test_middleware_end_behavior_with_unrelated_parallel_tool_calls() — langchain Function Reference

Source Code

libs/langchain_v1/tests/unit_tests/agents/middleware/implementations/test_tool_call_limit.py lines 161–193

def test_middleware_end_behavior_with_unrelated_parallel_tool_calls() -> None:
    """Test middleware 'end' behavior with unrelated parallel tool calls.

    Test that 'end' behavior raises NotImplementedError when there are parallel calls
    to unrelated tools.

    When limiting a specific tool with "end" behavior and the model proposes parallel calls
    to BOTH the limited tool AND other tools, we can't handle this scenario (we'd be stopping
    execution while other tools should run).
    """
    # Limit search tool specifically
    middleware = ToolCallLimitMiddleware(tool_name="search", thread_limit=1, exit_behavior="end")
    runtime = None

    # Test with search + calculator calls when search exceeds limit
    state = ToolCallLimitState(
        messages=[
            AIMessage(
                "Response",
                tool_calls=[
                    {"name": "search", "args": {}, "id": "1"},
                    {"name": "calculator", "args": {}, "id": "2"},
                ],
            ),
        ],
        thread_tool_call_count={"search": 1},
        run_tool_call_count={"search": 1},
    )

    with pytest.raises(
        NotImplementedError, match="Cannot end execution with other tool calls pending"
    ):
        middleware.after_model(state, runtime)  # type: ignore[arg-type]