Inheritance: extends PostWithMultipleSlugsAndHelperTrait
 /**
  * Test that primary slug is set to $model->slugKeyName when set.
  */
 public function testSlugKeyNameProperty()
 {
     $post = PostWithMultipleSlugsAndCustomSlugKey::create(['title' => 'A Post Title', 'subtitle' => 'A Post Subtitle']);
     $this->assertEquals('dummy', $post->getSlugKeyName());
     $this->assertEquals('a.post.subtitle', $post->dummy);
     $this->assertEquals('a.post.subtitle', $post->getSlugKey());
 }