public function testSharedInstace()
 {
     $this->assertFalse(DocumentStore::hasSharedInstance());
     $sharedInstance = DocumentStore::getSharedInstance();
     $this->assertInstanceOf('\\Matryoshka\\Model\\Wrapper\\Mongo\\Criteria\\Isolated\\DocumentStore', $sharedInstance);
     $this->assertTrue(DocumentStore::hasSharedInstance());
     DocumentStore::resetSharedInstance();
     $this->assertFalse(DocumentStore::hasSharedInstance());
     $sharedInstance = clone $sharedInstance;
     DocumentStore::setSharedInstance($sharedInstance);
     $this->assertTrue(DocumentStore::hasSharedInstance());
     $this->assertSame($sharedInstance, DocumentStore::getSharedInstance());
 }