Bug #53724 [Com]: array_diff like methods compares false as identity and true as equal

2011-02-21 Thread lukas dot starecek at centrum dot cz
Edit report at http://bugs.php.net/bug.php?id=53724edit=1

 ID: 53724
 Comment by: lukas dot starecek at centrum dot cz
 Reported by:lukas dot starecek at centrum dot cz
 Summary:array_diff like methods compares false as identity
 and true as equal
 Status: Open
 Type:   Bug
 Package:Arrays related
 Operating System:   Irrelevant
 PHP Version:5.3.5
 Block user comment: N
 Private report: N

 New Comment:

Ah I did not noticed this grey part of method documentation in
examples. You are right, documentation says it, but imho in not so clear
way. I have read only specifications, not examples. Imho documentation
could be a little bit more exact, because this is important.



So sadly this functions are designed only for string comparison, not for
general variable comparison :-/ .



My fault, bogus, sorry. But think about functions of this kind for
general variables comparison, not only for string comparison :-) .


Previous Comments:

[2011-02-20 16:20:18] tbrasta at gmail dot com

This is not a bug. The function is operating exactly as stated in the
documentation, i.e. casted to string values are compared. Since (string)
0 = 0, (string) false =  and (string) 0 = 0 but 0 !== , you
get the result as it should be.


[2011-01-12 14:27:34] lukas dot starecek at centrum dot cz

A little mistake, '' behaves as same with false, so problem is only in
comparing 0 and '0' (and maybee some other variables I did not used).


[2011-01-12 14:16:39] lukas dot starecek at centrum dot cz

Description:

array_diff functions compares boolean false as identity (operator ===)
and boolean true as equal (operator ==) so behaves inconsistently. It
should compare all values in same way and in my opinion it should
compare as equals (==) or have argument (or another mechanism) how to
set whether compare by equal or identity.



As example I use array_diff_assoc but I think it will probably behave
simmilary with another array realted functions (array_diff%,
array_intersect%). In expected result I suppose comparing as equal
(operator '==').



In example you can see, that array_diff_assoc behaves in such way that 0
or '0' or '' is not same as false, but 1 or '1' is same as true. So
false is compared like '===' and true is compared like '=='. Because 0
is same as '0' and 1 is same as '1' I suppose, that this problem is only
for boolean false value.



Test script:
---
$arr1 = array('a' = 0, 'b' = 1,'c' = '0',   'd' = '1',  'e'
= '','f' = false, 'g' = true, 'h' = 0,   'i' = 1);

$arr2 = array('a' = false, 'b' = true, 'c' = false, 'd' = true, 'e'
= false, 'f' = false, 'g' = true, 'h' = '0', 'i' = '1');



var_dump(array_diff_assoc($arr1, $arr2));

Expected result:

array(0) {

}



Actual result:
--
array(2) {

  [a]=

  int(0)

  [c]=

  string(1) 0

}








-- 
Edit this bug report at http://bugs.php.net/bug.php?id=53724edit=1


Bug #53724 [Com]: array_diff like methods compares false as identity and true as equal

2011-02-20 Thread tbrasta at gmail dot com
Edit report at http://bugs.php.net/bug.php?id=53724edit=1

 ID: 53724
 Comment by: tbrasta at gmail dot com
 Reported by:lukas dot starecek at centrum dot cz
 Summary:array_diff like methods compares false as identity
 and true as equal
 Status: Open
 Type:   Bug
 Package:Arrays related
 Operating System:   Irrelevant
 PHP Version:5.3.5
 Block user comment: N
 Private report: N

 New Comment:

This is not a bug. The function is operating exactly as stated in the
documentation, i.e. casted to string values are compared. Since (string)
0 = 0, (string) false =  and (string) 0 = 0 but 0 !== , you
get the result as it should be.


Previous Comments:

[2011-01-12 14:27:34] lukas dot starecek at centrum dot cz

A little mistake, '' behaves as same with false, so problem is only in
comparing 0 and '0' (and maybee some other variables I did not used).


[2011-01-12 14:16:39] lukas dot starecek at centrum dot cz

Description:

array_diff functions compares boolean false as identity (operator ===)
and boolean true as equal (operator ==) so behaves inconsistently. It
should compare all values in same way and in my opinion it should
compare as equals (==) or have argument (or another mechanism) how to
set whether compare by equal or identity.



As example I use array_diff_assoc but I think it will probably behave
simmilary with another array realted functions (array_diff%,
array_intersect%). In expected result I suppose comparing as equal
(operator '==').



In example you can see, that array_diff_assoc behaves in such way that 0
or '0' or '' is not same as false, but 1 or '1' is same as true. So
false is compared like '===' and true is compared like '=='. Because 0
is same as '0' and 1 is same as '1' I suppose, that this problem is only
for boolean false value.



Test script:
---
$arr1 = array('a' = 0, 'b' = 1,'c' = '0',   'd' = '1',  'e'
= '','f' = false, 'g' = true, 'h' = 0,   'i' = 1);

$arr2 = array('a' = false, 'b' = true, 'c' = false, 'd' = true, 'e'
= false, 'f' = false, 'g' = true, 'h' = '0', 'i' = '1');



var_dump(array_diff_assoc($arr1, $arr2));

Expected result:

array(0) {

}



Actual result:
--
array(2) {

  [a]=

  int(0)

  [c]=

  string(1) 0

}








-- 
Edit this bug report at http://bugs.php.net/bug.php?id=53724edit=1