refactor: remove custom test overrides and use monkeypatch

Author: chalmerlowe

packages/google-api-core/google/api_core/feature_gating_helpers.py

@@ -24,11 +24,6 @@
 _TRUTHY_VALUES = ("y", "yes", "t", "true", "on", "1")
 _FALSY_VALUES = ("n", "no", "f", "false", "off", "0")
 
-# Test-only overrides for environment variables.
-# This is intended ONLY for unit/integration testing to prevent mutating
-# os.environ.
-_TEST_ENV_OVERRIDES: Dict[str, bool] = {}
-
 
 def _strtobool(val: str) -> Optional[bool]:
     """Convert a string representation of truth to a boolean."""
@@ -42,28 +37,8 @@ def _strtobool(val: str) -> Optional[bool]:
     raise ValueError(f"Invalid truth value: {val!r}")
 
 
-def set_test_env_override(name: str, value: Optional[bool]) -> None:
-    """Sets a test-only override for a specific environment variable.
-
-    This is intended ONLY for unit/integration testing to prevent mutating
-    os.environ.
-    """
-    if value is None:
-        _TEST_ENV_OVERRIDES.pop(name, None)
-    else:
-        _TEST_ENV_OVERRIDES[name] = value
-
-
-def clear_test_env_overrides() -> None:
-    """Clears all test-only overrides."""
-    _TEST_ENV_OVERRIDES.clear()
-
-
 def _get_env_bool(name: str) -> Optional[bool]:
     """Retrieve the boolean value of an environment variable."""
-    if name in _TEST_ENV_OVERRIDES:
-        return _TEST_ENV_OVERRIDES[name]
-
     val = os.getenv(name)
     if val is None:
         return None
@@ -108,7 +83,7 @@ def resolve_feature_flags(
     Args:
         env_var: The name of the environment variable controlling this feature.
         provider_key: The key in client_options/attributes for the programmatic provider.
-        client_options: A dictionary or object containing client configuration.
+        client_options: Optional. A dictionary or object containing client configuration.
 
     Returns:
         bool: True if the feature is resolved to enabled, False otherwise.

packages/google-api-core/tests/unit/test_feature_gating_helpers.py

@@ -17,17 +17,9 @@
 from google.api_core.feature_gating_helpers import (
     _get_env_bool,
     _strtobool,
-    clear_test_env_overrides,
-    set_test_env_override,
 )
 
 
-@pytest.fixture(autouse=True)
-def clean_overrides():
-    yield
-    clear_test_env_overrides()
-
-
 @pytest.mark.parametrize(
     "value,expected",
     [
@@ -74,30 +66,12 @@ def test_get_env_bool(monkeypatch):
     assert _get_env_bool("TEST_VAR") is None
 
 
-def test_set_test_env_override_clear_specific():
-    """Verify that setting an override to None clears that specific override.
-
-    This is important to ensure tests can reset individual environment overrides
-    without affecting other overrides that might be set for other tests running
-    concurrently or subsequently.
-    """
-    set_test_env_override("TEST_A", True)
-    set_test_env_override("TEST_B", True)
-    assert _get_env_bool("TEST_A") is True
-    assert _get_env_bool("TEST_B") is True
 
-    # Clear only TEST_A
-    set_test_env_override("TEST_A", None)
 
-    # Verify TEST_A is cleared but TEST_B remains
-    assert _get_env_bool("TEST_A") is None
-    assert _get_env_bool("TEST_B") is True
-
-
-def test_resolve_feature_flags_ga_enabled_via_env():
+def test_resolve_feature_flags_ga_enabled_via_env(monkeypatch):
     """Verify that a GA feature is enabled if its environment variable is True."""
     # Setup: We pass a GA environment variable set to True
-    set_test_env_override("GOOGLE_SDK_PYTHON_TRACING_ENABLED", True)
+    monkeypatch.setenv("GOOGLE_SDK_PYTHON_TRACING_ENABLED", "true")
 
     # Action
     result = feature_gating_helpers.resolve_feature_flags(
@@ -110,13 +84,14 @@ def test_resolve_feature_flags_ga_enabled_via_env():
     assert result is True
 
