private static List<PsiReference> returnTypes(PsiElement element,
                                                StructuredDocString docString,
                                                int offset) {
    List<PsiReference> result = new ArrayList<>();

    final Substring rtype = docString.getReturnTypeSubstring();
    if (rtype != null) {
      result.addAll(parseTypeReferences(element, rtype, offset));
    }
    return result;
  }
private static List<PsiReference> returnTypes(PsiElement element,
                                                StructuredDocString docString,
                                                int offset)