Using runZoned to catch print() logs

main.dart

import 'dart:async';

/// This service logs via [print]. Ugh.
void runMisbehavingService() async {
  print('Starting service...');
  await Future.delayed(const Duration(milliseconds: 100));
  print('... started.');
}


void main() async {
  var logMessages = <String>[];
  
  // We're running the service in its own Zone.
  runZoned(
    () => runMisbehavingService(),
    // Here, we can give options to the new Zone.
    zoneSpecification: ZoneSpecification(
      // For example, we can overload the `print` statement.
      print: (self, parent, zone, line) => logMessages.add(line),
    ),
  );
  
  print('Service generated ${logMessages.length} log(s) so far: $logMessages');
  await Future.delayed(const Duration(seconds: 1));
  print('Service generated ${logMessages.length} log(s) so far: $logMessages');
  // Note how the Zone keeps working even with asynchronous code.
}