fixup: code style and convention alignment

- hoist a2a_push_config_store init outside per-agent loop, matching
  the task_store pattern (both now use if-None guard at the top)
- remove redundant local push_config_store variable; use
  a2a_push_config_store directly in DefaultRequestHandler call
- trim docstring: drop inline Example block, shorten to match the
  one-liner style used by the other params in the same function
- rename test to test_a2a_custom_task_store_is_used (shorter, matches
  existing naming style)
- fix test mock setup to use an explicit mock_a2a_app_instance like
  the test_app_with_a2a fixture does
- simplify test assertion: drop intermediate call_kwargs variable

Author: STHITAPRAJNAS

src/google/adk/cli/fast_api.py

@@ -128,22 +128,11 @@ def get_fast_api_app(
     web: Whether to enable the web UI and serve its assets.
     a2a: Whether to enable Agent-to-Agent (A2A) protocol support.
     a2a_task_store: Optional A2A TaskStore instance. Defaults to
-      InMemoryTaskStore when a2a=True. Pass a DatabaseTaskStore (from the
-      a2a-sdk) for persistence across server restarts and horizontal replicas.
-      Example::
-
-          from a2a.server.tasks import DatabaseTaskStore
-          from sqlalchemy.ext.asyncio import create_async_engine
-
-          engine = create_async_engine("postgresql+asyncpg://user:pw@host/db")
-          app = get_fast_api_app(
-              agents_dir="agents/", web=True, a2a=True,
-              a2a_task_store=DatabaseTaskStore(engine),
-          )
-
-    a2a_push_config_store: Optional A2A PushNotificationConfigStore instance.
-      Defaults to InMemoryPushNotificationConfigStore when a2a=True. Pass a
-      DatabasePushNotificationConfigStore for persistence across restarts.
+      InMemoryTaskStore. Pass a custom store (e.g. DatabaseTaskStore) to
+      persist task state across restarts or share it across replicas.
+    a2a_push_config_store: Optional A2A PushNotificationConfigStore.
+      Defaults to InMemoryPushNotificationConfigStore. Pass a custom store
+      for persistence across restarts.
     host: Host address for the server (defaults to 127.0.0.1).
     port: Port number for the server (defaults to 8000).
     url_prefix: Optional prefix for all URL routes.
@@ -582,6 +571,8 @@ async def get_agent_builder(
     if base_path.exists() and base_path.is_dir():
       if a2a_task_store is None:
         a2a_task_store = InMemoryTaskStore()
+      if a2a_push_config_store is None:
+        a2a_push_config_store = InMemoryPushNotificationConfigStore()
 
       def create_a2a_runner_loader(captured_app_name: str):
         """Factory function to create A2A runner with proper closure."""
@@ -609,16 +600,10 @@ async def _get_a2a_runner_async() -> Runner:
               runner=create_a2a_runner_loader(app_name),
           )
 
-          push_config_store = (
-              a2a_push_config_store
-              if a2a_push_config_store is not None
-              else InMemoryPushNotificationConfigStore()
-          )
-
           request_handler = DefaultRequestHandler(
               agent_executor=agent_executor,
               task_store=a2a_task_store,
-              push_config_store=push_config_store,
+              push_config_store=a2a_push_config_store,
           )
 
           with (p / "agent.json").open("r", encoding="utf-8") as f:

tests/unittests/cli/test_fast_api.py

@@ -1557,7 +1557,7 @@ def test_a2a_uses_in_memory_task_store_by_default(
     temp_agents_dir_with_a2a,
     monkeypatch,
 ):
-  """Test that InMemoryTaskStore is created when no task_store is provided."""
+  """Test that InMemoryTaskStore is used when no task store is provided."""
   with (
       patch("signal.signal", return_value=None),
       patch(
@@ -1590,7 +1590,9 @@ def test_a2a_uses_in_memory_task_store_by_default(
       patch("a2a.server.request_handlers.DefaultRequestHandler"),
       patch("a2a.server.apps.A2AStarletteApplication") as mock_a2a_app,
   ):
-    mock_a2a_app.return_value.routes.return_value = []
+    mock_a2a_app_instance = MagicMock()
+    mock_a2a_app_instance.routes.return_value = []
+    mock_a2a_app.return_value = mock_a2a_app_instance
     monkeypatch.chdir(temp_agents_dir_with_a2a)
 
     _ = get_fast_api_app(
@@ -1608,7 +1610,7 @@ def test_a2a_uses_in_memory_task_store_by_default(
     mock_task_store_class.assert_called_once()
 
 
-def test_a2a_custom_task_store_bypasses_in_memory_default(
+def test_a2a_custom_task_store_is_used(
     mock_session_service,
     mock_artifact_service,
     mock_memory_service,
@@ -1618,7 +1620,7 @@ def test_a2a_custom_task_store_bypasses_in_memory_default(
     temp_agents_dir_with_a2a,
     monkeypatch,
 ):
-  """Test that a custom task_store is forwarded and InMemoryTaskStore is not created."""
+  """Test that a custom task store is forwarded to DefaultRequestHandler."""
   custom_task_store = MagicMock()
 
   with (
@@ -1655,7 +1657,9 @@ def test_a2a_custom_task_store_bypasses_in_memory_default(
       ) as mock_handler,
       patch("a2a.server.apps.A2AStarletteApplication") as mock_a2a_app,
   ):
-    mock_a2a_app.return_value.routes.return_value = []
+    mock_a2a_app_instance = MagicMock()
+    mock_a2a_app_instance.routes.return_value = []
+    mock_a2a_app.return_value = mock_a2a_app_instance
     monkeypatch.chdir(temp_agents_dir_with_a2a)
 
     _ = get_fast_api_app(
@@ -1671,12 +1675,8 @@ def test_a2a_custom_task_store_bypasses_in_memory_default(
         port=8000,
     )
 
-    # InMemoryTaskStore must NOT be instantiated when a custom store is supplied
     mock_task_store_class.assert_not_called()
-
-    # The custom store must be passed through to DefaultRequestHandler
-    call_kwargs = mock_handler.call_args.kwargs
-    assert call_kwargs["task_store"] is custom_task_store
+    assert mock_handler.call_args.kwargs["task_store"] is custom_task_store
 
 
 def test_patch_memory(test_app, create_test_session, mock_memory_service):