Bug #61526 [NEW]: is_subclass_of(string, string, false) always returns false

From: Operating system: Debian PHP version: 5.3.10 Package: Class/Object related Bug Type: Bug Bug description:is_subclass_of(string, string, false) always returns false Description: ------------ According to the documentation ( http://php.net/manual/en/function.is-subclass-of.php ) the third parameter of is_subclass_of decides "Whether to call autoloader if the class doesn't exist." That means that is_subclass_of('class1', 'class2', false) should - return true if class1 is loaded and a subclass of class2 - return false if class1 is loaded but not a subclass of class2 - return false if class1 is not loaded What actually happens is that it always returns false, no matter what. The naming of the parameter - "$allow_string" - suggests this is somewhat intentional, but it is a completely unintuitive and unhelpful behavior, which makes the option completely useless: is_subclass_of with $allow_string set to false becomes worthless if the first argument is a string, and if it is an object, the third parameter is pointless again as the class must have been loaded already. Test script: --------------- class Super {} class Sub extends Super {} var_dump(is_subclass_of('Sub', 'Super')); // true var_dump(is_subclass_of('Sub', 'Super'), false); // should be true but false -- Edit bug report at https://bugs.php.net/bug.php?id=61526&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=61526&r=trysnapshot54 Try a snapshot (PHP 5.3): https://bugs.php.net/fix.php?id=61526&r=trysnapshot53 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=61526&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=61526&r=fixed Fixed in SVN and need be documented: https://bugs.php.net/fix.php?id=61526&r=needdocs Fixed in release: https://bugs.php.net/fix.php?id=61526&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=61526&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=61526&r=needscript Try newer version: https://bugs.php.net/fix.php?id=61526&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=61526&r=support Expected behavior: https://bugs.php.net/fix.php?id=61526&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=61526&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=61526&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=61526&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=61526&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=61526&r=dst IIS Stability: https://bugs.php.net/fix.php?id=61526&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=61526&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=61526&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=61526&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=61526&r=mysqlcfg