public function testIteratingSearchQueryIteratesFilters()
 {
     $this->assertEquals(0, $this->object->count());
     $this->object->setIndex(new TestIndex());
     $this->assertInstanceOf(FilterAttribute::class, $this->object->getFilter('bob'));
     $this->assertInstanceOf(FilterAttribute::class, $this->object->getFilter('age'));
     $this->assertInstanceOf(FilterAttribute::class, $this->object->getFilter('gender'));
     foreach ($this->object as $filter) {
         $this->assertInstanceOf(FilterAttribute::class, $filter);
     }
 }