ToolsTests Class — langchain Architecture

Source Code

libs/standard-tests/langchain_tests/unit_tests/tools.py lines 17–55

class ToolsTests(BaseStandardTests):
    """Base class for testing tools.

    This won't show in the documentation, but the docstrings will be inherited by
    subclasses.
    """

    @property
    @abstractmethod
    def tool_constructor(self) -> type[BaseTool] | BaseTool:
        """Returns a class or instance of a tool to be tested."""
        ...

    @property
    def tool_constructor_params(self) -> dict[str, Any]:
        """Returns a dictionary of parameters to pass to the tool constructor."""
        return {}

    @property
    def tool_invoke_params_example(self) -> dict[str, Any]:
        """Returns a dictionary representing the "args" of an example tool call.

        This should NOT be a `ToolCall` dict - it should not have
        `{"name", "id", "args"}` keys.
        """
        return {}

    @pytest.fixture
    def tool(self) -> BaseTool:
        """Tool fixture."""
        if isinstance(self.tool_constructor, BaseTool):
            if self.tool_constructor_params != {}:
                msg = (
                    "If tool_constructor is an instance of BaseTool, "
                    "tool_constructor_params must be empty"
                )
                raise ValueError(msg)
            return self.tool_constructor
        return self.tool_constructor(**self.tool_constructor_params)