Handle synchronous generator functions in _invoke_callable

Author: ItsMacto

src/google/adk/tools/function_tool.py

@@ -230,6 +230,13 @@ async def _invoke_callable(
     if is_async_gen:
       return [item async for item in target(**args_to_call)]
 
+    is_sync_gen = inspect.isgeneratorfunction(target) or (
+        hasattr(target, '__call__')
+        and inspect.isgeneratorfunction(target.__call__)
+    )
+    if is_sync_gen:
+      return list(target(**args_to_call))
+
     # Functions are callable objects, but not all callable objects are functions
     # checking coroutine function is not enough. We also need to check whether
     # Callable's __call__ function is a coroutine function

tests/unittests/tools/test_function_tool.py

@@ -14,6 +14,7 @@
 
 import collections.abc
 from typing import AsyncGenerator
+from typing import Generator
 from unittest.mock import MagicMock
 
 from google.adk.agents.invocation_context import InvocationContext
@@ -458,3 +459,19 @@ async def streaming_tool(param: str) -> AsyncGenerator[str, None]:
 
   assert isinstance(result, list)
   assert result == ["part 1 test", "part 2 test"]
+
+
+@pytest.mark.asyncio
+async def test_run_async_sync_generator():
+  """Test that run_async consumes the sync generator and returns a list."""
+
+  def sync_generator_tool(param: str) -> Generator[str, None, None]:
+    yield f"part 1 {param}"
+    yield f"part 2 {param}"
+
+  tool = FunctionTool(sync_generator_tool)
+
+  result = await tool.run_async(args={"param": "test"}, tool_context=None)
+
+  assert isinstance(result, list)
+  assert result == ["part 1 test", "part 2 test"]