Copy reference nodes before copying comments and syncing order

kyaml/order/syncorder.go

@@ -13,7 +13,9 @@ import (
 // Field order might be altered due to round-tripping in arbitrary functions.
 // This functionality helps to retain the original order of fields to avoid unnecessary diffs.
 func SyncOrder(from, to *yaml.RNode) error {
-	if err := syncOrder(from, to); err != nil {
+	// from node should not be modified, it should be just used as a reference
+	fromCopy := from.Copy()
+	if err := syncOrder(fromCopy, to); err != nil {
 		return errors.Errorf("failed to sync field order: %q", err.Error())
 	}
 	rearrangeHeadCommentOfSeqNode(to.YNode())

kyaml/order/syncorder_test.go

@@ -5,6 +5,7 @@ package order
 
 import (
 	"bytes"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -413,6 +414,15 @@ status:
 			if !assert.Equal(t, tc.expected, out.String()) {
 				t.FailNow()
 			}
+
+			actualFrom, err := from.String()
+			if !assert.NoError(t, err) {
+				t.FailNow()
+			}
+
+			if !assert.Equal(t, strings.TrimSpace(tc.from), strings.TrimSpace(actualFrom)) {
+				t.FailNow()
+			}
 		})
 	}
 }