 
-@pytest.mark.parametrize("exp_env_state", [None, False], ids=["missing", "disabled"])
-def test_resolve_feature_flags_exp_blocked_with_provider_fails_fast(exp_env_state):
+@pytest.mark.parametrize("exp_env_state", [None, "false"], ids=["missing", "disabled"])
+def test_resolve_feature_flags_exp_blocked_with_provider_fails_fast(monkeypatch, exp_env_state):
     """Verify that passing a provider to an experimental feature raises ValueError if the experimental environment variable is disabled or missing."""
     # Setup: Experimental env var is set to exp_env_state (None means not set)
-    set_test_env_override(
-        "GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", exp_env_state
-    )
+    if exp_env_state is not None:
+        monkeypatch.setenv("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", exp_env_state)
+    else:
+        monkeypatch.delenv("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", raising=False)
     client_options = {"tracer_provider": object()}
 
     # Action & Assertion
@@ -128,9 +103,9 @@ def test_resolve_feature_flags_exp_blocked_with_provider_fails_fast(exp_env_stat
         )
 
 
-def test_resolve_feature_flags_exp_enabled_with_provider():
+def test_resolve_feature_flags_exp_enabled_with_provider(monkeypatch):
     """Verify that experimental feature is enabled if the experimental environment variable is enabled and a provider is provided."""
-    set_test_env_override("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", True)
+    monkeypatch.setenv("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", "true")
     client_options = {"tracer_provider": object()}
 
     result = feature_gating_helpers.resolve_feature_flags(
@@ -141,9 +116,9 @@ def test_resolve_feature_flags_exp_enabled_with_provider():
     assert result is True
 
 
-def test_resolve_feature_flags_exp_enabled_without_provider():
+def test_resolve_feature_flags_exp_enabled_without_provider(monkeypatch):
     """Verify that experimental feature is enabled if the experimental environment variable is enabled and NO provider is provided."""
-    set_test_env_override("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", True)
+    monkeypatch.setenv("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", "true")
 
     result = feature_gating_helpers.resolve_feature_flags(
         env_var="GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED",
@@ -153,9 +128,9 @@ def test_resolve_feature_flags_exp_enabled_without_provider():
     assert result is True
 
 
-def test_resolve_feature_flags_exp_disabled_without_provider():
+def test_resolve_feature_flags_exp_disabled_without_provider(monkeypatch):
     """Verify that experimental feature is disabled if the experimental environment variable is disabled and NO provider is provided."""
-    set_test_env_override("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", False)
+    monkeypatch.setenv("GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED", "false")
 
     result = feature_gating_helpers.resolve_feature_flags(
         env_var="GOOGLE_SDK_EXPERIMENTAL_PYTHON_TRACING_ENABLED",
@@ -165,10 +140,10 @@ def test_resolve_feature_flags_exp_disabled_without_provider():
     assert result is False
 
 
-def test_resolve_feature_flags_ga_enabled_via_provider():
+def test_resolve_feature_flags_ga_enabled_via_provider(monkeypatch):
     """Verify that a GA feature is enabled if a provider is provided, ignoring the environment variable."""
     # Env var is False, but provider is present
-    set_test_env_override("GOOGLE_SDK_PYTHON_TRACING_ENABLED", False)
+    monkeypatch.setenv("GOOGLE_SDK_PYTHON_TRACING_ENABLED", "false")
     client_options = {"tracer_provider": object()}
 
     result = feature_gating_helpers.resolve_feature_flags(
@@ -180,11 +155,14 @@ def test_resolve_feature_flags_ga_enabled_via_provider():
 
 
 @pytest.mark.parametrize(
-    "env_val", [None, False], ids=["env_not_set", "env_explicit_false"]
+    "env_val", [None, "false"], ids=["env_not_set", "env_explicit_false"]
 )
-def test_resolve_feature_flags_ga_fallback_to_false(env_val):
+def test_resolve_feature_flags_ga_fallback_to_false(monkeypatch, env_val):
     """Verify that a GA feature is disabled if neither a provider is provided nor the environment variable is enabled."""
-    set_test_env_override("GOOGLE_SDK_PYTHON_TRACING_ENABLED", env_val)
+    if env_val is not None:
+        monkeypatch.setenv("GOOGLE_SDK_PYTHON_TRACING_ENABLED", env_val)
+    else:
+        monkeypatch.delenv("GOOGLE_SDK_PYTHON_TRACING_ENABLED", raising=False)
     result = feature_gating_helpers.resolve_feature_flags(
         env_var="GOOGLE_SDK_PYTHON_TRACING_ENABLED",
         provider_key="tracer_provider",