chore: import upstream snapshot with attribution

tests/unittests/test_optional_dependencies.py

@@ -0,0 +1,308 @@
+# 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.
+
+"""Tests for optional dependencies and lazy loading.
+
+Includes both fast hermetic unit tests (run by default) and high-fidelity
+integration tests using a clean venv (skipped by default, run via env var).
+"""
+
+from __future__ import annotations
+
+import importlib.util
+import os
+from pathlib import Path
+import subprocess
+import sys
+from unittest import mock
+
+import pytest
+
+_REPO_ROOT = Path(__file__).resolve().parents[2]
+
+# Check if we should run integration tests that require network/install
+RUN_INTEGRATION = os.environ.get("ADK_TEST_NETWORK") == "1"
+
+
+@pytest.fixture(scope="session")
+def clean_core_venv(tmp_path_factory):
+  """Creates a clean venv with only core ADK installed (requires network)."""
+  if not RUN_INTEGRATION:
+    pytest.skip("Integration tests requiring network are disabled by default.")
+
+  venv_path = tmp_path_factory.mktemp("adk_core_venv")
+  python_exe = venv_path / "bin" / "python"
+
+  # Create venv using uv for speed
+  subprocess.run(
+      ["uv", "venv", str(venv_path), "--python", "3.11"],
+      check=True,
+      capture_output=True,
+  )
+
+  # Install core ADK from local repo (uses current pyproject.toml)
+  subprocess.run(
+      ["uv", "pip", "install", "--python", str(python_exe), str(_REPO_ROOT)],
+      check=True,
+      capture_output=True,
+  )
+
+  return python_exe
+
+
+# =============================================================================
+# Approach 1: Hermetic Unit Tests (Fast, No Network, Safe for CI/TAP)
+# =============================================================================
+
+
+def test_pydantic_version():
+  """Print the installed Pydantic version."""
+  import pydantic
+
+  print(f"Pydantic version: {pydantic.__version__}")
+  assert True
+
+
+def test_no_eager_imports():
+  """Verify that importing google.adk does not eagerly load heavy optional deps.
+
+  Runs in the current environment but in a fresh subprocess, ensuring it
+  only checks the import side-effects without modifying the environment.
+  """
+  code = """
+import sys
+import google.adk
+heavy_modules = ['google.cloud.aiplatform', 'sqlalchemy', 'a2a']
+loaded = [mod for mod in heavy_modules if mod in sys.modules]
+print(','.join(loaded))
+"""
+  result = subprocess.run(
+      [sys.executable, "-c", code], capture_output=True, text=True, check=True
+  )
+  loaded_modules = result.stdout.strip()
+  assert loaded_modules == "", f"Heavy modules loaded eagerly: {loaded_modules}"
+
+
+def test_a2a_remote_agent_config_raises_importerror():
+  """Verify that accessing A2aRemoteAgentConfig without extra raises ImportError using mocks."""
+  with mock.patch.dict("sys.modules", {"a2a": None}):
+    for mod in list(sys.modules):
+      if mod.startswith("a2a.") or mod.startswith("google.adk.a2a."):
+        sys.modules.pop(mod, None)
+    with pytest.raises(ImportError) as exc_info:
+      from google.adk.a2a.agent import A2aRemoteAgentConfig
+    assert "a2a-sdk" in str(exc_info.value)
+
+
+def test_vertex_ai_memory_bank_service_fails_on_creation():
+  """Verify that creating VertexAiMemoryBankService without extra fails using mocks."""
+  try:
+    from google.adk.memory import VertexAiMemoryBankService
+  except KeyError as e:
+    if "pydantic.root_model" in str(e):
+      pytest.skip(
+          "Skipping mock test due to Pydantic/MCP environment conflict"
+          " (KeyError: 'pydantic.root_model')."
+      )
+    raise
+
+  with mock.patch.dict("sys.modules", {"vertexai": None}):
+    sys.modules.pop("google.adk.memory.vertex_ai_memory_bank_service", None)
+    from google.adk.memory import VertexAiMemoryBankService
+
+    with pytest.raises(ImportError) as exc_info:
+      VertexAiMemoryBankService(agent_engine_id="123")
+    assert "google-cloud-aiplatform" in str(exc_info.value)
+
+
+def test_database_session_service_fails_on_creation():
+  """Verify that creating DatabaseSessionService without extra fails using mocks."""
+  try:
+    from google.adk.sessions import DatabaseSessionService
+  except KeyError as e:
+    if "pydantic.root_model" in str(e):
+      pytest.skip(
+          "Skipping mock test due to Pydantic/MCP environment conflict"
+          " (KeyError: 'pydantic.root_model')."
+      )
+    raise
+
+  with mock.patch.dict("sys.modules", {"sqlalchemy": None}):
+    sys.modules.pop("google.adk.sessions.database_session_service", None)
+    with pytest.raises(ImportError) as exc_info:
+      from google.adk.sessions import DatabaseSessionService
+
+      DatabaseSessionService(db_url="sqlite+aiosqlite:///:memory:")
+    assert "sqlalchemy" in str(exc_info.value)
+
+
+def test_vertex_ai_session_service_fails_on_creation():
+  """Verify that creating VertexAiSessionService without extra fails using mocks."""
+  try:
+    from google.adk.sessions import VertexAiSessionService
+  except KeyError as e:
+    if "pydantic.root_model" in str(e):
+      pytest.skip(
+          "Skipping mock test due to Pydantic/MCP environment conflict"
+          " (KeyError: 'pydantic.root_model')."
