chore: import upstream snapshot with attribution

tests/unittests/integrations/langchain/test_langchain_tool.py

@@ -0,0 +1,101 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from unittest.mock import MagicMock
+
+from google.adk.integrations.langchain import LangchainTool
+from langchain_core.tools import tool
+from langchain_core.tools.structured import StructuredTool
+from pydantic import BaseModel
+import pytest
+
+
+@tool
+async def async_add_with_annotation(x, y) -> int:
+  """Adds two numbers"""
+  return x + y
+
+
+@tool
+def sync_add_with_annotation(x, y) -> int:
+  """Adds two numbers"""
+  return x + y
+
+
+async def async_add(x, y) -> int:
+  return x + y
+
+
+def sync_add(x, y) -> int:
+  return x + y
+
+
+class AddSchema(BaseModel):
+  x: int
+  y: int
+
+
+test_langchain_async_add_tool = StructuredTool.from_function(
+    async_add,
+    name="add",
+    description="Adds two numbers",
+    args_schema=AddSchema,
+)
+
+test_langchain_sync_add_tool = StructuredTool.from_function(
+    sync_add,
+    name="add",
+    description="Adds two numbers",
+    args_schema=AddSchema,
+)
+
+
+@pytest.mark.asyncio
+async def test_raw_async_function_works():
+  """Test that passing a raw async function to LangchainTool works correctly."""
+  langchain_tool = LangchainTool(tool=test_langchain_async_add_tool)
+  result = await langchain_tool.run_async(
+      args={"x": 1, "y": 3}, tool_context=MagicMock()
+  )
+  assert result == 4
+
+
+@pytest.mark.asyncio
+async def test_raw_sync_function_works():
+  """Test that passing a raw sync function to LangchainTool works correctly."""
+  langchain_tool = LangchainTool(tool=test_langchain_sync_add_tool)
+  result = await langchain_tool.run_async(
+      args={"x": 1, "y": 3}, tool_context=MagicMock()
+  )
+  assert result == 4
+
+
+@pytest.mark.asyncio
+async def test_raw_async_function_with_annotation_works():
+  """Test that passing a raw async function to LangchainTool works correctly."""
+  langchain_tool = LangchainTool(tool=async_add_with_annotation)
+  result = await langchain_tool.run_async(
+      args={"x": 1, "y": 3}, tool_context=MagicMock()
+  )
+  assert result == 4
+
+
+@pytest.mark.asyncio
+async def test_raw_sync_function_with_annotation_works():
+  """Test that passing a raw sync function to LangchainTool works correctly."""
+  langchain_tool = LangchainTool(tool=sync_add_with_annotation)
+  result = await langchain_tool.run_async(
+      args={"x": 1, "y": 3}, tool_context=MagicMock()
+  )
+  assert result == 4