From: php at sameprecision dot org
Operating system: irrelevant
PHP version: 5.2.5
PHP Bug Type: PCRE related
Bug description: preg_match_all makes extra matches on empty alternatives
Description:
------------
Performing a global match with empty alternative in subpattern followed by
$ alternative in subpattern results in "extra" match.
In the example below, I believe that preg_match_all should match the
second 'a' in the first subpattern, match the end of subject assertion in
the second subpattern and flag the global search as over.
I've tried this with php5.2.5/pcre7.3 on linux.
Reproduce code:
---------------
$regex = '/(a|)(,|$)/';
echo preg_match_all($regex, 'a,', $m1, PREG_SET_ORDER)."\n";
print_r($m1);
echo preg_match_all($regex, 'a,a' ,$m2, PREG_SET_ORDER)."\n";
print_r($m2);
Expected result:
----------------
2
Array
(
[0] => Array
(
[0] => a,
[1] => a
[2] => ,
)
[1] => Array
(
[0] =>
[1] =>
[2] =>
)
)
2
Array
(
[0] => Array
(
[0] => a,
[1] => a
[2] => ,
)
[1] => Array
(
[0] => a
[1] => a
[2] =>
)
)
Actual result:
--------------
2
Array
(
[0] => Array
(
[0] => a,
[1] => a
[2] => ,
)
[1] => Array
(
[0] =>
[1] =>
[2] =>
)
)
3
Array
(
[0] => Array
(
[0] => a,
[1] => a
[2] => ,
)
[1] => Array
(
[0] => a
[1] => a
[2] =>
)
[2] => Array
(
[0] =>
[1] =>
[2] =>
)
)
--
Edit bug report at http://bugs.php.net/?id=44463&edit=1
--
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=44463&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=44463&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=44463&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=44463&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=44463&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=44463&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=44463&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=44463&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=44463&r=support
Expected behavior: http://bugs.php.net/fix.php?id=44463&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=44463&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=44463&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=44463&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=44463&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=44463&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=44463&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=44463&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=44463&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=44463&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=44463&r=mysqlcfg
