PDOException::getCode() return value type is string

[Yurunsoft]

Description

The following code:

<?php

declare(strict_types=1);

try
{
    $pdo = new PDO('mysql:host=127.0.0.1', 'root', 'root');
    $pdo->query('select x');
}
catch (\Throwable $e)
{
    var_dump($e->getCode());
    throw new \Exception($e->getMessage(), $e->getCode(), $e);
}

Resulted in this output:

string(5) "42S22"
PHP Fatal error:  Uncaught TypeError: Exception::__construct(): Argument #2 ($code) must be of type int, string given in /mnt/d/projects/imi/imi-2.1/test.php:13
Stack trace:
#0 /mnt/d/projects/imi/imi-2.1/test.php(13): Exception->__construct()
#1 {main}
  thrown in /mnt/d/projects/imi/imi-2.1/test.php on line 13

But I expected this output instead:

string(5) "42S22"
PHP Fatal error:  Uncaught PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'x' in 'field list' in /mnt/d/projects/imi/imi-2.1/test.php:8
Stack trace:
#0 /mnt/d/projects/imi/imi-2.1/test.php(8): PDO->query()
#1 {main}

Next Exception: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'x' in 'field list' in /mnt/d/projects/imi/imi-2.1/test.php:13
Stack trace:
#0 {main}
  thrown in /mnt/d/projects/imi/imi-2.1/test.php on line 13

---

Is it possible to change the return value of Throwable::getCode() to int|string?

php-src/Zend/zend_exceptions.stub.php

Line 12 in eb22f1a

public function getCode(); // TODO add proper type (i.e. int|string)

PHP Version

8.0.21

Operating System

Ubuntu 20.04

[damianwadley]

I like how the top two comments on the PDOException page, 12 and 8 years old respectively, both talk about how the $code is a string instead of an int.
https://www.php.net/manual/en/class.pdoexception.php

Making Throwable's $code be an int|string is only the first step. It's also a big step, one that may need to wait until PHP 9.0. But I think the change is a good idea, as there's really no particular need for the "code" to be a number - anything could work, from opaque identifiers to hashes or GUIDs, depending on what the exception considers to be a "code". I've had to face that situation myself many times.

But there is the alternative to consider, which is also breaking but in a far smaller scope: PDOException could be fixed to put its SQLSTATE code into a new variable and method, say $sqlStateCode/getSqlStateCode, instead of using $code/getCode for it.