public function setUsesIgBinarySerializeIfAvailable()
{
$theString = 'Just some value';
$backend = $this->prepareDefaultBackend();
$backend->expects($this->once())->method('set')->with($this->equalTo('VariableCacheTest'), $this->equalTo(igbinary_serialize($theString)));
$cache = new VariableFrontend('VariableFrontend', $backend);
$cache->initializeObject();
$cache->set('VariableCacheTest', $theString);
}