chore: import upstream snapshot with attribution

tests/unittests/plugins/test_multimodal_tool_results_plugin.py

@@ -0,0 +1,154 @@
+# 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 __future__ import annotations
+
+from typing import Any
+from unittest.mock import Mock
+
+from google.adk.agents.base_agent import BaseAgent
+from google.adk.agents.callback_context import CallbackContext
+from google.adk.models.llm_request import LlmRequest
+from google.adk.plugins.multimodal_tool_results_plugin import MultimodalToolResultsPlugin
+from google.adk.plugins.multimodal_tool_results_plugin import PARTS_RETURNED_BY_TOOLS_ID
+from google.adk.tools.base_tool import BaseTool
+from google.adk.tools.tool_context import ToolContext
+from google.genai import types
+import pytest
+
+from .. import testing_utils
+
+
+@pytest.fixture
+def plugin() -> MultimodalToolResultsPlugin:
+  """Create a default plugin instance for testing."""
+  return MultimodalToolResultsPlugin()
+
+
+@pytest.fixture
+def mock_tool() -> MockTool:
+  """Create a mock tool for testing."""
+  return Mock(spec=BaseTool)
+
+
+@pytest.fixture
+async def tool_context() -> ToolContext:
+  """Create a mock tool context."""
+  return ToolContext(
+      invocation_context=await testing_utils.create_invocation_context(
+          agent=Mock(spec=BaseAgent)
+      )
+  )
+
+
+@pytest.mark.asyncio
+async def test_tool_returning_parts_are_added_to_llm_request(
+    plugin: MultimodalToolResultsPlugin,
+    mock_tool: MockTool,
+    tool_context: ToolContext,
+):
+  """Test that parts returned by a tool are present in the llm_request later."""
+  parts = [types.Part(text="part1"), types.Part(text="part2")]
+
+  result = await plugin.after_tool_callback(
+      tool=mock_tool,
+      tool_args={},
+      tool_context=tool_context,
+      result=parts,
+  )
+
+  assert result == None
+  assert PARTS_RETURNED_BY_TOOLS_ID in tool_context.state
+  assert tool_context.state[PARTS_RETURNED_BY_TOOLS_ID] == parts
+
+  callback_context = Mock(spec=CallbackContext)
+  callback_context.state = tool_context.state
+  llm_request = LlmRequest(contents=[types.Content(parts=[])])
+
+  await plugin.before_model_callback(
+      callback_context=callback_context, llm_request=llm_request
+  )
+
+  assert llm_request.contents[-1].parts == parts
+
+
+@pytest.mark.asyncio
+async def test_tool_returning_non_list_of_parts_is_unchanged(
+    plugin: MultimodalToolResultsPlugin,
+    mock_tool: MockTool,
+    tool_context: ToolContext,
+):
+  """Test where tool returning non list of parts, has this result unchanged."""
+  original_result = {"some": "data"}
+
+  result = await plugin.after_tool_callback(
+      tool=mock_tool,
+      tool_args={},
+      tool_context=tool_context,
+      result=original_result,
+  )
+
+  assert result == original_result
+  assert PARTS_RETURNED_BY_TOOLS_ID not in tool_context.state
+
+  callback_context = Mock(spec=CallbackContext)
+  callback_context.state = tool_context.state
+  llm_request = LlmRequest(
+      contents=[types.Content(parts=[types.Part(text="original")])]
+  )
+  original_parts = list(llm_request.contents[-1].parts)
+
+  await plugin.before_model_callback(
+      callback_context=callback_context, llm_request=llm_request
+  )
+
+  assert llm_request.contents[-1].parts == original_parts
+
+
+@pytest.mark.asyncio
+async def test_multiple_tools_returning_parts_are_accumulated(
+    plugin: ToolReturningGenAiPartsPlugin,
+    mock_tool: MockTool,
+    tool_context: ToolContext,
+):
+  """Test that parts from multiple tool calls are accumulated."""
+  parts1 = [types.Part(text="part1")]
+  parts2 = [types.Part(text="part2")]
+
+  await plugin.after_tool_callback(
+      tool=mock_tool,
+      tool_args={},
+      tool_context=tool_context,
+      result=parts1,
+  )
+
+  await plugin.after_tool_callback(
+      tool=mock_tool,
+      tool_args={},
+      tool_context=tool_context,
+      result=parts2,
+  )
+
+  assert PARTS_RETURNED_BY_TOOLS_ID in tool_context.state
+  assert tool_context.state[PARTS_RETURNED_BY_TOOLS_ID] == parts1 + parts2
+
+  callback_context = Mock(spec=CallbackContext)
+  callback_context.state = tool_context.state
+  llm_request = LlmRequest(contents=[types.Content(parts=[])])
+
+  await plugin.before_model_callback(
+      callback_context=callback_context, llm_request=llm_request
+  )
+
+  assert llm_request.contents[-1].parts == parts1 + parts2