php interval and timezone

Question

I would like to get the date time interval between two dates in a time zone that uses daylight savings time.

The following snipet shows the problem.

$timezone = new DateTimeZone('UTC');
$from_date_obj = DateTime::createFromFormat('Y-m-d H:i:s', '2014-10-31 23:59:59',$timezone);
$to_date_obj = DateTime::createFromFormat('Y-m-d H:i:s', '2014-11-20 23:47:02',$timezone);
$interval = $from_date_obj->diff($to_date_obj, TRUE);
print_r($interval);

For UTC timezone this shows:

DateInterval Object
(
[y] => 0
[m] => 0
[d] => 19
[h] => 23
[i] => 47
[s] => 3
[weekday] => 0
[weekday_behavior] => 0
[first_last_day_of] => 0
[invert] => 0
[days] => 19
[special_type] => 0
[special_amount] => 0
[have_weekday_relative] => 0
[have_special_relative] => 0
)

Now this one:

$timezone = new DateTimeZone('America/Los_Angeles');
$from_date_obj = DateTime::createFromFormat('Y-m-d H:i:s', '2014-10-31 23:59:59',$timezone);
$to_date_obj = DateTime::createFromFormat('Y-m-d H:i:s', '2014-11-20 23:47:02',$timezone);
$interval = $from_date_obj->diff($to_date_obj, TRUE);
print_r($interval);

shows:

DateInterval Object 
(
[y] => 0
[m] => 0
[d] => 20
[h] => -1
[i] => 47
[s] => 3
[weekday] => 0
[weekday_behavior] => 0
[first_last_day_of] => 0
[invert] => 0
[days] => 19
[special_type] => 0
[special_amount] => 0
[have_weekday_relative] => 0
[have_special_relative] => 0
)

the one in UTC shows 19 days/23 hours/47 minutes and 3 seconds. The one for PT shows 20 days/-1 hours/47 minutes and 3 seconds. I think the right answer for PT should be 20 days/0 hours/47 minutes and 3 seconds.

Is there any way to do a diff in the pacific time zone and not end up with the negative hour? Is the -1 hours indication the desired result and what does it mean exactly?

update: I found out that indeed PHP doesn't seem to handle the diff with respect to DST which is discussed here:

PHP's DateTime::Diff gets it wrong?

As far as the results I was getting it appears to be a PHP bug as indicated in the above link.

Gal Gal · Accepted Answer · 2015-02-21T11:25:59

What php version are you using ? Im getting this result for 2nd code block -

DateInterval Object ( 
[y] => 0 
[m] => 0 
[d] => 19 
[h] => 23 
[i] => 47 
[s] => 3 
[weekday] => 0 
[weekday_behavior] => 0 
[first_last_day_of] => 0 
[invert] => 0 
[days] => 19 
[special_type] => 0 
[special_amount] => 0 
[have_weekday_relative] => 0 
[have_special_relative] => 0 
)

both of the codes should display the same result as your comparing the same date with just different timezone each time

php interval and timezone

2 Answers