Merge pull request kubernetes#130878 from yongruilin/compatibility-version-featuregate

feat: Add alpha feature verification to feature gates

Author: k8s-ci-robot

test/compatibility_lifecycle/cmd/feature_gates.go

@@ -134,6 +134,10 @@ func verifyOrUpdateFeatureList(rootPath, featureListFile string, currentVersion
 	}
 	featureList = append(featureList, features...)
 
+	if err := verifyAlphaFeatures(featureList); err != nil {
+		return err
+	}
+
 	sort.Slice(featureList, func(i, j int) bool {
 		return strings.ToLower(featureList[i].Name) < strings.ToLower(featureList[j].Name)
 	})
@@ -175,7 +179,7 @@ func verifyOrUpdateFeatureList(rootPath, featureListFile string, currentVersion
 }
 
 func dedupeFeatureList(featureList []featureInfo) ([]featureInfo, error) {
-	if featureList == nil || len(featureList) < 1 {
+	if len(featureList) < 1 {
 		return featureList, nil
 	}
 	last := featureList[0]
@@ -262,6 +266,17 @@ func verifyFeatureRemoval(featureList []featureInfo, baseFeatureList []featureIn
 	return nil
 }
 
+func verifyAlphaFeatures(featureList []featureInfo) error {
+	for _, f := range featureList {
+		for _, spec := range f.VersionedSpecs {
+			if spec.PreRelease == "Alpha" && spec.Default {
+				return fmt.Errorf("alpha feature %s cannot be enabled by default", f.Name)
+			}
+		}
+	}
+	return nil
+}
+
 func searchPathForFeatures(path string) ([]featureInfo, error) {
 	allFeatures := []featureInfo{}
 	// Create a FileSet to work with

test/compatibility_lifecycle/cmd/feature_gates_test.go

@@ -894,3 +894,53 @@ func TestVerifyFeatureRemoval(t *testing.T) {
 		})
 	}
 }
+
+func TestVerifyAlphaFeatures(t *testing.T) {
+	tests := []struct {
+		name           string
+		featureList    []featureInfo
+		expectErr      bool
+		expectedErrMsg string
+	}{
+		{
+			name: "no alpha features",
+			featureList: []featureInfo{
+				{Name: "FeatureB", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "Beta"}}},
+				{Name: "FeatureC", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "GA", LockToDefault: true}}},
+			},
+		},
+		{
+			name: "alpha feature disabled",
+			featureList: []featureInfo{
+				{Name: "FeatureA", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "Alpha", Default: false}}},
+				{Name: "FeatureB", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "Beta"}}},
+			},
+		},
+		{
+			name: "alpha feature enabled",
+			featureList: []featureInfo{
+				{Name: "FeatureA", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "Alpha", Default: true}}},
+				{Name: "FeatureB", VersionedSpecs: []featureSpec{{Version: "1.0", PreRelease: "Beta"}}},
+			},
+			expectErr:      true,
+			expectedErrMsg: "alpha feature FeatureA cannot be enabled by default",
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			err := verifyAlphaFeatures(tc.featureList)
+			if tc.expectErr {
+				if err == nil {
+					t.Fatalf("expected error, got nil")
+				}
+				if !strings.Contains(err.Error(), tc.expectedErrMsg) {
+					t.Fatalf("expected error message to contain %q, got %q", tc.expectedErrMsg, err.Error())
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+		})
+	}
+}