Bug #79393 [PATCH]: Null coalescing operator failing with SplFixedArray

Edit report at https://bugs.php.net/bug.php?id=79393&edit=1 ID: 79393 Patch added by: cmb@php.net Reported by: julien dot falque at gmail dot com Summary: Null coalescing operator failing with SplFixedArray Status: Verified Type: Bug Package: SPL related Operating System: Linux PHP Version: 7.4.4RC1 Assigned To: cmb Block user comment: N Private report: N New Comment: The following pull request has been associated: Patch Name: Fix #79393: Null coalescing operator failing with SplFixedArray On GitHub: https://github.com/php/php-src/pull/5274 Patch: https://github.com/php/php-src/pull/5274.patch Previous Comments: ------------------------------------------------------------------------ [2020-03-18 12:59:31] julien dot falque at gmail dot com Description: ------------ This is probably related to https://bugs.php.net/bug.php?id=74478. Using null coalescing operation on an index that does not exist in an SplFixedArray triggers an exception (Index invalid or out of range) while doing the same with isset() works as expected. See the following snippets: * with isset(): https://3v4l.org/s79uA * with null coalescing operator: https://3v4l.org/ucSbZ For some reason, using a class that extends SplFixedArray and overrides method offsetExists() works: https://3v4l.org/5ohF1. Test script: --------------- <?php $foo = new SplFixedArray(2); $foo[0] = 'bar1'; $foo[1] = 'bar2'; var_dump($foo[0] ?? null); var_dump($foo[1] ?? null); var_dump($foo[2] ?? null); Expected result: ---------------- string(4) "bar1" string(4) "bar2" NULL Actual result: -------------- string(4) "bar1" string(4) "bar2" Fatal error: Uncaught RuntimeException: Index invalid or out of range in /in/ucSbZ:9 Stack trace: #0 {main} thrown in /in/ucSbZ on line 9 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79393&edit=1