Bug #70246 [Opn->Ver]: ArrayIterator skips next element when current element is unset in foreach.

Edit report at https://bugs.php.net/bug.php?id=70246&edit=1 ID: 70246 Updated by: cmb@php.net Reported by: arjen at react dot com Summary: ArrayIterator skips next element when current element is unset in foreach. -Status: Open +Status: Verified Type: Bug Package: SPL related Operating System: Linux PHP Version: 7.0.0beta3 Block user comment: N Private report: N New Comment: This regression has been introduced with commit 2b6a568[1]. The first change in array_015.phpt already shows the problem. [1] <http://git.php.net/?p=php-src.git;a=commit;h=2b6a568df119487f73abb43edd2ae82e83945356> Previous Comments: ------------------------------------------------------------------------ [2018-06-26 08:48:42] requinix@php.net Related To: Bug #76387 ------------------------------------------------------------------------ [2018-06-26 08:44:26] derick@php.net This bug is still being encountered in the wild, and it cost us considerable time to figure out what was wrong: https://github.com/mongodb/mongo-php-library/pull/544/files#diff-d4c8c6dc8769324fc27cfdac19f05cafR88 ------------------------------------------------------------------------ [2016-03-18 11:45:14] david at grudl dot com Similar bug with stdClass and ArrayIterator: https://3v4l.org/2A1pf ------------------------------------------------------------------------ [2015-09-19 18:55:50] j dot tvr at centrum dot cz This is probably not a bug. When you unset current element, the internal array pointer moves to the next element. Therefore what you're doing is essentially equivalent to https://3v4l.org/rWQq8: <?php $ar = [1, 2, 3, 4, 5]; $it = new ArrayIterator($ar); foreach ($it as $k => $v) { if ($k === 0) $it->next(); // eq. to unset($it[0]); echo "\$ar[$k] = $v;\n"; } echo "\n"; print_r(iterator_to_array($it)); ------------------------------------------------------------------------ [2015-08-18 11:56:39] arjen at react dot com Expected and actual result are swapped, my mistake.. Expected result: -------------- int(1) int(2) int(3) int(4) int(5) --------- int(1) int(3) int(4) int(5) Actual result: ---------------- int(1) int(2) int(4) int(5) --------- int(1) int(3) int(4) int(5) ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=70246 -- Edit this bug report at https://bugs.php.net/bug.php?id=70246&edit=1