These hooks can now be OOP in modules:
- hook_preprocess
- hook_preprocess_HOOK
Where HOOK is the name of a theme hook. (Which is not at all confusing.)
For template_preprocess_HOOK see https://www.drupal.org/node/3504125
The following two hooks are restricted to single implementations per module.
- hook_preprocess => #[Hook('preprocess')]
- hook_preprocess_HOOK => #[Hook('preprocess_HOOK')]
hook_preprocess
Before:
function contextual_preprocess(&$variables, $hook, $info): void {
After:
use Drupal\Core\Hook\Attribute\Hook;
#[Hook('preprocess')]
public function preprocess(&$variables, $hook, $info): void {hook_preprocess_HOOK
#[Hook] This should have a HOOK argument passed for the portion after module_preprocess_.
Before:
function comment_preprocess_block(&$variables): void {
After:
use Drupal\Core\Hook\Attribute\Hook;
#[Hook('preprocess_block')]
public function preprocessBlock(&$variables): void {Themes remain procedural.
In order to ensure that preprocess functions are not incorrectly ignored the hooks_converted parameter and StopProceduralScan attribute have been renamed https://www.drupal.org/node/3498595 for more information.
Backwards compatibility
For modules looking to support older versions of Drupal than 11.2 tag the procedural function with #[LegacyHook] and call the preprocess service.
Important note on 11.1 support
The minimum version for preprocess support in 11.1 is 11.1.8.
You must maintain the procedural implementation to support versions of Drupal lower than 11.2.0
To set the minimum version to 11.1.8 you can use ^11.1.8
Remember to set this minimum in both the info.yml and composer.json
Additional information
Further information can be found in Support for object oriented hook implementations using autowired services including information on how to maintain a single branch of a contrib module supporting Drupal versions before and after this change.
Original change record
Originally this issue provided a #[Preprocess] attribute, this has been removed https://www.drupal.org/node/3524585
