public function testGet()
{
$app = $this->getApp();
$filesystem = new Filesystem(new Local(PHPUNIT_ROOT . '/resources/'));
$app['filesystem']->mountFilesystem('config', $filesystem);
$command = new ConfigGet($app);
$tester = new CommandTester($command);
$tester->execute(['key' => 'sitename', '--file' => 'config.yml']);
$this->assertEquals("sitename: A sample site\n", $tester->getDisplay());
// test invalid
$tester = new CommandTester($command);
$tester->execute(['key' => 'nonexistent', '--file' => 'config.yml']);
$this->assertEquals("The key 'nonexistent' was not found in config.yml.\n", $tester->getDisplay());
}