+      )
+    raise
+
+  with mock.patch.dict("sys.modules", {"vertexai": None}):
+    sys.modules.pop("google.adk.sessions.vertex_ai_session_service", None)
+    from google.adk.sessions import VertexAiSessionService
+
+    with pytest.raises(ImportError) as exc_info:
+      VertexAiSessionService(agent_engine_id="123")
+    assert "google-cloud-aiplatform" in str(exc_info.value)
+
+
+def test_vertexai_dependency_shim_raises_clear_importerror():
+  """Verify that the Vertex AI dependency shim points users to the dependency."""
+  module_path = _REPO_ROOT / "dependencies_internal/vertexai.py"
+  if not module_path.is_file():
+    pytest.skip("Vertex AI dependency shim is not present in this build.")
+  with mock.patch.dict("sys.modules", {"google.cloud.aiplatform": None}):
+    spec = importlib.util.spec_from_file_location(
+        "_test_google_adk_dependencies_vertexai", module_path
+    )
+    assert spec is not None
+    assert spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+
+    with pytest.raises(ImportError) as exc_info:
+      spec.loader.exec_module(module)
+
+    message = str(exc_info.value)
+    assert "//third_party/py/google/cloud/aiplatform" in message
+
+
+# =============================================================================
+# Approach 2: High-Fidelity Integration Tests (Clean Venv, Skipped by Default)
+# =============================================================================
+
+
+@pytest.mark.skipif(not RUN_INTEGRATION, reason="Requires ADK_TEST_NETWORK=1")
+def test_critical_imports_subprocess(clean_core_venv):
+  """Verify that all critical import paths in core work in a true core-only environment."""
+  imports = [
+      "import google.adk",
+      "from google.adk import Agent",
+      "from google.adk import Context",
+      "from google.adk import Event",
+      "from google.adk import Runner",
+      "from google.adk import Workflow",
+  ]
+  for imp in imports:
+    result = subprocess.run(
+        [str(clean_core_venv), "-c", imp],
+        capture_output=True,
+        text=True,
+    )
+    assert (
+        result.returncode == 0
+    ), f"Failed to import: {imp}\nStderr: {result.stderr}"
+
+
+@pytest.mark.skipif(not RUN_INTEGRATION, reason="Requires ADK_TEST_NETWORK=1")
+def test_a2a_remote_agent_config_raises_importerror_subprocess(clean_core_venv):
+  """Verify that accessing A2aRemoteAgentConfig without extra raises ImportError in clean environment."""
+  code = """
+try:
+    from google.adk.a2a.agent import A2aRemoteAgentConfig
+    print("SUCCESS")
+except ImportError as e:
+    print(f"CAUGHT_IMPORT_ERROR: {e}")
+"""
+  result = subprocess.run(
+      [str(clean_core_venv), "-c", code],
+      capture_output=True,
+      text=True,
+      check=True,
+  )
+  output = result.stdout.strip()
+  assert "CAUGHT_IMPORT_ERROR" in output
+  assert "a2a-sdk" in output
+
+
+@pytest.mark.skipif(not RUN_INTEGRATION, reason="Requires ADK_TEST_NETWORK=1")
+def test_vertex_ai_memory_bank_service_fails_on_creation_subprocess(
+    clean_core_venv,
+):
+  """Verify that creating VertexAiMemoryBankService without extra fails in clean environment."""
+  code = """
+from google.adk.memory import VertexAiMemoryBankService
+try:
+    service = VertexAiMemoryBankService(agent_engine_id="123")
+    print("SUCCESS")
+except ImportError as e:
+    print(f"CAUGHT_IMPORT_ERROR: {e}")
+"""
+  result = subprocess.run(
+      [str(clean_core_venv), "-c", code],
+      capture_output=True,
+      text=True,
+      check=True,
+  )
+  output = result.stdout.strip()
+  assert "CAUGHT_IMPORT_ERROR" in output
+  assert "google-cloud-aiplatform" in output
+
+
+@pytest.mark.skipif(not RUN_INTEGRATION, reason="Requires ADK_TEST_NETWORK=1")
+def test_database_session_service_fails_on_creation_subprocess(
+    clean_core_venv,
+):
+  """Verify that creating DatabaseSessionService without extra fails in clean environment."""
+  code = """
+try:
+    from google.adk.sessions import DatabaseSessionService
+    service = DatabaseSessionService(db_url="sqlite+aiosqlite:///:memory:")
+    print("SUCCESS")
+except ImportError as e:
+    print(f"CAUGHT_IMPORT_ERROR: {e}")
+"""
+  result = subprocess.run(
+      [str(clean_core_venv), "-c", code],
+      capture_output=True,
+      text=True,
+      check=True,
+  )
+  output = result.stdout.strip()
+  assert "CAUGHT_IMPORT_ERROR" in output
+  assert "sqlalchemy" in output
+
+
+@pytest.mark.skipif(not RUN_INTEGRATION, reason="Requires ADK_TEST_NETWORK=1")
+def test_vertex_ai_session_service_fails_on_creation_subprocess(
+    clean_core_venv,
+):
+  """Verify that creating VertexAiSessionService without extra fails in clean environment."""
+  code = """
+from google.adk.sessions import VertexAiSessionService
+try:
+    service = VertexAiSessionService(agent_engine_id="123")
+    print("SUCCESS")
+except ImportError as e:
+    print(f"CAUGHT_IMPORT_ERROR: {e}")
+"""
+  result = subprocess.run(
+      [str(clean_core_venv), "-c", code],
+      capture_output=True,
+      text=True,
+      check=True,
+  )
+  output = result.stdout.strip()
+  assert "CAUGHT_IMPORT_ERROR" in output
+  assert "google-cloud-aiplatform" in output