chore: import upstream snapshot with attribution

tests/unittests/workflow/test_agent_node.py

@@ -0,0 +1,71 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Unit tests for BaseAgent acting as a workflow node."""
+
+from __future__ import annotations
+
+from typing import AsyncGenerator
+
+from google.adk.agents.base_agent import BaseAgent
+from google.adk.agents.context import Context
+from google.adk.agents.invocation_context import InvocationContext
+from google.adk.events.event import Event
+from google.adk.sessions.in_memory_session_service import InMemorySessionService
+from google.adk.sessions.session import Session
+import pytest
+
+
+class MockAgent(BaseAgent):
+  """A mock agent that yields predefined events."""
+
+  async def _run_async_impl(
+      self, ctx: InvocationContext
+  ) -> AsyncGenerator[Event, None]:
+    yield Event(author=self.name)
+    yield Event(author="sub_agent")
+
+
+@pytest.mark.asyncio
+async def test_base_agent_as_node_run():
+  """Tests that BaseAgent runs as a node and preserves event authors."""
+  agent = MockAgent(name="mock_agent")
+
+  # Setup minimal context
+  session = Session(app_name="test", user_id="user", id="session")
+  session_service = InMemorySessionService()
+  ic = InvocationContext(
+      invocation_id="inv",
+      session=session,
+      session_service=session_service,
+  )
+  ctx = Context(ic, node_path="wf")
+
+  events = []
+  async for event in agent.run(ctx=ctx, node_input=None):
+    events.append(event)
+
+  assert len(events) == 2
+
+  # First event from mock_agent
+  assert events[0].author == "mock_agent"
+  assert events[0].node_info.path == "wf"
+
+  # Second event from sub_agent
+  assert events[1].author == "sub_agent"
+  # Path should not be set by BaseAgent for sub_agent if author doesn't match agent name
+  assert not events[1].node_info.path
+
+  # Also check if ctx.event_author was updated to preserve author for NodeRunner
+  assert ctx.event_author == "sub_agent"