public function setPassesStringToBackend()
{
$theString = 'Just some value';
$backend = $this->prepareDefaultBackend();
$backend->expects($this->once())->method('set')->with($this->equalTo('StringCacheTest'), $this->equalTo($theString));
$cache = new StringFrontend('StringFrontend', $backend);
$cache->set('StringCacheTest', $theString);
}