private static boolean isAppended(PsiReferenceExpression otherRef, PsiExpression expression) {
      expression = PsiUtil.skipParenthesizedExprDown(expression);
      if(expression instanceof PsiPolyadicExpression polyadicExpression) {
        if (polyadicExpression.getOperationTokenType().equals(JavaTokenType.PLUS)) {
          for (PsiExpression operand : polyadicExpression.getOperands()) {
            if (isSameReference(operand, otherRef) || isAppended(otherRef, operand)) return true;
          }
        }
      }
      return false;
    }
private static boolean isAppended(PsiReferenceExpression otherRef, PsiExpression expression)