set_exception_handler must catch exceptions also when in shutdown

[mvorisek]

Description

The following code:

click to expand

<?php

set_exception_handler(function (\Throwable $exception) {
    echo 'Caught: ' . $exception->getMessage() . "\n";
});

set_error_handler(static function (int $severity, string $msg, string $file, int $line): bool {
    echo 'Caught error: ' . $msg . "\n";
    return true;
});

register_shutdown_function(function () {
    trigger_error('warn_shutdown_1', \E_USER_WARNING);
});

register_shutdown_function(function () {
    trigger_error('warn_shutdown_2', \E_USER_WARNING);
});

register_shutdown_function(function () {
    throw new \Exception('ex_shutdown_1');
});

register_shutdown_function(function () {
    // expected to be never executed as after 1 uncaught exception php invokes shutdown,
    // after 1 uncaught exception in shutdown, php terminates
    throw new \Exception('ex_shutdown_2');
});

trigger_error('warn_regular_1', \E_USER_WARNING);
trigger_error('warn_regular_2', \E_USER_WARNING);

throw new \Exception('ex_regular');

https://3v4l.org/U5sF8

Resulted in this output:

Caught error: warn_regular_1
Caught error: warn_regular_2
Caught: ex_regular
Caught error: warn_shutdown_1
Caught error: warn_shutdown_2

Fatal error: Uncaught Exception: ex_shutdown_1 in /in/lXRcY:24
Stack trace:
#0 [internal function]: {closure}()
#1 {main}
  thrown in /in/lXRcY on line 24

But I expected this output instead:

Caught error: warn_regular_1
Caught error: warn_regular_2
Caught: ex_regular
Caught error: warn_shutdown_1
Caught error: warn_shutdown_2
Caught: ex_shutdown_1

restore_error_handler is working in shutdown, set_exception_handler must work too

PHP Version

any

Operating System

any

[Girgias]

I don't think this makes any sense whatsoever.

It like you are expecting:

try {
    function_1_that_throw();
    function_2_that_throw();
} catch (\Throwable $e) {
    echo "Caught exception";
}

To execute both function_1_that_throw() and function_2_that_throw(). Which is clearly nonsensical.

But wondering what other people think about this @iluuu1994 @arnaud-lb @kocsismate .

[mvorisek]

@Girgias this issue is about set_exception_handler to work in register_shutdown_function - simpler demo https://3v4l.org/nHlKr

[Girgias]

I still don't think this is particularly sensible, we are re-entering the VM, which may be in an unstable state. But I'll let other people judge as I don't deal with the shutdown part that much.