core: Include global variables in variables found by get_function_nonlocals (#25936)

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libs/core/Makefile

@@ -13,7 +13,7 @@ tests:
 	poetry run pytest $(TEST_FILE)
 
 test_watch:
-	poetry run ptw --snapshot-update --now . -- -vv tests/unit_tests
+	poetry run ptw --snapshot-update --now . -- -vv $(TEST_FILE)
 
 test_profile:
 	poetry run pytest -vv tests/unit_tests/ --profile-svg

libs/core/langchain_core/runnables/utils.py

@@ -393,7 +393,9 @@ def get_function_nonlocals(func: Callable) -> List[Any]:
         visitor = FunctionNonLocals()
         visitor.visit(tree)
         values: List[Any] = []
-        for k, v in inspect.getclosurevars(func).nonlocals.items():
+        closure = inspect.getclosurevars(func)
+        candidates = {**closure.globals, **closure.nonlocals}
+        for k, v in candidates.items():
             if k in visitor.nonlocals:
                 values.append(v)
             for kk in visitor.nonlocals:

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

@@ -1,5 +1,5 @@
 import sys
-from typing import Callable, Dict
+from typing import Callable, Dict, Tuple
 
 import pytest
 
@@ -41,6 +41,9 @@ def test_indent_lines_after_first(text: str, prefix: str, expected_output: str)
     assert indented_text == expected_output
 
 
+global_agent = RunnableLambda(lambda x: x * 3)
+
+
 def test_nonlocals() -> None:
     agent = RunnableLambda(lambda x: x * 2)
 
@@ -53,7 +56,23 @@ def test_nonlocals() -> None:
     def my_func3(input: str) -> str:
         return agent.invoke(input)
 
+    def my_func4(input: str) -> str:
+        return global_agent.invoke(input)
+
+    def my_func5() -> Tuple[Callable[[str], str], RunnableLambda]:
+        global_agent = RunnableLambda(lambda x: x * 3)
+
+        def my_func6(input: str) -> str:
+            return global_agent.invoke(input)
+
+        return my_func6, global_agent
+
     assert get_function_nonlocals(my_func) == []
     assert get_function_nonlocals(my_func2) == []
     assert get_function_nonlocals(my_func3) == [agent.invoke]
+    assert get_function_nonlocals(my_func4) == [global_agent.invoke]
+    func, nl = my_func5()
+    assert get_function_nonlocals(func) == [nl.invoke]
     assert RunnableLambda(my_func3).deps == [agent]
+    assert RunnableLambda(my_func4).deps == [global_agent]
+    assert RunnableLambda(func).deps == [nl]