Use NestedSet to also remove structs owned by no-one

Author: apelisse

merge/update.go

@@ -226,7 +226,7 @@ func (s *Updater) prune(merged *typed.TypedValue, managers fieldpath.ManagedFiel
 		return nil, fmt.Errorf("failed to convert merged object to last applied version: %v", err)
 	}
 
-	pruned := convertedMerged.RemoveItems(lastSet.Set())
+	pruned := convertedMerged.RemoveItems(lastSet.Set().NestedSet())
 	pruned, err = s.addBackOwnedItems(convertedMerged, pruned, managers, applyingManager)
 	if err != nil {
 		return nil, fmt.Errorf("failed add back owned items: %v", err)
@@ -247,7 +247,11 @@ func (s *Updater) addBackOwnedItems(merged, pruned *typed.TypedValue, managedFie
 		if _, ok := managedAtVersion[managerSet.APIVersion()]; !ok {
 			managedAtVersion[managerSet.APIVersion()] = fieldpath.NewSet()
 		}
-		managedAtVersion[managerSet.APIVersion()] = managedAtVersion[managerSet.APIVersion()].Union(managerSet.Set())
+		managed := managerSet.Set()
+		if managerSet.Applied() {
+			managed = managed.NestedSet()
+		}
+		managedAtVersion[managerSet.APIVersion()] = managedAtVersion[managerSet.APIVersion()].Union(managed)
 	}
 	for version, managed := range managedAtVersion {
 		merged, err = s.Converter.Convert(merged, version)
@@ -272,7 +276,7 @@ func (s *Updater) addBackOwnedItems(merged, pruned *typed.TypedValue, managedFie
 		if err != nil {
 			return nil, fmt.Errorf("failed to create field set from pruned object at version %v: %v", version, err)
 		}
-		pruned = merged.RemoveItems(mergedSet.Difference(prunedSet.Union(managed)))
+		pruned = merged.RemoveItems(mergedSet.NestedSet().Difference(prunedSet.NestedSet().Union(managed)))
 	}
 	return pruned, nil
 }
@@ -296,7 +300,7 @@ func (s *Updater) addBackDanglingItems(merged, pruned *typed.TypedValue, lastSet
 	if err != nil {
 		return nil, fmt.Errorf("failed to create field set from merged object in last applied version: %v", err)
 	}
-	return merged.RemoveItems(mergedSet.Difference(prunedSet).Intersection(lastSet.Set())), nil
+	return merged.RemoveItems(mergedSet.NestedSet().Difference(prunedSet.NestedSet()).Intersection(lastSet.Set().NestedSet())), nil
 }
 
 // reconcileManagedFieldsWithSchemaChanges reconciles the managed fields with any changes to the

typed/tofieldset.go

@@ -137,7 +137,9 @@ func (v *toFieldSetWalker) visitMapItems(t *schema.Map, m value.Map) (errs Valid
 		v2 := v.prepareDescent(pe, tr)
 		v2.value = val
 		errs = append(errs, v2.toFieldSet()...)
-		if _, ok := t.FindField(key); !ok {
+		if val.IsNull() || (val.IsMap() && val.AsMap().Length() == 0) {
+			v2.set.Insert(v2.path)
+		} else if _, ok := t.FindField(key); !ok {
 			v2.set.Insert(v2.path)
 		}
 		v.finishDescent(v2)