test_wrap_tool_call_logging() — langchain Function Reference

Source Code

libs/langchain_v1/tests/unit_tests/agents/middleware/core/test_wrap_tool_call.py lines 77–112

def test_wrap_tool_call_logging() -> None:
    """Test logging tool call execution with wrap_tool_call decorator."""
    call_log = []

    @wrap_tool_call
    def logging_middleware(
        request: ToolCallRequest, handler: Callable[[ToolCallRequest], ToolMessage | Command[Any]]
    ) -> ToolMessage | Command[Any]:
        assert isinstance(request.tool, BaseTool)
        call_log.append(f"before_{request.tool.name}")
        response = handler(request)
        call_log.append(f"after_{request.tool.name}")
        return response

    model = FakeToolCallingModel(
        tool_calls=[
            [ToolCall(name="search", args={"query": "test"}, id="1")],
            [],
        ]
    )

    agent = create_agent(
        model=model,
        tools=[search],
        middleware=[logging_middleware],
        checkpointer=InMemorySaver(),
    )

    result = agent.invoke(
        {"messages": [HumanMessage("Search")]},
        {"configurable": {"thread_id": "test"}},
    )

    assert call_log == ["before_search", "after_search"]
    tool_messages = [m for m in result["messages"] if isinstance(m, ToolMessage)]
    assert len(tool_messages) == 1