isBase64 property won't work on release build

[brunodmn]

I am trying to use isBase64 to check whether base64 string is valid before write and open a pdf file, but it works only on debug mode. When I compile release and try to use it, simply does nothing.

sample code:

import 'package:path_provider/path_provider.dart';
import 'dart:convert';
import 'package:open_file/open_file.dart';
import 'package:path_provider/path_provider.dart';

 Future<void> downloadPDF (String base64) async 
{
if(!isBase64(base64)
{
return ;
}

var bytes = base64Decode(base64);
   try {
      var output = await getTemporaryDirectory();
      var file = File("${output.path}/myFile.pdf");
      await file.writeAsBytes(bytes.buffer.asUint8List());
      await OpenFile.open("${output.path}/boleto.pdf");
    } catch (e) {
      print("$e");
    }
 }

Workaround is not to use the property and wrap code inside try block