truncate method
Returns a copy of this truncated to the TemporalUnit.
final date = ZonedDateTime('Asia/Singapore', 2023, 4, 15);
date.truncate(to: DateUnit.months); // 2023-04-01T00:00+08:00[Asia/Singapore]
Implementation
@useResult ZonedDateTime truncate({required TemporalUnit to}) => ZonedDateTime._convert(timezone, _native.truncate(to: to));