1--TEST-- 2usort() in combination with "Call to a member function method() on null" 3--FILE-- 4<?php 5set_error_handler(function($code, $message) { 6 var_dump($code, $message); 7}); 8 9$comparator= null; 10$list= [1, 4, 2, 3, -1]; 11usort($list, function($a, $b) use ($comparator) { 12 try { 13 return $comparator->compare($a, $b); 14 } catch (Error $e) { 15 var_dump($e->getCode(), $e->getMessage()); 16 return 0; 17 } 18}); 19var_dump($list); 20echo "Alive\n"; 21?> 22--EXPECTF-- 23int(0) 24string(43) "Call to a member function compare() on null" 25int(0) 26string(43) "Call to a member function compare() on null" 27int(0) 28string(43) "Call to a member function compare() on null" 29int(0) 30string(43) "Call to a member function compare() on null" 31array(5) { 32 [0]=> 33 int(1) 34 [1]=> 35 int(4) 36 [2]=> 37 int(2) 38 [3]=> 39 int(3) 40 [4]=> 41 int(-1) 42} 43Alive 44