Doc #74569 [Opn]: Return in a finally clause silently ignores an exception thrown in a try clause

Edit report at https://bugs.php.net/bug.php?id=74569&edit=1 ID: 74569 Updated by: requinix@php.net Reported by: trianman at gmail dot com Summary: Return in a finally clause silently ignores an exception thrown in a try clause Status: Open Type: Documentation Problem Package: Scripting Engine problem Operating System: Any PHP Version: 7.1.4 Block user comment: N Private report: N New Comment: @anhlephuoc: The behavior you're seeing is because the "fatal error" from the undefined function call is actually an exception that extends Error, not an exception that extends Exception. You aren't catching it which means normally it would have been thrown - if not for the fact that your finally block overrides that behavior and returns a value instead. As of PHP 7, "catch (Exception $e)" does not catch every single exception that could be thrown. Use the Throwable interface for that. https://3v4l.org/6N4d9 Previous Comments: ------------------------------------------------------------------------ [2020-11-22 19:16:11] anhlephuoc at gmail dot com This faulty behaviour of the return statement in the finally{} of the the try{} block extends beyond the catchable error/exceptions. 1%0; // No warning or error. unknown_function(); // not reported. Program not aborted It took me days to locate a misspelled function, because no error is reported at all and program would normally abort, now continue with undesirable behaviour. Example code: <?php error_reporting(E_ALL|E_STRICT); function do_test(): int { try { 1/0; // a warning in php 7 - reported as documented nonexistent_function(); // a fatal error - not reported - program continues 1%0; // a fatal error return 0; } catch (Exception $e) { printf("CATCH\n"); return 1; } finally { printf("FINALLY\n"); return 2; } return 3; } printf("%d\n", do_test()); ------------------------------------------------------------------------ [2017-05-16 21:16:02] danack@php.net The Php Inspections (EA Extended) guy has added this as code smell to that tool. You could consider using that tool and giving them some money for being so nice: https://www.indiegogo.com/projects/php-inspections-ea-extended-a-code-analyzer-security#/ ------------------------------------------------------------------------ [2017-05-14 19:09:19] cmb@php.net It seems to me this is simply a documentation issue. ------------------------------------------------------------------------ [2017-05-12 18:24:10] trianman at gmail dot com 2 danack@php.net Sorry, I don't want to be mean. My English skills are not very good and it is sometimes hard to express my thoughts in a clear way. I've just realized that the finally statement is some-kind of antipattern for me. Because finally is a shortcut for catching and re-throwing an \Exception class eg. <?php try { throw new CustomException(); } catch (CustomException $ex) { handleException(); } catch (\Exception $ex) { doThingsInFinally(); throw $ex; } doThingsInFinally(); ?> Or with finally: <?php try { throw new CustomException(); } catch (CustomException $ex) { handleException(); } finally { doThingsInFinally(); } ?> Of cause if we have a return statement instead of a doTihingsInFinally() method, we will lose an exception. But we doing it in a clear way. On the other hand finally statement hides out from developer's eyes what actually is going. So for my mind a little copy-paste is a lesser evil than an unclear behavior. For all other guys the E_NOTICE will be enough. (: ------------------------------------------------------------------------ [2017-05-11 14:28:34] olavisau at gmail dot com BC is broken with any solution. The fact that javascript behaves in the same way worries me. It's probably very hard to implement. I agree with the E_NOTICE. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=74569 -- Edit this bug report at https://bugs.php.net/bug.php?id=74569&edit=1