public function testGitClean()
{
$git = $this->getWorkingCopy();
file_put_contents(self::WORKING_DIR . '/untracked.file', "untracked\n");
$result = $git->clean('-d', '-f');
$this->assertSame($git, $result);
$this->assertFileNotExists(self::WORKING_DIR . '/untracked.file');
}