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drupal/core 11.4

ReplaceNonBoolAccessRector

Replace integer #access values with proper booleans in render arrays.

-$build = ['#markup' => 'foo', '#access' => 1];
+$build = ['#markup' => 'foo', '#access' => true];

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\ReplaceNonBoolAccessRector;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withRules([
        ReplaceNonBoolAccessRector::class,
    ]);

Other rules in the drupal/core 11.4 set