PDO::getAttribute() behaves differently than document

[SakiTakamachi]

Description

The following code:

<?php

// PDO::ERRMODE_SILENT
$pdo = new PDO('mysql:host=mysql;dbname=test;', 'root', '', [PDO::ATTR_ERRMODE => PDO::ERRMODE_SILENT]); // my env
var_dump($pdo->getAttribute(PDO::ATTR_TIMEOUT));

// PDO::ERRMODE_EXCEPTION
$pdo = new PDO('mysql:host=mysql;dbname=test;', 'root', ''); // my env
var_dump($pdo->getAttribute(PDO::ATTR_TIMEOUT));

Resulted in this output:

Warning: PDO::getAttribute(): SQLSTATE[IM001]: Driver does not support this function: driver does not support that attribute in /var/www/html/test/test_mysql.php on line 5
bool(false)

Fatal error: Uncaught PDOException: SQLSTATE[IM001]: Driver does not support this function: driver does not support that attribute in /var/www/html/test/test_mysql.php:9
Stack trace:
#0 /var/www/html/test/test_mysql.php(9): PDO->getAttribute(2)
#1 {main}
  thrown in /var/www/html/test/test_mysql.php on line 9

But I expected this output instead:

bool(null)
bool(null)

https://www.php.net/manual/en/pdo.getattribute.php#refsect1-pdo.getattribute-returnvalues

I suspect that the error/warning and returning false instead of null is probably just outdated documentation.
Even so, it is strange that warning is output with PDO::ERRMODE_SILENT.

I don't know if the documentation and the implementation need to be fixed, and if so, what should be fixed, so I would like your opinion.

PHP Version

PHP 8.1.22

Operating System

No response

[SakiTakamachi]

I got my expectations wrong. The correct is:

NULL
NULL

[SakiTakamachi]

@Girgias
I apologize for the inconvenience. I don't know who to mention regarding PDO...
Since you previously did a review related to PDO, I would like to use a mention.

[Girgias]

Considering there are user notes from 5 years ago that detail workarounds to catch exceptions, I suppose it is the intended behaviour, even if it is weird.

I think this is something that could be changed, but might require some discussion on the internals mailing list to gauge what people think is the correct behaviour.

[SakiTakamachi]

@Girgias
Thank you!

A few days ago, I submitted a proposal on the mailing list to deprecate PDO's error mode attribute.

But still no response from anyone...

I'll try replying to myself again.

[SakiTakamachi]

I plan to open an issue on doc, with the policy of modifying the document except for areas related to error modes.

[Girgias]

I think it is because your emails landed in most people's spam folder.

[SakiTakamachi]

Oh, sorry about that.

This morning in Japan time, I added SPF settings.

I'll wait and see if it will still be marked as spam in this state.