class InstallerIsolationLevelExistingSettingsTest

class InstallerIsolationLevelExistingSettingsTest extends InstallerExistingSettingsTest {
    
    /**
     * {@inheritdoc}
     */
    protected function prepareEnvironment() {
        parent::prepareEnvironment();
        $connection_info = Database::getConnectionInfo();
        // The isolation_level option is only available for MySQL.
        if ($connection_info['default']['driver'] !== 'mysql') {
            $this->markTestSkipped("This test does not support the {$connection_info['default']['driver']} database driver.");
        }
    }
    
    /**
     * Verifies that isolation_level is not set in the database settings.
     */
    public function testInstaller() : void {
        $contents = file_get_contents($this->container
            ->getParameter('app.root') . '/' . $this->siteDirectory . '/settings.php');
        // Test that isolation_level was not set.
        $this->assertStringNotContainsString("'isolation_level' => 'READ COMMITTED'", $contents);
        $this->assertStringNotContainsString("'isolation_level' => 'REPEATABLE READ'", $contents);
        // Change the default database connection to use the isolation level from
        // the test.
        $connection_info = Database::getConnectionInfo();
        $driver_test_connection = $connection_info['default'];
        // We have asserted that the isolation level was not set.
        unset($driver_test_connection['isolation_level']);
        unset($driver_test_connection['init_commands']);
        Database::renameConnection('default', 'original_database_connection');
        Database::addConnectionInfo('default', 'default', $driver_test_connection);
        // Close and reopen the database connection, so the database init commands
        // get executed.
        Database::closeConnection('default', 'default');
        $connection = Database::getConnection('default', 'default');
        $query = 'SELECT @@SESSION.tx_isolation';
        // The database variable "tx_isolation" has been removed in MySQL v8.0 and
        // has been replaced by "transaction_isolation".
        // @see https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_tx_isolation
        if (!$connection->isMariaDb() && version_compare($connection->version(), '8.0.0-AnyName', '>')) {
            $query = 'SELECT @@SESSION.transaction_isolation';
        }
        // Test that transaction level is REPEATABLE READ.
        $this->assertEquals('REPEATABLE-READ', $connection->query($query)
            ->fetchField());
        // Restore the old database connection.
        Database::addConnectionInfo('default', 'default', $connection_info['default']);
        Database::closeConnection('default', 'default');
        Database::getConnection('default', 'default');
    }

}