Imagine the following model:

class Post extends \Illuminate\Database\Eloquent\Model
{
	public function scopeOfUser($query, $userId)
	{
		return $query -> where ('user_id', '=', $userId) ; 
	}
}

How would you unit test this method? Of course I could mock the $query as following:

class PostTest extends TestCase
{
	public function testScopeOfUsers()
	{
		$query = \Mockery::mock();
		
		$query
			-> shouldReceive ('where')
			-> with ('user_id', '=', 149)
			-> andReturn (':)');

		$post = new App\Post();
		
		$return = $post -> scopeOfUser ($query, 149);
		
		$this -> assertSame (':)', $return);
	}
}

But that is not checking the result of running the scope method; it is locking inner workings of the scope method. Should the inner workings change, the test would break.