private function assertZipContains(array $contents, $file)
{
$zip = new \ZipArchive();
$zip->open($file);
$actual = array();
for ($i = 0; $i < $zip->numFiles; $i++) {
$actual[$zip->getNameIndex($i)] = $zip->getFromIndex($i);
}
$zip->close();
$this->assertEquals($contents, $actual);
}