test(tools): cover sync-func-returning-coroutine branch; clarify run_coroutine_sync docstring

Author: Shailendra005

lib/crewai/src/crewai/utilities/async_utils.py

@@ -16,9 +16,11 @@ def run_coroutine_sync(coro: Coroutine[Any, Any, T]) -> T:
     When called from within a running event loop (for example a FastAPI
     request handler, a Jupyter cell or any ``async def``), ``asyncio.run``
     raises ``RuntimeError: asyncio.run() cannot be called from a running event
-    loop``. In that case the coroutine is executed to completion in a
-    dedicated worker thread so the calling loop is neither blocked nor
-    re-entered. Otherwise it falls back to ``asyncio.run``.
+    loop``. In that case the coroutine is executed to completion on a
+    dedicated worker thread (with a copy of the current context), which avoids
+    re-entering the running loop. The calling thread blocks on
+    ``Future.result()`` until the coroutine finishes, so the running loop makes
+    no progress while it waits. Otherwise it falls back to ``asyncio.run``.
     """
     try:
         asyncio.get_running_loop()

lib/crewai/tests/tools/test_async_tools.py

@@ -202,6 +202,31 @@ async def caller() -> str:
         result = asyncio.run(caller())
         assert result == "structured: test"
 
+    def test_structured_tool_invoke_returned_coroutine_inside_running_loop(
+        self,
+    ) -> None:
+        """CrewStructuredTool.invoke() must resolve a coroutine returned by a
+        sync func under a running loop (the non-``async def`` branch)."""
+
+        def sync_returns_coro(value: str) -> str:
+            """A sync structured tool that returns a coroutine."""
+
+            async def _inner() -> str:
+                await asyncio.sleep(0.01)
+                return f"returned: {value}"
+
+            return _inner()  # type: ignore[return-value]
+
+        structured = CrewStructuredTool.from_function(
+            func=sync_returns_coro, name="structured_returns_coro"
+        )
+
+        async def caller() -> str:
+            return structured.invoke({"value": "test"})
+
+        result = asyncio.run(caller())
+        assert result == "returned: test"
+
 
 class TestAsyncToolWithIO:
     """Tests for async tools with simulated I/O operations."""