From afa9d1292b0a152e36d338dde7b02f0b93bd37d9 Mon Sep 17 00:00:00 2001
From: Zander Chase <130414180+vowelparrot@users.noreply.github.com>
Date: Wed, 3 May 2023 13:16:41 -0700
Subject: [PATCH] Re-Permit Partials in `Tool` (#4058)

Resolved issue #4053

Now that StructuredTool is a separate class, this constraint is no
longer needed.

Added/updated a unit test
---
 langchain/tools/base.py               |  9 ---------
 tests/unit_tests/agents/test_tools.py | 15 ++++++---------
 2 files changed, 6 insertions(+), 18 deletions(-)

diff --git a/langchain/tools/base.py b/langchain/tools/base.py
index f231b5ef..5bbbf405 100644
--- a/langchain/tools/base.py
+++ b/langchain/tools/base.py
@@ -3,7 +3,6 @@ from __future__ import annotations
 
 import warnings
 from abc import ABC, abstractmethod
-from functools import partial
 from inspect import signature
 from typing import Any, Awaitable, Callable, Dict, Optional, Tuple, Type, Union
 
@@ -14,7 +13,6 @@ from pydantic import (
     create_model,
     root_validator,
     validate_arguments,
-    validator,
 )
 from pydantic.main import ModelMetaclass
 
@@ -309,13 +307,6 @@ class Tool(BaseTool):
     coroutine: Optional[Callable[..., Awaitable[str]]] = None
     """The asynchronous version of the function."""
 
-    @validator("func", pre=True, always=True)
-    def validate_func_not_partial(cls, func: Callable) -> Callable:
-        """Check that the function is not a partial."""
-        if isinstance(func, partial):
-            raise ValueError("Partial functions not yet supported in tools.")
-        return func
-
     @property
     def args(self) -> dict:
         """The tool's input arguments."""
diff --git a/tests/unit_tests/agents/test_tools.py b/tests/unit_tests/agents/test_tools.py
index 094774fb..8001e5c8 100644
--- a/tests/unit_tests/agents/test_tools.py
+++ b/tests/unit_tests/agents/test_tools.py
@@ -4,7 +4,6 @@ from functools import partial
 from typing import Any, Optional, Type, Union
 from unittest.mock import MagicMock
 
-import pydantic
 import pytest
 from pydantic import BaseModel
 
@@ -252,14 +251,12 @@ def test_tool_partial_function_args_schema() -> None:
     def func(tool_input: str, other_arg: str) -> str:
         return tool_input + other_arg
 
-    with pytest.raises(pydantic.error_wrappers.ValidationError):
-        # We don't yet support args_schema inference for partial functions
-        # so want to make sure we proactively raise an error
-        Tool(
-            name="tool",
-            description="A tool",
-            func=partial(func, other_arg="foo"),
-        )
+    tool = Tool(
+        name="tool",
+        description="A tool",
+        func=partial(func, other_arg="foo"),
+    )
+    assert tool.run("bar") == "barfoo"
 
 
 def test_empty_args_decorator() -> None: