langchain/tests/unit_tests/agents/test_tools.py

"""Test tool utils."""
import pytest

from langchain.agents.tools import Tool, tool


def test_unnamed_decorator() -> None:
    """Test functionality with unnamed decorator."""

    @tool
    def search_api(query: str) -> str:
        """Search the API for the query."""
        return "API result"

    assert isinstance(search_api, Tool)
    assert search_api.name == "search_api"
    assert not search_api.return_direct
    assert search_api("test") == "API result"


def test_named_tool_decorator() -> None:
    """Test functionality when arguments are provided as input to decorator."""

    @tool("search")
    def search_api(query: str) -> str:
        """Search the API for the query."""
        return "API result"

    assert isinstance(search_api, Tool)
    assert search_api.name == "search"
    assert not search_api.return_direct


def test_named_tool_decorator_return_direct() -> None:
    """Test functionality when arguments and return direct are provided as input."""

    @tool("search", return_direct=True)
    def search_api(query: str) -> str:
        """Search the API for the query."""
        return "API result"

    assert isinstance(search_api, Tool)
    assert search_api.name == "search"
    assert search_api.return_direct


def test_unnamed_tool_decorator_return_direct() -> None:
    """Test functionality when only return direct is provided."""

    @tool(return_direct=True)
    def search_api(query: str) -> str:
        """Search the API for the query."""
        return "API result"

    assert isinstance(search_api, Tool)
    assert search_api.name == "search_api"
    assert search_api.return_direct


def test_missing_docstring() -> None:
    """Test error is raised when docstring is missing."""
    # expect to throw a value error if theres no docstring
    with pytest.raises(AssertionError):

        @tool
        def search_api(query: str) -> str:
            return "API result"


def test_create_tool_posistional_args() -> None:
    """Test that positional arguments are allowed."""
    test_tool = Tool("test_name", lambda x: x, "test_description")
    assert test_tool("foo") == "foo"
    assert test_tool.name == "test_name"
    assert test_tool.description == "test_description"


def test_create_tool_keyword_args() -> None:
    """Test that keyword arguments are allowed."""
    test_tool = Tool(name="test_name", func=lambda x: x, description="test_description")
    assert test_tool("foo") == "foo"
    assert test_tool.name == "test_name"
    assert test_tool.description == "test_description"


@pytest.mark.asyncio
async def test_create_async_tool() -> None:
    """Test that async tools are allowed."""

    async def _test_func(x: str) -> str:
        return x

    test_tool = Tool(
        name="test_name",
        func=lambda x: x,
        description="test_description",
        coroutine=_test_func,
    )
    assert test_tool("foo") == "foo"
    assert test_tool.name == "test_name"
    assert test_tool.description == "test_description"
    assert test_tool.coroutine is not None
    assert await test_tool.arun("foo") == "foo"