module ActiveModel::Lint::Tests

a BlogPost model might return "blog_posts/blog_post".
to_partial_path is used for looking up partials. For example,

calling this method returns a string. Fails otherwise.
Passes if the object's model responds to to_partial_path and if

def test_to_partial_path
  assert_respond_to model, :to_partial_path
  assert_kind_of String, model.to_partial_path
end