format

libs/core/langchain_core/callbacks/manager.py

@@ -238,10 +238,10 @@ def shielded(func: Func) -> Func:
     async def wrapped(*args: Any, **kwargs: Any) -> Any:
         # Capture the current context to preserve context variables
         ctx = copy_context()
-        
+
         # Create the coroutine
         coro = func(*args, **kwargs)
-        
+
         # For Python 3.11+, create task with explicit context
         # For older versions, fallback to original behavior
         try:

libs/core/tests/unit_tests/callbacks/test_async_callback_manager.py

@@ -153,56 +153,56 @@ async def test_inline_handlers_share_parent_context_multiple() -> None:
 
 async def test_shielded_callback_context_preservation() -> None:
     """Verify that shielded callbacks preserve context variables.
-    
+
     This test specifically addresses the issue where async callbacks decorated
     with @shielded do not properly preserve context variables, breaking
     instrumentation and other context-dependent functionality.
-    
+
     The issue manifests in callbacks that use the @shielded decorator:
     * on_llm_end
-    * on_llm_error 
+    * on_llm_error
     * on_chain_end
     * on_chain_error
     * And other shielded callback methods
     """
     context_var: contextvars.ContextVar[str] = contextvars.ContextVar("test_context")
-    
+
     class ContextTestHandler(AsyncCallbackHandler):
         """Handler that reads context variables in shielded callbacks."""
-        
+
         def __init__(self) -> None:
             self.run_inline = False
             self.context_values = []
-    
-        @override  
+
+        @override
         async def on_llm_end(self, response: Any, **kwargs: Any) -> None:
             """This method is decorated with @shielded in the run manager."""
             # This should preserve the context variable value
             self.context_values.append(context_var.get("not_found"))
-            
+
         @override
         async def on_chain_end(self, outputs: Any, **kwargs: Any) -> None:
             """This method is decorated with @shielded in the run manager."""
             # This should preserve the context variable value
             self.context_values.append(context_var.get("not_found"))
-    
+
     # Set up the test context
     context_var.set("test_value")
     handler = ContextTestHandler()
     manager = AsyncCallbackManager(handlers=[handler])
-    
+
     # Create run managers that have the shielded methods
     llm_managers = await manager.on_llm_start({}, ["test prompt"])
     llm_run_manager = llm_managers[0]
-    
+
     chain_run_manager = await manager.on_chain_start({}, {"test": "input"})
-    
+
     # Test LLM end callback (which is shielded)
     await llm_run_manager.on_llm_end({"response": "test"})
-    
-    # Test Chain end callback (which is shielded) 
+
+    # Test Chain end callback (which is shielded)
     await chain_run_manager.on_chain_end({"output": "test"})
-    
+
     # The context should be preserved in shielded callbacks
     # This was the main issue - shielded decorators were not preserving context
     assert handler.context_values == ["test_value", "test_value"], (