test_model_retry_failing_model_raises() — langchain Function Reference

Source Code

libs/langchain_v1/tests/unit_tests/agents/middleware/implementations/test_model_retry.py lines 203–226

def test_model_retry_failing_model_raises() -> None:
    """Test ModelRetryMiddleware with on_failure='error' re-raises exception."""
    model = AlwaysFailingModel(error_message="Model error", error_type=ValueError)

    retry = ModelRetryMiddleware(
        max_retries=2,
        initial_delay=0.01,
        jitter=False,
        on_failure="error",
    )

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

    # Should raise the ValueError from the model
    with pytest.raises(ValueError, match="Model error"):
        agent.invoke(
            {"messages": [HumanMessage("Hello")]},
            {"configurable": {"thread_id": "test"}},
        )