test_todo_middleware_agent_creation_with_middleware() — langchain Function Reference

Source Code

libs/langchain_v1/tests/unit_tests/agents/middleware/implementations/test_todo.py lines 368–413

def test_todo_middleware_agent_creation_with_middleware() -> None:
    """Test that an agent can be created with the planning middleware."""
    model = FakeToolCallingModel(
        tool_calls=[
            [
                {
                    "args": {"todos": [{"content": "Task 1", "status": "pending"}]},
                    "name": "write_todos",
                    "type": "tool_call",
                    "id": "test_call",
                }
            ],
            [
                {
                    "args": {"todos": [{"content": "Task 1", "status": "in_progress"}]},
                    "name": "write_todos",
                    "type": "tool_call",
                    "id": "test_call",
                }
            ],
            [
                {
                    "args": {"todos": [{"content": "Task 1", "status": "completed"}]},
                    "name": "write_todos",
                    "type": "tool_call",
                    "id": "test_call",
                }
            ],
            [],
        ]
    )
    middleware = TodoListMiddleware()
    agent = create_agent(model=model, middleware=[middleware])

    result = agent.invoke({"messages": [HumanMessage("Hello")]})
    assert result["todos"] == [{"content": "Task 1", "status": "completed"}]

    # human message (1)
    # ai message (2) - initial todo
    # tool message (3)
    # ai message (4) - updated todo
    # tool message (5)
    # ai message (6) - complete todo
    # tool message (7)
    # ai message (8) - no tool calls
    assert len(result["messages"]) == 8