[wp-trac] [WordPress Trac] #25002: get_post_time() doesn't return correct GMT time if date_default_timezone_set is changed from UTC.

[WordPress Trac]

#25002: get_post_time() doesn't return correct GMT time if
date_default_timezone_set is changed from UTC.
--------------------------+-----------------------------
 Reporter:  johnregan3    |      Owner:
     Type:  defect (bug)  |     Status:  new
 Priority:  normal        |  Milestone:  Awaiting Review
Component:  Date/Time     |    Version:  3.6
 Severity:  normal        |   Keywords:  has-patch
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 get_post_time() and get_post_modified_time() have a parameter for GMT(UTC)
 time.  However, they use mysqldate(), which does not take such a parameter
 (i.e., mysql2date expects the default time zone to be UTC).

 mysql2date() uses strtotime() or date(), both of which return values
 relative to the default time zone (date_default_timezone_set()).  So, if a
 developer changes the default timezone and then requests a GMT date from
 get_post_time() or get_post_modified_time(), they will receive an
 erroneous return value.

 More information here: [http://weston.ruter.net/2013/04/02/do-not-change-
 the-default-timezone-from-utc-in-wordpress/]

 To reproduce the problem, run the enclosed unit test.  It requests a GMT
 time from the function twice:  once while in GMT, and once in another
 timezone (America/Chicago).  The two results should be identical because
 they both request GMT time, but they are not.

 Just to confirm, this problem occurs when all plugins are deactivated and
 the default theme is used.

 I am submitting two files with this ticket:

 1.  A Unit Test (mysql2date.php) displaying the faults in mysql2date (and
 showing that the new patch fixes the issue).

 2.  A Patch to fix the bug.  This patch has been tested using the Unit
 Test above.

 The patch begins by adding a fourth optional parameter to mysql2date,
 $gmt, which will tell the function that it needs to return a GMT value.
 This $gmt variable will be sent from get_post_time() and
 get_post_modified_time().  Then, if GMT is requested, the
 date_default_timezone_set is set to UTC (WP's default timezone), then
 conditional statements instruct mysql2date as to what value to return.
 There is more documentation within the patch itself.

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Ticket URL: <http://core.trac.wordpress.org/ticket/25002>
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