Edit report at https://bugs.php.net/bug.php?id=63953&edit=1
ID: 63953
Comment by: chris at modernmedia dot co
Reported by: gianluca dot pinna at allbus dot com
Summary: DateTime::diff produces a wrong DateInterval on DST
change
Status: Open
Type: Bug
Package: Date/time related
Operating System: Linux 64
PHP Version: 5.3.20
Block user comment: N
Private report: N
New Comment:
I can more or less confirm that DateInterval has
Daylight Savings changes backward, at least for my
2014 test cases. In the springtime in the US we
spring forward at 2am on a Sunday morning.
2am and 3am are the same exact time, and share the
same exact timestamp. At 3am, 2 actual hours
have elapsed since midnight.
In the fall we fall backward on a Sunday at 2am.
In this case, at 3am 4 actual hours have elapsed
since midnight.
My code shows that DateTime and DateTimezone
handle DST changes correctly -- its DateInterval
that is having the problem.
Here's my test code:
<?php
/**
Daylight Saving Time (United States) 2014 begins at 2:00 AM on
Sunday, March 9
and ends at 2:00 AM on
Sunday, November 2
*/
$tz = new DateTimeZone( 'America/New_York');
$d1 = new DateTime('2014-03-09 00:00:00', $tz);
echo PHP_EOL;
echo 'Springing forward at 2am on Sunday, March 9, 2014...' . PHP_EOL;
for ($n = 0; $n < 7; $n++){
$d2 = new DateTime(sprintf('2014-03-09 %s:00:00', $n), $tz);
$ts_diff = ($d2->getTimestamp() - $d1->getTimestamp())/(60 * 60);
$int = $d2->diff($d1);
echo 'Comparing ' . $d2->format('g a') . ' to ' . $d1->format('g a') .
PHP_EOL;
echo 'Timestamp diff: ' . $ts_diff . PHP_EOL;
echo 'Interval diff: ' . $int->h . PHP_EOL;
}
echo PHP_EOL;
$d1 = new DateTime('2014-11-02 00:00:00', $tz);
echo 'Falling backward at 2am on Sunday, November 2, 2014...' . PHP_EOL;
for ($n = 0; $n < 7; $n++){
$d2 = new DateTime(sprintf('2014-11-02 %s:00:00', $n), $tz);
$ts_diff = ($d2->getTimestamp() - $d1->getTimestamp())/(60 * 60);
$int = $d2->diff($d1);
echo 'Comparing ' . $d2->format('g a') . ' to ' . $d1->format('g a') .
PHP_EOL;
echo 'Timestamp diff: ' . $ts_diff . PHP_EOL;
echo 'Interval diff: ' . $int->h . PHP_EOL;
}
phpinfo(INFO_GENERAL);
?>
Output
========
Springing forward at 2am on Sunday, March 9, 2014...
Comparing 12 am to 12 am
Timestamp diff: 0
Interval diff: 0
Comparing 1 am to 12 am
Timestamp diff: 1
Interval diff: 1
Comparing 2 am to 12 am
Timestamp diff: 2
Interval diff: 3
Comparing 3 am to 12 am
Timestamp diff: 2
Interval diff: 3
Comparing 4 am to 12 am
Timestamp diff: 3
Interval diff: 4
Comparing 5 am to 12 am
Timestamp diff: 4
Interval diff: 5
Comparing 6 am to 12 am
Timestamp diff: 5
Interval diff: 6
Falling backward at 2am on Sunday, November 2, 2014...
Comparing 12 am to 12 am
Timestamp diff: 0
Interval diff: 0
Comparing 1 am to 12 am
Timestamp diff: 1
Interval diff: 1
Comparing 2 am to 12 am
Timestamp diff: 3
Interval diff: 2
Comparing 3 am to 12 am
Timestamp diff: 4
Interval diff: 3
Comparing 4 am to 12 am
Timestamp diff: 5
Interval diff: 4
Comparing 5 am to 12 am
Timestamp diff: 6
Interval diff: 5
Comparing 6 am to 12 am
Timestamp diff: 7
Interval diff: 6
phpinfo()
PHP Version => 5.4.9
System => Darwin Christophers-MacBook-Air.local 12.4.0 Darwin Kernel Version
12.4.0: Wed May 1 17:57:12 PDT 2013; root:xnu-2050.24.15~1/RELEASE_X86_64
x86_64
Build Date => Dec 11 2012 12:36:33
Previous Comments:
------------------------------------------------------------------------
[2013-02-05 17:42:11] kaido at tradenet dot ee
test script:
$d1 = new DateTime('2012-05-31');
$d2 = new DateTime('2013-03-02');
$diff1 = $d1->diff ($d2);
$diff2 = $d2->diff ($d1);
echo "case 1: ".$diff1->m." months, case 2: ".$diff2->m." months";
expected result:
both $diff1->m and $diff2->m are 9
------------------------------------------------------------------------
[2013-01-09 16:45:28] gianluca dot pinna at allbus dot com
Description:
------------
I have two dates, the second date is after a DST change.
I tried to get a diff between the two dates. Computing the difference between
the
timestamps I get the correct result (33 hours).
Using DateTime->diff() I get 34 hours. Is this expected?
Test script:
---------------
<?php
$originDate = new DateTime('2013-03-30 00:00:00', new
DateTimeZone('Europe/Rome'));
$destinationDate = new DateTime('2013-03-31 10:00:00', new
DateTimeZone('Europe/Rome'));
$diff = $destinationDate->getTimestamp() - $originDate->getTimestamp();
$dateinterval = $originDate->diff($destinationDate);
var_dump($diff/3600);
var_dump($dateinterval->d*24 + $dateinterval->h);
// int(33)
// int(34)
Expected result:
----------------
I would expect to always get 33 hours.
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=63953&edit=1
