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"""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"