fix(toolbox-core): Prevent rebinding of parameters in ToolboxTool (#186)

* fix(toolbox-core): Prevent rebinding of parameters in ToolboxTool

This pull request updates the `bind_parameters` helper function within the `ToolboxTool` of the `toolbox-core` package to enhance parameter binding management.

* The helper now throws an explicit error if a user attempts to bind a parameter that has already been bound. This change aims to prevent unexpected behavior and improve the clarity of parameter assignments.
* The error that previously occurred when a user tried to bind a parameter not present in the tool's schema has been removed. This validation will be handled by a `strict` mode implementation in a future PR.

* chore: Update unit test case

* chore: Delint

* fix: Add the no parameter check back again.

We will remove this once we actually implement the `strict` flag and centralize this functionality by moving this check to the tool's constructor in a future PR.

* fix: Reverse the error conditions to avoid masking of the second error.

* chore: Fix unit test cases.

* chore: Make unit test more robust.

* chore: Delint

Author: anubhav756

packages/toolbox-core/src/toolbox_core/tool.py

@@ -316,6 +316,11 @@ def bind_parameters(
         """
         param_names = set(p.name for p in self.__params)
         for name in bound_params.keys():
+            if name in self.__bound_parameters:
+                raise ValueError(
+                    f"cannot re-bind parameter: parameter '{name}' is already bound"
+                )
+
             if name not in param_names:
                 raise Exception(f"unable to bind parameters: no parameter named {name}")
 

packages/toolbox-core/tests/test_client.py

@@ -431,14 +431,38 @@ async def test_bind_callable_param_success(self, tool_name, client):
 
     @pytest.mark.asyncio
     async def test_bind_param_fail(self, tool_name, client):
-        """Tests 'bind_param' with a bound parameter that doesn't exist."""
+        """Tests 'bind_parameters' with a bound parameter that doesn't exist."""
         tool = await client.load_tool(tool_name)
 
         assert len(tool.__signature__.parameters) == 2
         assert "argA" in tool.__signature__.parameters
 
-        with pytest.raises(Exception):
-            tool = tool.bind_parameters({"argC": lambda: 5})
+        with pytest.raises(Exception) as e:
+            tool.bind_parameters({"argC": lambda: 5})
+        assert "unable to bind parameters: no parameter named argC" in str(e.value)
+
+    @pytest.mark.asyncio
+    async def test_rebind_param_fail(self, tool_name, client):
+        """
+        Tests that 'bind_parameters' fails when attempting to re-bind a
+        parameter that has already been bound.
+        """
+        tool = await client.load_tool(tool_name)
+
+        assert len(tool.__signature__.parameters) == 2
+        assert "argA" in tool.__signature__.parameters
+
+        tool_with_bound_param = tool.bind_parameters({"argA": lambda: 10})
+
+        assert len(tool_with_bound_param.__signature__.parameters) == 1
+        assert "argA" not in tool_with_bound_param.__signature__.parameters
+
+        with pytest.raises(ValueError) as e:
+            tool_with_bound_param.bind_parameters({"argA": lambda: 20})
+
+        assert "cannot re-bind parameter: parameter 'argA' is already bound" in str(
+            e.value
+        )
 
     @pytest.mark.asyncio
     async def test_bind_param_static_value_success(self, tool_name, client):