PHP 8.4 compatibility

[cedric-anne]

Q	A
Bug fix?	no
New feature?	yes
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	-

The following dependencies patches were proposed but are not yet all validated or released.

• Fix PHP 8.4 deprecations apereo/phpCAS#444
• Fix PHP 8.4 deprecations atoum/atoum#899
• Fix PHP 8.4 deprecations atoum/stubs#24
• Fix deprecations on PHP 8.4 thephpleague/event#107
• Explicitly mark nullable parameter thephpleague/oauth2-client#1034
• Add PHP 8.4 support thephpleague/oauth2-server#1440
• Fix PHP 8.4 deprecations sabre-io/dav#1560
• Fix Implicitly marking parameter $param as nullable is deprecated sabre-io/vobject#673
• Add PHP 8.4 support swaggest/json-diff#69
• Fix PHP 8.4 deprecations swaggest/php-json-schema#163
• [Cache] Fix compatibility with Redis 6.1.0 pre-releases symfony/symfony#58169
• Add support for PHP 8.4 friendsoftwig/twigcs#332
• Fix PHP 8.4 deprecations wapmorgan/UnifiedArchive#47

[cedric-anne]

I changed the error reporting level in our test suite to not report deprecations. I have done this because I spend too much time on every new PHP version to report/fix the deprecated usages in the vendor libraries.

The lint task will still be able to detect most deprecations (see https://github.com/glpi-project/glpi/actions/runs/12029123283/job/33533716142?pr=17786). We may miss some of them, for instance the deprecations triggered when a param has a specific value, but not fixing them ASAP is not an issue. Indeed, they are supposed to have no functional impact and we will anyway be able to detect and fix them when it will be a real issue, i.e. when we will work on a new PHP major version (next will be PHP 9.0 and is still not planned).

We may put back the deprecations report in our test suite later, but it requires either to refactor our error handler (for instance to filter the reports depending on their backtrace, and that may be complex), or completely remove our usage of atoum and use the ignoreIndirectDeprecations=true PHPUnit configuration.

The only library I had to patch is the apereo/phpcas library because it is always loaded early due to https://github.com/apereo/phpCAS/blob/690d431005e4f88651499458469536201623b057/composer.json#L35-L36 and was therefore triggering the deprecation before the error reporting level setting, and that was causing the failure of our test suite.