@Contract("null -> false")
  private static boolean isStringLiteral(@Nullable PsiElement psi) {
    return psi instanceof GrLiteral && TokenSets.STRING_LITERAL_SET.contains(GrLiteralImpl.getLiteralType((GrLiteral)psi)) || psi instanceof GrString;
  }
@Contract("null -> false")
  private static boolean isStringLiteral(@Nullable PsiElement psi)