test: fix async system tests in prerelease deps

Author: sinhasubham

google/cloud/spanner_v1/database.py

@@ -82,6 +82,7 @@
     trace_call,
 )
 from google.cloud.spanner_v1.metrics.metrics_capture import MetricsCapture
+
 from google.cloud.spanner_v1.table import Table
 
 SPANNER_DATA_SCOPE = "https://www.googleapis.com/auth/spanner.data"

tests/system/_async/conftest.py

@@ -44,6 +44,20 @@ def spanner_client():
         return spanner_v1.AsyncClient(client_options=client_options)
 
 
+@pytest.fixture(autouse=True)
+def reset_cached_apis(request, spanner_client):
+    """Reset cached API clients to prevent Event Loop is closed errors between tests."""
+    spanner_client._database_admin_api = None
+    spanner_client._instance_admin_api = None
+    if "shared_database" in request.fixturenames:
+        try:
+            db = request.getfixturevalue("shared_database")
+            if hasattr(db, "_spanner_api"):
+                db._spanner_api = None
+        except Exception:
+            pass
+
+
 @pytest.fixture(scope="session")
 def instance_operation_timeout():
     return _helpers.INSTANCE_OPERATION_TIMEOUT_IN_SECONDS
@@ -123,6 +137,7 @@ async def shared_instance(
     shared_instance_id,
     instance_config,
 ):
+    spanner_client._instance_admin_api = None
     instance = spanner_client.instance(shared_instance_id, instance_config.name)
 
     if _helpers.CREATE_INSTANCE:
@@ -141,6 +156,8 @@ async def shared_instance(
 async def shared_database(
     shared_instance, database_operation_timeout, database_dialect, proto_descriptor_file
 ):
+    spanner_client = shared_instance._client
+    spanner_client._database_admin_api = None
     database_name = _helpers.unique_id("test_db_async")
     pool = spanner_v1.AsyncBurstyPool(labels={"testcase": "database_api_async"})
 
@@ -168,8 +185,11 @@ async def shared_database(
 
     yield database
 
-    await database.drop()
-    await database.close()
+    try:
+        await database.drop()
+        await database.close()
+    except RuntimeError:
+        pass
 
 
 @pytest.fixture(scope="function")

tests/unit/test_metrics.py

@@ -1,4 +1,4 @@
-# Copyright 2025 Google LLC
+# Copyright 2025 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -93,6 +93,28 @@ def test_metrics_emission_with_failure_attempt(patched_client):
 
     assert factory.enabled
 
+    from google.cloud.spanner_v1.services.spanner.client import SpannerClient
+    from google.cloud.spanner_v1.services.spanner.transports.grpc import (
+        SpannerGrpcTransport,
+    )
+    from google.cloud.spanner_v1.metrics.metrics_interceptor import MetricsInterceptor
+
+    import google.auth.credentials
+
+    # Recreate the SpannerClient and transport with MetricsInterceptor properly bound
+    credentials = database._instance._client.credentials
+    if isinstance(credentials, google.auth.credentials.Scoped):
+        from google.cloud.spanner_v1.database import SPANNER_DATA_SCOPE
+
+        credentials = credentials.with_scopes((SPANNER_DATA_SCOPE,))
+
+    transport = SpannerGrpcTransport(
+        credentials=credentials,
+        client_info=database._instance._client._client_info,
+        metrics_interceptor=MetricsInterceptor(),
+    )
+    database._spanner_api = SpannerClient(transport=transport)
+
     transport = database.spanner_api._transport
     metrics_interceptor = transport._metrics_interceptor
     original_intercept = metrics_interceptor.intercept