ClearTest.php

<?php

declare (strict_types=1);
namespace Drupal\Tests\system\Functional\Cache;

use Drupal\Core\Cache\Cache;

/**
 * Tests our clearing is done the proper way.
 *
 * @group Cache
 */
class ClearTest extends CacheTestBase {
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        $this->defaultBin = 'render';
        $this->defaultValue = $this->randomMachineName(10);
        parent::setUp();
    }
    
    /**
     * Tests drupal_flush_all_caches().
     */
    public function testFlushAllCaches() : void {
        // Create cache entries for each flushed cache bin.
        $bins = Cache::getBins();
        $this->assertNotEmpty($bins, 'Cache::getBins() returned bins to flush.');
        foreach ($bins as $bin => $cache_backend) {
            $cid = 'test_cid_clear' . $bin;
            $cache_backend->set($cid, $this->defaultValue);
        }
        // Remove all caches then make sure that they are cleared.
        drupal_flush_all_caches();
        foreach ($bins as $bin => $cache_backend) {
            $cid = 'test_cid_clear' . $bin;
            $this->assertFalse($this->checkCacheExists($cid, $this->defaultValue, $bin), "All cache entries removed from {$bin}.");
        }
    }

}