public function testClearCache()
 {
     $connection = $this->getMockBuilder('\\SMW\\MediaWiki\\Database')->disableOriginalConstructor()->getMock();
     $connection->expects($this->once())->method('selectRow')->will($this->returnValue(false));
     $instance = new ByIdDataItemFinder($connection);
     $instance->saveToCache(42, 'Foo#0##');
     $instance->getDataItemForId(42);
     $instance->clear();
     $instance->getDataItemForId(42);
 }
 /**
  * Add or modify a cache entry. The key consists of the
  * parameters $title, $namespace, $interwiki, and $subobject. The
  * cached data is $id and $sortkey.
  *
  * @since 1.8
  * @param string $title
  * @param integer $namespace
  * @param string $interwiki
  * @param string $subobject
  * @param integer $id
  * @param string $sortkey
  */
 public function setCache($title, $namespace, $interwiki, $subobject, $id, $sortkey)
 {
     if (strpos($title, ' ') !== false) {
         throw new MWException("Somebody tried to use spaces in a cache title! ({$title})");
     }
     $hashKey = HashBuilder::createHashIdFromSegments($title, $namespace, $interwiki, $subobject);
     if ($namespace == SMW_NS_PROPERTY && $interwiki === '' && $subobject === '') {
         $this->checkPropertySizeLimit();
         $this->prop_ids[$title] = $id;
         $this->prop_sortkeys[$title] = $sortkey;
     } else {
         $this->checkRegularSizeLimit();
         $this->regular_ids[$hashKey] = $id;
         $this->regular_sortkeys[$hashKey] = $sortkey;
     }
     $this->byIdDataItemFinder->saveToCache($id, $hashKey);
     if ($interwiki == SMW_SQL3_SMWREDIIW) {
         // speed up detection of redirects when fetching IDs
         $this->setCache($title, $namespace, '', $subobject, 0, '');
     }
 }