Flutter Dart DateTime comparisons for chat messages read/unread

main.dart

void main() {
  var lM = DateTime.parse('2020-01-01T00:00:01');
  var lR = DateTime.parse('2020-01-01T00:00:02');
  print(lM.compareTo(lR)); // Read
  lM = DateTime.parse('2020-01-01T00:00:02');
  lR = DateTime.parse('2020-01-01T00:00:01');
  print(lM.compareTo(lR)); // UnRead
  lM = DateTime.parse('2020-01-01T00:00:01');
  lR = DateTime.parse('2020-01-01T00:00:01');
  print(lM.compareTo(lR)); // UnRead
  
  
  var lr = DateTime.parse('2020-01-01T00:00:01');
  var lm = DateTime.parse('2020-01-01T00:00:02');
  print(lm.compareTo(lr)); // UnRead
  lr = DateTime.parse('2020-01-01T00:00:02');
  lm = DateTime.parse('2020-01-01T00:00:01');
  print(lm.compareTo(lr)); // Read
  lr = DateTime.parse('2020-01-01T00:00:01');
  lm = DateTime.parse('2020-01-01T00:00:01');
  print(lm.compareTo(lr)); // UnRead
}