public function getCacheThrowsExceptionForNonExistingIdentifier()
{
$cache = $this->getMockBuilder(Cache\Frontend\AbstractFrontend::class)->disableOriginalConstructor()->getMock();
$cache->expects($this->atLeastOnce())->method('getIdentifier')->will($this->returnValue('someidentifier'));
$this->cacheManager->registerCache($cache);
$this->cacheManager->getCache('someidentifier');
$this->cacheManager->getCache('doesnotexist');
}