[FSSDK-12368] Add tests for local holdouts in feature experiments

- Add TestGetDecisionWithLocalHoldout: user bucketed into holdout
- Add TestGetDecisionWithLocalHoldoutNotBucketed: 0% traffic falls through
- Add TestGetDecisionWithLocalHoldoutNotRunning: draft holdout skipped
- Improves coverage for evaluateHoldout method (77 uncovered lines)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Mat001

pkg/decision/feature_experiment_service_test.go

@@ -295,6 +295,146 @@ func (s *FeatureExperimentServiceTestSuite) TestGetDecisionWithCmabError() {
 	s.mockExperimentService.AssertExpectations(s.T())
 }
 
+func (s *FeatureExperimentServiceTestSuite) TestGetDecisionWithLocalHoldout() {
+	testUserContext := entities.UserContext{
+		ID: "test_user_1",
+	}
+
+	// Create holdout variation
+	holdoutVariation := entities.Variation{
+		ID:  "holdout_var_1",
+		Key: "holdout_off",
+	}
+
+	// Create local holdout targeting the first experiment
+	localHoldout := entities.Holdout{
+		ID:     "local_holdout_1",
+		Key:    "local_holdout_key",
+		Status: entities.HoldoutStatusRunning,
+		Variations: map[string]entities.Variation{
+			"holdout_var_1": holdoutVariation,
+		},
+		TrafficAllocation: []entities.Range{
+			{EntityID: "holdout_var_1", EndOfRange: 10000},
+		},
+		IncludedRules: []string{testExp1113.ID}, // Target first experiment
+	}
+
+	// Mock GetHoldoutsForRule to return our local holdout
+	s.mockConfig.On("GetHoldoutsForRule", testExp1113.ID).Return([]entities.Holdout{localHoldout})
+	s.mockConfig.On("GetAudienceMap").Return(map[string]entities.Audience{})
+
+	featureExperimentService := &FeatureExperimentService{
+		compositeExperimentService: s.mockExperimentService,
+		logger:                     logging.GetLogger("sdkKey", "FeatureExperimentService"),
+	}
+
+	decision, _, err := featureExperimentService.GetDecision(s.testFeatureDecisionContext, testUserContext, s.options)
+	s.NoError(err)
+	s.Equal(Holdout, decision.Source)
+	s.Equal(&holdoutVariation, decision.Variation)
+	s.mockConfig.AssertExpectations(s.T())
+}
+
+func (s *FeatureExperimentServiceTestSuite) TestGetDecisionWithLocalHoldoutNotBucketed() {
+	testUserContext := entities.UserContext{
+		ID: "test_user_1",
+	}
+
+	// Create holdout variation
+	holdoutVariation := entities.Variation{
+		ID:  "holdout_var_1",
+		Key: "holdout_off",
+	}
+
+	// Create local holdout with 0% traffic
+	localHoldout := entities.Holdout{
+		ID:     "local_holdout_1",
+		Key:    "local_holdout_key",
+		Status: entities.HoldoutStatusRunning,
+		Variations: map[string]entities.Variation{
+			"holdout_var_1": holdoutVariation,
+		},
+		TrafficAllocation: []entities.Range{
+			{EntityID: "holdout_var_1", EndOfRange: 0}, // 0% traffic
+		},
+		IncludedRules: []string{testExp1113.ID},
+	}
+
+	s.mockConfig.On("GetHoldoutsForRule", testExp1113.ID).Return([]entities.Holdout{localHoldout})
+	s.mockConfig.On("GetAudienceMap").Return(map[string]entities.Audience{})
+
+	// User should fall through to normal experiment evaluation
+	expectedVariation := testExp1113.Variations["2223"]
+	returnExperimentDecision := ExperimentDecision{
+		Variation: &expectedVariation,
+	}
+	testExperimentDecisionContext := ExperimentDecisionContext{
+		Experiment:    &testExp1113,
+		ProjectConfig: s.mockConfig,
+	}
+	s.mockExperimentService.On("GetDecision", testExperimentDecisionContext, testUserContext, s.options).Return(returnExperimentDecision, s.reasons, nil)
+
+	featureExperimentService := &FeatureExperimentService{
+		compositeExperimentService: s.mockExperimentService,
+		logger:                     logging.GetLogger("sdkKey", "FeatureExperimentService"),
+	}
+
+	decision, _, err := featureExperimentService.GetDecision(s.testFeatureDecisionContext, testUserContext, s.options)
+	s.NoError(err)
+	s.Equal(FeatureTest, decision.Source) // Should be from feature test, not holdout
+	s.mockExperimentService.AssertExpectations(s.T())
+	s.mockConfig.AssertExpectations(s.T())
+}
+
+func (s *FeatureExperimentServiceTestSuite) TestGetDecisionWithLocalHoldoutNotRunning() {
+	testUserContext := entities.UserContext{
+		ID: "test_user_1",
+	}
+
+	// Create holdout variation
+	holdoutVariation := entities.Variation{
+		ID:  "holdout_var_1",
+		Key: "holdout_off",
+	}
+
+	// Create local holdout that's not running
+	localHoldout := entities.Holdout{
+		ID:     "local_holdout_1",
+		Key:    "local_holdout_key",
+		Status: "Draft", // Not running
+		Variations: map[string]entities.Variation{
+			"holdout_var_1": holdoutVariation,
+		},
+		TrafficAllocation: []entities.Range{{EntityID: "holdout_var_1", EndOfRange: 10000}},
+		IncludedRules:     []string{testExp1113.ID},
+	}
+
+	s.mockConfig.On("GetHoldoutsForRule", testExp1113.ID).Return([]entities.Holdout{localHoldout})
+
+	// User should fall through to normal experiment evaluation
+	expectedVariation := testExp1113.Variations["2223"]
+	returnExperimentDecision := ExperimentDecision{
+		Variation: &expectedVariation,
+	}
+	testExperimentDecisionContext := ExperimentDecisionContext{
+		Experiment:    &testExp1113,
+		ProjectConfig: s.mockConfig,
+	}
+	s.mockExperimentService.On("GetDecision", testExperimentDecisionContext, testUserContext, s.options).Return(returnExperimentDecision, s.reasons, nil)
+
+	featureExperimentService := &FeatureExperimentService{
+		compositeExperimentService: s.mockExperimentService,
+		logger:                     logging.GetLogger("sdkKey", "FeatureExperimentService"),
+	}
+
+	decision, _, err := featureExperimentService.GetDecision(s.testFeatureDecisionContext, testUserContext, s.options)
+	s.NoError(err)
+	s.Equal(FeatureTest, decision.Source)
+	s.mockExperimentService.AssertExpectations(s.T())
+	s.mockConfig.AssertExpectations(s.T())
+}
+
 func TestFeatureExperimentServiceTestSuite(t *testing.T) {
 	suite.Run(t, new(FeatureExperimentServiceTestSuite))
 }