DbCommandBaseTester example

class DbCommandBaseTest extends KernelTestBase {

  /** * Tests specifying a database key. */
  public function testSpecifyDatabaseKey() {
    $command = new DbCommandBaseTester();
    $command_tester = new CommandTester($command);

    Database::addConnectionInfo('magic_db', 'default', Database::getConnectionInfo('default')['default']);

    $command_tester->execute([
      '--database' => 'magic_db',
    ]);
    $this->assertEquals('magic_db', $command->getDatabaseConnection($command_tester->getInput())->getKey(),
       'Special db key is returned');
  }