set the current VLLM config.
     Used during model initialization.
@@ -87,6 +84,12 @@ def set_current_vllm_config(vllm_config: VllmConfig):
         _current_vllm_config = old_vllm_config
 
 
-def get_current_vllm_config() -> VllmConfig:
-    assert _current_vllm_config is not None, "Current VLLM config is not set."
+def get_current_vllm_config() -> "VllmConfig":
+    if _current_vllm_config is None:
+        # in ci, usually when we test custom ops/modules directly,
+        # we don't set the vllm config. In that case, we set a default
+        # config.
+        logger.warning("Current VLLM config is not set.")
+        from vllm.config import VllmConfig
+        return VllmConfig()
     return _current_vllm_config