public function testSetFeatureData()
 {
     if (!method_exists('SearchEngine', 'delete')) {
         $this->markTestSkipped('SearchEngine::delete() is undefined. Probably not yet present in the tested MW version.');
     }
     $searchEngine = $this->getMockBuilder('SearchEngine')->disableOriginalConstructor()->getMock();
     $searchEngine->expects($this->once())->method('setFeatureData')->with($this->equalTo('Some feature name'), $this->equalTo('Some feature expression'));
     $search = new Search();
     $search->setFallbackSearchEngine($searchEngine);
     $search->setFeatureData('Some feature name', 'Some feature expression');
     $this->assertEquals('Some feature expression', $search->getFeatureData('Some feature name'));
     $this->assertNull($search->getFeatureData('Some non-existent feature name'));
 }