Bug #66544 [Opn->Nab]: uasort works incorrent in some cases

Edit report at https://bugs.php.net/bug.php?id=66544&edit=1 ID: 66544 Updated by: rasmus@php.net Reported by: korovkin dot kirill at gmail dot com Summary: uasort works incorrent in some cases -Status: Open +Status: Not a bug Type: Bug Package: *General Issues Operating System: Linux 2.6.32-042stab07 PHP Version: 5.4.24 Block user comment: N Private report: N New Comment: Yup, the logic is wrong here. The sort function will compare them in this order: a = freeshipping, b = shipping a = tax_shipping, b = freeshipping a = discount, b = freeshipping a = tax_shipping, b = discount If you go through it one by one you will see that the first 3 checks all return 0, only the tax_shipping vs. discount is going to return -1 so those two elements are the only two affected. Previous Comments: ------------------------------------------------------------------------ [2014-01-22 18:38:09] mail at requinix dot net Looks like undefined behavior to me: your comparison function claims that discount == freeshipping and tax_shipping == freeshipping, yet tax_shipping < discount. Pick an unambiguous place for freeshipping to go, update the arrays so that your function can definitively state the sort order for every pairing, and it will sort correctly. Besides, allowing freeshipping to land wherever the sort happens to place it doesn't sound like a good idea. ------------------------------------------------------------------------ [2014-01-22 14:11:34] korovkin dot kirill at gmail dot com Description: ------------ You can see all information in the test script. Test script: --------------- $inputArray = array( 'shipping' => array( 'after' => array(), 'before' => array(), '_code' => 'shipping' ), 'freeshipping' => array( 'after' => array(), 'before' => array(), '_code' => 'freeshipping' ), 'discount' => array( 'after' => array('shipping', 'tax_shipping'), 'before' => array(), '_code' => 'discount' ), 'tax_shipping' => array( 'after' => array('shipping'), 'before' => array('discount'), '_code' => 'tax_shipping' ) ); function compare ($a, $b) { $aCode = $a['_code']; $bCode = $b['_code']; if (in_array($aCode, $b['after']) || in_array($bCode, $a['before'])) { $res = -1; } elseif (in_array($bCode, $a['after']) || in_array($aCode, $b['before'])) { $res = 1; } else { $res = 0; } return $res; } uasort($inputArray, 'compare'); var_dump(array_keys($inputArray)); Expected result: ---------------- array (size=4) 0 => string 'shipping' (length=8) 1 => string 'tax_shipping' (length=12) 2 => string 'discount' (length=8) 3 => string 'freeshipping' (length=12) Or another position for 'freeshipping'. But 'shipping' must be before 'tax_shipping' and 'discount' must be after 'tax_shipping'. Actual result: -------------- array (size=4) 0 => string 'tax_shipping' (length=12) 1 => string 'discount' (length=8) 2 => string 'freeshipping' (length=12) 3 => string 'shipping' (length=8) ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=66544&edit=1