Bug #74372 [Opn->Fbk]: autoloading file with syntax error uses next autoloader, may hide parse error

Edit report at https://bugs.php.net/bug.php?id=74372&edit=1 ID: 74372 Updated by: requinix@php.net Reported by: lightnb at bellsouth dot net Summary: autoloading file with syntax error uses next autoloader, may hide parse error -Status: Open +Status: Feedback Type: Bug Package: SPL related Operating System: Ubuntu 16.04 PHP Version: 7.0.17 Block user comment: N Private report: N New Comment: @lightnb: I had tried with the standard autoloader first. Same thing happens. The issue is in the autoloading process, not spl_autoload() itself. Fatal error: Uncaught ParseError: syntax error, unexpected end of file, expecting function (T_FUNCTION) in /root/php/PHP-7.0.17/widget.php:4 Stack trace: #0 [internal function]: spl_autoload('Widget') #1 /root/php/PHP-7.0.17/bug.php(15): spl_autoload_call('Widget') #2 {main} Next Exception: Could not autoload the class definition for "Widget" in /root/php/PHP-7.0.17/bug.php:10 Stack trace: #0 [internal function]: AutoLoadFallback('Widget') #1 /root/php/PHP-7.0.16/bug.php(15): spl_autoload_call('Widget') #2 {main} thrown in /root/php/PHP-7.0.17/bug.php on line 10 Bundling the exceptions is a bit unusual for PHP - normally it would be one error at a time - but I don't think there's any harm in it being there. An exception still gets thrown if one occurs, with the difference being that autoloading continues and therefore the class could still be loaded before the exception goes up the call stack. https://3v4l.org/IlUiA Previous Comments: ------------------------------------------------------------------------ [2017-04-04 23:12:19] lightnb at bellsouth dot net It seems like PHP should differentiate between a user-thrown exception and a parse error in a found file. (Although I'm still not sure what use-case would require autoload execution to continue after an exception is thrown, especially an exception throw by PHP's built-in autoloader.) ------------------------------------------------------------------------ [2017-04-04 21:33:15] nikic@php.net @requinix: I'd consider that a bug. If the first autoloader throws, the second one should not be executed. But ... it looks like this behavior was intentionally introduced some nine years ago: https://github.com/php/php-src/commit/e4869828a7905af350afe1870c64651578497a6c At this point this bug has probably become a "feature" :/ ------------------------------------------------------------------------ [2017-04-04 21:16:23] lightnb at bellsouth dot net The first call to spl_autoload_register(); should have no arguments to indicate the default loader should be tried first. You'll probably need to have an actual script with an actual second file that gets autoloaded in order to reproduce this. The issue does not occur if all calls to spl_autoload_register() have a function argument. It only occurs if you want to use the default autoloader in conjunction with a fallback handler. ------------------------------------------------------------------------ [2017-04-04 21:01:20] requinix@php.net I'm seeing the parse error just fine. https://3v4l.org/NSaTZ Are you catching the exception? Are you making sure to check for previous exceptions? https://3v4l.org/DXGtj ------------------------------------------------------------------------ [2017-04-04 20:31:06] lightnb at bellsouth dot net Description: ------------ Attempting to autoload a class file with a syntax error causes PHP to attempt to use the next autoloader rather than throwing the syntax error. Test script: --------------- // Use built in autoloader for 99% of loads spl_autoload_register(); // If that fails, see if it's a rare special case spl_autoload_register('AutoLoadFallback'); function AutoLoadFallback($ClassName){ // ... try stuff... throw new Exception('Could not autoload the class definition for "'.$ClassName.'"'); } // Try to load a new widget object $oWidget = new Widget(); Expected result: ---------------- In this case, assume that the Widget object has a file that the default autoloader can find, but the file contains a syntax error. The expected result would be a syntax error thrown for the faulty file. But what actually happens is, when an autoload file is found by the default autoload but a syntax error exists in it, PHP calls the next autoloader in the chain AutoLoadFallback, which of course throws an exception because it only handles cases that the default autoloader can't. The result is getting an exception thrown by the AutoLoadFallback function, rather than a parse error being thrown when the default autoloader tries to load the class. This blocks me from seeing the real error and line number. If I comment out the spl_autoload_register('AutoLoadFallback'); line, it throws a parse error per normal. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=74372&edit=1