Bug #73427 [NEW]: Unintended behaviour of intersection functions

From: turabgarip at gmail dot com Operating system: Windows PHP version: 5.6.27 Package: Arrays related Bug Type: Bug Bug description:Unintended behaviour of intersection functions Description: ------------ Intersection functions intend to compute the intersection of two or more arrays; but they try to compare the elements of the individual array itself. This is contradictory to the logic of intersection. Thus it makes the intersection functions considerably slow. In the test script, there are two arrays. Intersection will start to compare from the first three colors like; "blue" to "green", "black" to "blue"; that are, the elements of the first array only; which are actually very unnecessary to compare. Because the actual intention is to compute the intersection of the two arrays; not the intersection of the elements of the array itself. However an array can contain only one identical element at once anyway, so it's useless and resource consuming to check the array's own elements against each other. Test script: --------------- $arr1 = array('green', 'blue', 'black'); $arr2 = array('yellow', 'red', 'cyan'); array_intersect($arr1, $arr2); Expected result: ---------------- Intersection function should compare the elements of the given arrays crosswise. -- Edit bug report at https://bugs.php.net/bug.php?id=73427&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=73427&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=73427&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=73427&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=73427&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=73427&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=73427&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=73427&r=needscript Try newer version: https://bugs.php.net/fix.php?id=73427&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=73427&r=support Expected behavior: https://bugs.php.net/fix.php?id=73427&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=73427&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=73427&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=73427&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=73427&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=73427&r=dst IIS Stability: https://bugs.php.net/fix.php?id=73427&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=73427&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=73427&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=73427&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=73427&r=mysqlcfg