Edit report at https://bugs.php.net/bug.php?id=70763&edit=1
ID: 70763
Comment by: panguzol at gmail dot com
Reported by: jonjohnson1 at yandex dot com
Summary: Bug in array_udiff()?
Status: Open
Type: Bug
Package: *General Issues
Operating System: Windows
PHP Version: 5.6.14
Block user comment: N
Private report: N
New Comment:
Test code
```
<?php
$a = [1,2,3,4,5];
$b = [2,3,5];
echo '#1 ';
$r = array_udiff($a, $b, function($x, $y) {
return $x === $y ? 0 : -1;
});
var_dump($r);
echo '<br />';
echo '#2 ';
$r = array_udiff($a, $b, function($x, $y) {
return $x === $y ? 0 : 1;
});
var_dump($r);
echo '<br />';
echo '#3 ';
$r = array_udiff($a, $b, function($x, $y) {
return $x - $y;
});
var_dump($r);
echo '<br />';
echo '#4 ';
$r = array_udiff($a, $b, function($x, $y) {
return $y - $x;
});
var_dump($r);
echo '<br />';
echo '#5 ';
$r = array_udiff($a, $b, function($x, $y) {
return (int)!$x === $y;
});
var_dump($r);
?>
```
Expected output:
```
#1 array(2) { [0]=> int(1) [3]=> int(4) }
#2 array(2) { [0]=> int(1) [3]=> int(4) }
#3 array(2) { [0]=> int(1) [3]=> int(4) }
#4 array(2) { [0]=> int(1) [3]=> int(4) }
#5 array(2) { [0]=> int(1) [3]=> int(4) }
```
Actual output
```
#1 array(2) { [0]=> int(1) [3]=> int(4) }
#2 array(5) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) }
#3 array(2) { [0]=> int(1) [3]=> int(4) }
#4 array(2) { [0]=> int(1) [3]=> int(4) }
#5 array(0) { }
```
As we can see in cases #2 and #5 we got wrong result.
PS: Why comparison function must return integer not boolean? It shouldn't make difference
whether other element is bigger or smaller, just is it equal or not.
Previous Comments:
------------------------------------------------------------------------
[2015-10-21 21:16:04] jonjohnson1 at yandex dot com
Description:
------------
function value_compare_func($a, $b){
if ($a === 'n_3') {
return 0;
}
return 1;
}
$array1 = array("n_1", "n_2", "n_3", "n_4" );
$array2 = array("green");
$result = array_udiff($array1, $array2, "value_compare_func");
print_r($result);
The expected output is:
Array([0] => 'n_1', [1] => 'n_2' , [3] => 'n_4' )
But PHP outputs:
Array([1] => 'n_2' , [3] => 'n_4' )
Where is n_1?
Test script:
---------------
$array1 = array("n_1", "n_2", "n_3", "n_4" );
$array2 = array("green");
$result = array_udiff($array1, $array2, "value_compare_func");
print_r($result);
Expected result:
----------------
Array([0] => 'n_1', [1] => 'n_2' , [3] => 'n_4' )
Actual result:
--------------
Array([1] => 'n_2' , [3] => 'n_4' )
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=70763&edit=1