test_chat_prompt_template_message_class_tuples_with_invoke() — langchain Function Reference

Source Code

libs/core/tests/unit_tests/prompts/test_chat.py lines 341–357

def test_chat_prompt_template_message_class_tuples_with_invoke() -> None:
    """Test message class tuples work with invoke() method."""
    template = ChatPromptTemplate.from_messages(
        [
            (SystemMessage, "You are {name}."),
            (HumanMessage, "{question}"),
        ]
    )

    result = template.invoke({"name": "Alice", "question": "Hello?"})
    messages = result.to_messages()

    assert len(messages) == 2
    assert isinstance(messages[0], SystemMessage)
    assert isinstance(messages[1], HumanMessage)
    assert messages[0].content == "You are Alice."
    assert messages[1].content == "Hello?"