Bug #72691 [NEW]: mb_ereg_search raises a warning if a match zero-width

From: ju1ius at laposte dot net Operating system: Debian Sid PHP version: 5.6.24 Package: mbstring related Bug Type: Bug Bug description:mb_ereg_search raises a warning if a match zero-width Description: ------------ when provided a pattern that produces a zero-width match (empty string), mb_ereg_search raises: `Warning: mb_ereg_search(): Empty regular expression`. First the warning is misleading, since it should not warn about an 'empty regular expression', but about a 'zero-width match'. More importantly this behavior is incorrect. A zero-width result is a perfectly valid match, and should never raise a warning. For example, matching the pattern '\A' at position zero should succeed without a warning, and the resulting position should be zero. Matching pattern '\s*' against the subject 'foo' at position 1 should succeed without a warning and the resulting position should be 1. Test script: --------------- <?php $str = 'foo'; mb_ereg_search_init($str); mb_ereg_search('\A'); var_dump(mb_ereg_search_getpos()); var_dump(mb_ereg_search_getregs()); mb_ereg_search('\s*'); var_dump(mb_ereg_search_getpos()); var_dump(mb_ereg_search_getregs()); mb_ereg_search('\w+'); var_dump(mb_ereg_search_getpos()); var_dump(mb_ereg_search_getregs()); mb_ereg_search('\Z'); var_dump(mb_ereg_search_getpos()); var_dump(mb_ereg_search_getregs()); Expected result: ---------------- int(0) array(1) { [0]=> string(0) "" } int(0) array(1) { [0]=> string(0) "" } int(3) array(1) { [0]=> string(0) "foo" } int(3) array(1) { [0]=> string(0) "" } Actual result: -------------- Warning: mb_ereg_search(): Empty regular expression in ... int(1) array(1) { [0]=> string(0) "" } Warning: mb_ereg_search(): Empty regular expression in ... int(2) array(1) { [0]=> string(0) "" } int(3) array(1) { [0]=> string(1) "o" } Warning: mb_ereg_search(): Empty regular expression in ... int(4) array(1) { [0]=> string(0) "" } -- Edit bug report at https://bugs.php.net/bug.php?id=72691&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=72691&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=72691&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=72691&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=72691&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=72691&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=72691&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=72691&r=needscript Try newer version: https://bugs.php.net/fix.php?id=72691&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=72691&r=support Expected behavior: https://bugs.php.net/fix.php?id=72691&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=72691&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=72691&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=72691&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=72691&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=72691&r=dst IIS Stability: https://bugs.php.net/fix.php?id=72691&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=72691&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=72691&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=72691&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=72691&r=mysqlcfg