DateTime. Bug with winter/summer time

[Aqitaniya]

This tracker is for issues related to:

• Dart core libraries: DateTime

• Dart SDK version: 2.19.6 (stable) (Tue Mar 28 13:41:04 2023 +0000) on "macos_arm64"

Example:

  final DateTime date = DateTime(2023, 03, 27);
  print(date);  // 2023-03-27 00:00:00.000
  print(date.subtract(const Duration(days: 1)));  //2023-03-25 23:00:00.000
  print(date.subtract(const Duration(hours: 24)));  //2023-03-25 23:00:00.000

The same issue with date.add and others

[julemand101]

Works as intended if you read the documentation.

Duplicate of #37449

[lrhn]

Correct. The difference between two local-time DateTime objects is the actual time between the two, and adding Durations to DateTime objects gives the local time after that duration has passed.
Duration doesn't actually understand "days", it just thinks converts them to 24 hours.