fix(iorails): avoid IORails sync generate coroutine warning

nemoguardrails/guardrails/iorails.py

@@ -269,6 +269,15 @@ def generate(self, messages: LLMMessages, **kwargs) -> LLMMessage:
         if sync_config.metrics is not None:
             sync_config.metrics.enabled = False
 
+        try:
+            asyncio.get_running_loop()
+        except RuntimeError:
+            pass
+        else:
+            raise RuntimeError(
+                "IORails.generate() cannot be called from a running event loop. Use generate_async() instead."
+            )
+
         async def _run_sync_iorails():
             """Spin up a short-lived IORails engine for one synchronous generate call."""
             # Avoid counting this sync-API bridge as a separate user-created IORails instance.

tests/guardrails/test_iorails.py

@@ -16,6 +16,8 @@
 """Unit tests for iorails module."""
 
 import asyncio
+import gc
+import warnings
 from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
@@ -685,8 +687,15 @@ def test_generate_raises_when_called_from_async_loop(self, iorails):
         async def call_generate():
             iorails.generate([{"role": "user", "content": "hi"}])
 
-        with pytest.raises(RuntimeError):
-            asyncio.run(call_generate())
+        with warnings.catch_warnings(record=True) as recorded_warnings:
+            warnings.simplefilter("always")
+
+            with pytest.raises(RuntimeError, match="cannot be called from a running event loop"):
+                asyncio.run(call_generate())
+
+            gc.collect()
+
+        assert not [warning for warning in recorded_warnings if issubclass(warning.category, RuntimeWarning)]
 
 
 class TestRefusalMessage: