test: restore default event loop for sync tests

tests/conftest.py

@@ -1,5 +1,6 @@
 """Shared fixtures for the hermes-agent test suite."""
 
+import asyncio
 import os
 import signal
 import sys
@@ -59,6 +60,39 @@ def mock_config():
 def _timeout_handler(signum, frame):
     raise TimeoutError("Test exceeded 30 second timeout")
 
+@pytest.fixture(autouse=True)
+def _ensure_current_event_loop(request):
+    """Provide a default event loop for sync tests that call get_event_loop().
+
+    Python 3.11+ no longer guarantees a current loop for plain synchronous tests.
+    A number of gateway tests still use asyncio.get_event_loop().run_until_complete(...).
+    Ensure they always have a usable loop without interfering with pytest-asyncio's
+    own loop management for @pytest.mark.asyncio tests.
+    """
+    if request.node.get_closest_marker("asyncio") is not None:
+        yield
+        return
+
+    try:
+        loop = asyncio.get_event_loop_policy().get_event_loop()
+    except RuntimeError:
+        loop = None
+
+    created = loop is None or loop.is_closed()
+    if created:
+        loop = asyncio.new_event_loop()
+        asyncio.set_event_loop(loop)
+
+    try:
+        yield
+    finally:
+        if created and loop is not None:
+            try:
+                loop.close()
+            finally:
+                asyncio.set_event_loop(None)
+
+
 @pytest.fixture(autouse=True)
 def _enforce_test_timeout():
     """Kill any individual test that takes longer than 30 seconds."""