ZonedDateTime::{plus,minus}{Minutes,Hours,Seconds} behaves differently to Java 8

[JanTvrdik]

In Java 8, for example ZonedDateTime.plusMinutes operates on the instant time-line, which means that zonedDateTime.plusMinutes(30) is the same as zonedDateTime.plus(Duration.ofMinutes(30)).

In this library, however,

$zonedDateTime->plusMinutes(30)

is different from

$zonedDateTime->plusDuration(Duration::ofMinutes(30))

If this is intentional behavior change then I think the documenation should be improved (see very good documenation of ZonedDateTime::of()).

If that is unintentional behavior change, that this may be considered a bug report.

[BenMorel]

Hi @JanTvrdik,

I wasn't aware of this difference between brick/date-time and java.time, thanks for bringing it to my attention!

I think it's totally reasonable to expect this to work the same way as it does in Java, so let's consider this a bug report. I'll see if I can find some time to work on this in the coming days, unless you want to open a PR.

However, as this is a BC break, it will require a new version bump (0.8.0), as version 0.7.0 was released just 2 days ago.

[solodkiy]

Just to be clear:

public function plusPeriod(Period $period): ZonedDateTime
{
    return ZonedDateTime::of($this->localDateTime->plusPeriod($period), $this->timeZone);
}

public function plusDuration(Duration $duration): ZonedDateTime
{
    return ZonedDateTime::ofInstant($this->instant->plus($duration), $this->timeZone);
}

Change behavior is happening only when timezone changes between two points of time (like DST).