php - register_shutdown_function not catch Fatal error: (Uncaught Error unset static property example, Call to undefined function prom())

Question

i have this:

1. i have An HTTACCESS file with directive to prepend a file for config and handle error: (it is mandatory: According to the documentation, this file must be attached before any other php script is executed in order to obtain errors: such as E_PARSE.)

   php_value auto_prepend_file "./server/conferror.php"
   

2. the content of conferror.php:

   <?php
   declare(strict_types=1);
   ini_set('session.gc_maxlifetime', '0');
   ini_set('session.use_only_cookies', '1');
   ini_set('session.cookie_httponly', '1');
   ini_set('allow_url_fopen', '1');
   ini_set('allow_url_include', '1');
   ini_set('error_reporting', '1');
   ini_set('display_errors', '0');
   error_reporting(E_ALL);
   set_error_handler("ErrorHandler");
   register_shutdown_function("ShutdownHandler");
   function ErrorHandler($error_level, $error_message, $error_file, $error_line, $error_context) {
       $ErrorHandler = "<b>File:</b> " . $error_file . '<br>' .
           "<b>Line :</b> " . $error_line . '<br>' .
           "<b>Desc:</b> <br>" . $error_message . '<br>';
       echo $ErrorHandler;
       exit;
   }
   function ShutdownHandler() {
       $CheckError = error_get_last();
       if ($CheckError != null) {
           $ErrorHandler = "<b>File:</b> " . $CheckError['file'] . '<br>' .
               "<b>Line :</b> " . $CheckError['line'] . '<br>' .
               "<b>Desc:</b> <br>" . $CheckError['message'] . '<br>';
           echo $ErrorHandler;
           exit;
       }
   }
   ?>
   

3. in my index.php i have this to start work the aplication:

   <?php
       require_once 'class.Main.php';
       $WebAPP = new CORE();
       $WebAPP->Main();
   ?>
   

4. in Main file i have a test, this code to unset a Static Object and Test Erros Handlers:

   <?php
   class CORE {
       public static $ObjClass;
       public function __construct() {
           self::$ObjClass['data']='data';
       }
       public function __destruct() {
           unset(CORE::$ObjClass);
       }
       public function Main() {
           #not Test on this.
       }
   }
   ?>
   

I have 3 questions:

1. Why Event handler does not capture the following error?

Fatal error: Uncaught Error: Attempt to unset static property CORE::$ObjClass in C:xampphtdocsdev2class.Main.php:8 Stack trace: #0 [internal function]: CORE->__destruct() #1 {main} thrown in C:xampphtdocsdev2class.Main.php on line 8

Second test:

This code:

<?php
class CORE {
    public function __construct() {
    }
    public function __destruct() {
        prom();
    }
    public function Main() {
        #not Test on this.
    }
}
?>

Generate this error:

Fatal error: Uncaught Error: Call to undefined function prom() in C:xampphtdocsdev2class.Main.php:6 Stack trace: #0 [internal function]: CORE->__destruct() #1 {main} thrown in C:xampphtdocsdev2class.Main.php on line 6

Update:

after much test i see that the error handler work fine with errors in declared function; but this not work in __construct or__destruct function.

Answer 1

1. Why i cant unset static property CORE::$ObjClass or self::$ObjClass?

Good question. I don't see anything in the official documentation of unset() or static properties that mentions this. But obviously you can't.

2. What is the right way to do it with static property?

You could just set it to NULL or an empty array.

3. Why Event handler does not capture the following error?

The documentation says:

The following error types cannot be handled with a user defined function: E_ERROR, E_PARSE, E_CORE_ERROR, E_CORE_WARNING, E_COMPILE_ERROR, E_COMPILE_WARNING, and most of E_STRICT raised in the file where set_error_handler() is called.

This error is presumably one of these types. I'm not sure how to tell specifically what its type is.

The shutdown function is being called, but for some reason error_get_last() is returning NULL rather than the information about this error.