}

func populateRefs(schemaOf func(ref string) (*spec.Schema, bool), visited sets.Set[string], schema *spec.Schema) (*spec.Schema, error) {
	result := *schema
	changed := false

	ref, isRef := refOf(schema)
	if isRef {
		if visited.Has(ref) {
			return &spec.Schema{
				// for circular ref, return an empty object as placeholder
				SchemaProps: spec.SchemaProps{Type: []string{"object"}},
			}, nil
		}