Bug #76554 [NEW]: DateTimeImmutable::format() returns invalid result for DST date time

From: learncomp at mail dot ru Operating system: Linux, 4.16.13-2-ARCH PHP version: 7.3.0alpha2 Package: Date/time related Bug Type: Bug Bug description:DateTimeImmutable::format() returns invalid result for DST date time Description: ------------ Europe/Oslo has DST and it occurs at (got with `(new DateTimeZone("Europe/Oslo"))->getTransitions()`): ``` [ "ts" => 1521939600, "time" => "2018-03-25T01:00:00+0000", "offset" => 7200, "isdst" => true, "abbr" => "CEST", ], [ "ts" => 1540688400, "time" => "2018-10-28T01:00:00+0000", "offset" => 3600, "isdst" => false, "abbr" => "CET", ], ``` The following test script increments the input date time to 1 hour which should not occur?. I'm not sure either this is a bug or not as I don't have enough information to decide but probably it can be the bug. Test script: --------------- <?php // For the start date time + 1 hour it prints 2018-03-25 03:00:00, which is incorrect? echo (new \DateTimeImmutable('2018-03-25 02:00:00', new \DateTimeZone('Europe/Oslo')))->format('Y-m-d H:i:s'); // However for the end date time it does not change the value, tried for the dates: "2018-10-27 23:00:00", "2018-10-28 00:00:00", "2018-10-28 01:00:00", "2018-10-28 02:00:00", "2018-10-28 03:00:00", "2018-10-28 04:00:00", "2018-10-28 05:00:00", "2018-10-28 06:00:00" like so: // echo (new \DateTimeImmutable('2018-10-28 03:00:00', new \DateTimeZone('Europe/Oslo')))->format('Y-m-d H:i:s'); // It always returns the same value, which I think is correct. Expected result: ---------------- 2018-03-25 02:00:00 Actual result: -------------- 2018-03-25 03:00:00 -- Edit bug report at https://bugs.php.net/bug.php?id=76554&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=76554&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=76554&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=76554&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=76554&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=76554&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=76554&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=76554&r=needscript Try newer version: https://bugs.php.net/fix.php?id=76554&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=76554&r=support Expected behavior: https://bugs.php.net/fix.php?id=76554&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=76554&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=76554&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=76554&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=76554&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=76554&r=dst IIS Stability: https://bugs.php.net/fix.php?id=76554&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=76554&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=76554&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=76554&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=76554&r=mysqlcfg