core: fix attributeerror in runnablelambda.deps (#20569)

- would happen when user's code tries to access attritbute that doesnt
exist, we prefer to let this crash in the user's code, rather than here
- also catch more cases where a runnable is invoked/streamed inside a
lambda. before we weren't seeing these as deps

libs/core/langchain_core/runnables/base.py

@@ -3752,7 +3752,13 @@ class RunnableLambda(Runnable[Input, Output]):
         else:
             objects = []
 
-        return [obj for obj in objects if isinstance(obj, Runnable)]
+        deps: List[Runnable] = []
+        for obj in objects:
+            if isinstance(obj, Runnable):
+                deps.append(obj)
+            elif isinstance(getattr(obj, "__self__", None), Runnable):
+                deps.append(obj.__self__)
+        return deps
 
     @property
     def config_specs(self) -> List[ConfigurableFieldSpec]:

libs/core/langchain_core/runnables/utils.py

@@ -263,7 +263,10 @@ def get_function_nonlocals(func: Callable) -> List[Any]:
                         if vv is None:
                             break
                         else:
-                            vv = getattr(vv, part)
+                            try:
+                                vv = getattr(vv, part)
+                            except AttributeError:
+                                break
                     else:
                         values.append(vv)
         return values

libs/core/tests/unit_tests/runnables/test_utils.py

@@ -1,9 +1,11 @@
 import sys
-from typing import Callable
+from typing import Callable, Dict
 
 import pytest
 
+from langchain_core.runnables.base import RunnableLambda
 from langchain_core.runnables.utils import (
+    get_function_nonlocals,
     get_lambda_source,
     indent_lines_after_first,
 )
@@ -37,3 +39,21 @@ def test_indent_lines_after_first(text: str, prefix: str, expected_output: str)
     """Test indent_lines_after_first function"""
     indented_text = indent_lines_after_first(text, prefix)
     assert indented_text == expected_output
+
+
+def test_nonlocals() -> None:
+    agent = RunnableLambda(lambda x: x * 2)  # noqa: F841
+
+    def my_func(input: str, agent: Dict[str, str]) -> str:
+        return agent.get("agent_name", input)
+
+    def my_func2(input: str) -> str:
+        return agent.get("agent_name", input)  # type: ignore[attr-defined]
+
+    def my_func3(input: str) -> str:
+        return agent.invoke(input)
+
+    assert get_function_nonlocals(my_func) == []
+    assert get_function_nonlocals(my_func2) == []
+    assert get_function_nonlocals(my_func3) == [agent.invoke]
+    assert RunnableLambda(my_func3).deps == [agent]