chore: Raise error when using features decorated by working_in_progress decorator

set environment variable ADK_ALLOW_WIP_FEATURES=true can bypass it.
working_in_progress features are not working. ADK users are not supposed to set this environment variable.

PiperOrigin-RevId: 771333335

tests/unittests/utils/test_feature_decorator.py

@@ -1,3 +1,5 @@
+import os
+import tempfile
 import warnings
 
 from google.adk.utils.feature_decorator import experimental
@@ -11,25 +13,176 @@ class IncompleteFeature:
     return "running"
 
 
+@working_in_progress("function not ready")
+def wip_function():
+  return "executing"
+
+
 @experimental("api may have breaking change in the future.")
 def experimental_fn():
   return "executing"
 
 
-def test_working_in_progress_class_warns():
-  with warnings.catch_warnings(record=True) as w:
-    warnings.simplefilter("always")
+@experimental("class may change")
+class ExperimentalClass:
 
+  def run(self):
+    return "running experimental"
+
+
+def test_working_in_progress_class_raises_error():
+  """Test that WIP class raises RuntimeError by default."""
+  # Ensure environment variable is not set
+  if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+    del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+  try:
     feature = IncompleteFeature()
-
-    assert feature.run() == "running"
-    assert len(w) == 1
-    assert issubclass(w[0].category, UserWarning)
-    assert "[WIP] IncompleteFeature:" in str(w[0].message)
-    assert "don't use yet" in str(w[0].message)
+    assert False, "Expected RuntimeError to be raised"
+  except RuntimeError as e:
+    assert "[WIP] IncompleteFeature:" in str(e)
+    assert "don't use yet" in str(e)
 
 
-def test_experimental_method_warns():
+def test_working_in_progress_function_raises_error():
+  """Test that WIP function raises RuntimeError by default."""
+  # Ensure environment variable is not set
+  if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+    del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+  try:
+    result = wip_function()
+    assert False, "Expected RuntimeError to be raised"
+  except RuntimeError as e:
+    assert "[WIP] wip_function:" in str(e)
+    assert "function not ready" in str(e)
+
+
+def test_working_in_progress_class_bypassed_with_env_var():
+  """Test that WIP class works without warnings when env var is set."""
+  # Set the bypass environment variable
+  os.environ["ADK_ALLOW_WIP_FEATURES"] = "true"
+
+  try:
+    with warnings.catch_warnings(record=True) as w:
+      warnings.simplefilter("always")
+
+      feature = IncompleteFeature()
+      result = feature.run()
+
+      assert result == "running"
+      # Should have no warnings when bypassed
+      assert len(w) == 0
+  finally:
+    # Clean up environment variable
+    if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+      del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+
+def test_working_in_progress_function_bypassed_with_env_var():
+  """Test that WIP function works without warnings when env var is set."""
+  # Set the bypass environment variable
+  os.environ["ADK_ALLOW_WIP_FEATURES"] = "true"
+
+  try:
+    with warnings.catch_warnings(record=True) as w:
+      warnings.simplefilter("always")
+
+      result = wip_function()
+
+      assert result == "executing"
+      # Should have no warnings when bypassed
+      assert len(w) == 0
+  finally:
+    # Clean up environment variable
+    if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+      del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+
+def test_working_in_progress_env_var_case_insensitive():
+  """Test that WIP bypass works with different case values."""
+  test_cases = ["true", "True", "TRUE", "tRuE"]
+
+  for case in test_cases:
+    os.environ["ADK_ALLOW_WIP_FEATURES"] = case
+
+    try:
+      with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+
+        result = wip_function()
+
+        assert result == "executing"
+        assert len(w) == 0
+    finally:
+      if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+        del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+
+def test_working_in_progress_env_var_false_values():
+  """Test that WIP still raises errors with false-like env var values."""
+  false_values = ["false", "False", "FALSE", "0", "", "anything_else"]
+
+  for false_val in false_values:
+    os.environ["ADK_ALLOW_WIP_FEATURES"] = false_val
+
+    try:
+      result = wip_function()
+      assert False, f"Expected RuntimeError with env var '{false_val}'"
+    except RuntimeError as e:
+      assert "[WIP] wip_function:" in str(e)
+    finally:
+      if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+        del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+
+def test_working_in_progress_loads_from_dotenv_file():
+  """Test that WIP decorator can load environment variables from .env file."""
+  # Skip test if dotenv is not available
+  try:
+    from dotenv import load_dotenv
+  except ImportError:
+    import pytest
+
+    pytest.skip("python-dotenv not available")
+
+  # Ensure environment variable is not set in os.environ
+  if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+    del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+  # Create a temporary .env file in current directory
+  dotenv_path = ".env.test"
+
+  try:
+    # Write the env file
+    with open(dotenv_path, "w") as f:
+      f.write("ADK_ALLOW_WIP_FEATURES=true\n")
+
+    # Load the environment variables from the file
+    load_dotenv(dotenv_path)
+
+    with warnings.catch_warnings(record=True) as w:
+      warnings.simplefilter("always")
+
+      # This should work because the .env file contains ADK_ALLOW_WIP_FEATURES=true
+      result = wip_function()
+
+      assert result == "executing"
+      # Should have no warnings when bypassed via .env file
+      assert len(w) == 0
+
+  finally:
+    # Clean up
+    try:
+      os.unlink(dotenv_path)
+    except FileNotFoundError:
+      pass
+    if "ADK_ALLOW_WIP_FEATURES" in os.environ:
+      del os.environ["ADK_ALLOW_WIP_FEATURES"]
+
+
+def test_experimental_function_warns():
+  """Test that experimental function shows warnings (unchanged behavior)."""
   with warnings.catch_warnings(record=True) as w:
     warnings.simplefilter("always")
 
@@ -40,3 +193,18 @@ def test_experimental_method_warns():
     assert issubclass(w[0].category, UserWarning)
     assert "[EXPERIMENTAL] experimental_fn:" in str(w[0].message)
     assert "breaking change in the future" in str(w[0].message)
+
+
+def test_experimental_class_warns():
+  """Test that experimental class shows warnings (unchanged behavior)."""
+  with warnings.catch_warnings(record=True) as w:
+    warnings.simplefilter("always")
+
+    exp_class = ExperimentalClass()
+    result = exp_class.run()
+
+    assert result == "running experimental"
+    assert len(w) == 1
+    assert issubclass(w[0].category, UserWarning)
+    assert "[EXPERIMENTAL] ExperimentalClass:" in str(w[0].message)
+    assert "class may change" in str(w[0].message)