#48824 [Bgs]: dateTime->add() doesn't properly account for days past the end of months

ID: 48824 User updated by: brad at omnis dot com Reported By: brad at omnis dot com Status: Bogus Bug Type: Date/time related Operating System: Linux (CentOS 5.3) PHP Version: 5.3.0 New Comment: Just to be clear, because the PHP devs don't want to write correct code and would rather rely on a broken library, this bug gets marked as bogus and everyone has to deal with an inferior date function. To point out that my idea of date math is not incorrect, here is postgresql (also tested in MySQL and Oracle which provide the same results): query: select '01-31-2009 23:59:59'::timestamp + '1 month'::interval result: 2009-02-28T23:59:59 Previous Comments: ------------------------------------------------------------------------ [2009-08-06 13:35:24] jani@php.net DateInterval uses the same parser as strtotime(). ------------------------------------------------------------------------ [2009-07-07 16:56:59] brad at omnis dot com From a brief reading of the source code, dateTime->add() doesn't *appear* use the underlying strtotime library, so I don't see why this function should be forced to have the same weakness of that function. IMO, these date functions would be far more useful if they adhere to common date manipulation ideals instead of using simple math as they are currently doing. As it stands now, the dateTime->add() function cannot be relied upon for any sort of accounting math and IMO completely defeats the purpose of specialized dateTime functions. ------------------------------------------------------------------------ [2009-07-07 09:50:48] sjoerd-php at linuxonly dot nl Thank you for your report. The issue you report is not a bug. See also bug #43999. ------------------------------------------------------------------------ [2009-07-06 22:24:39] brad at omnis dot com Description: ------------ dateTime->add(dateInterval) isn't applying proper calendar math when adding intervals. Reproduce code: --------------- $dateTest = new dateTime('2008-01-31',new dateTimeZone("GMT")); print_r($dateTest); $dateTest->add(new dateInterval('P1M')); print_r($dateTest); Expected result: ---------------- DateTime Object ( [date] => 2008-01-31 00:00:00 [timezone_type] => 3 [timezone] => UTC ) DateTime Object ( [date] => 2008-02-28 00:00:00 [timezone_type] => 3 [timezone] => UTC ) Actual result: -------------- DateTime Object ( [date] => 2008-01-31 00:00:00 [timezone_type] => 3 [timezone] => UTC ) DateTime Object ( [date] => 2008-03-02 00:00:00 [timezone_type] => 3 [timezone] => UTC ) ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=48824&edit=1