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Configurable

SystemRegionFunctionsRector

Replace deprecated system_region_list() and system_default_region() with Theme object methods via the theme_handler service.

-system_region_list($theme);
+\Drupal::service('theme_handler')->getTheme($theme)->listAllRegions();

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\SystemRegionFunctionsRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(SystemRegionFunctionsRector::class, [
        new DrupalIntroducedVersionConfiguration('11.4.0'),
    ]);

-system_region_list($theme, REGIONS_VISIBLE);
+\Drupal::service('theme_handler')->getTheme($theme)->listVisibleRegions();

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\SystemRegionFunctionsRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(SystemRegionFunctionsRector::class, [
        new DrupalIntroducedVersionConfiguration('11.4.0'),
    ]);

-system_default_region($theme);
+\Drupal::service('theme_handler')->getTheme($theme)->getDefaultRegion();

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\SystemRegionFunctionsRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(SystemRegionFunctionsRector::class, [
        new DrupalIntroducedVersionConfiguration('11.4.0'),
    ]);