update_attributes without :tag_list key sets tag_list to []

[snitko]

I have a problem while updating the model that is taggable. If I call update_attributes, but without the :tag_list - then all tags are removed from this object. Example:

q = Question.create(title: "How do I create tags?", tag_list: "ruby, rails, programming")
q.tag_list #=> ["ruby", "rails", "programming"]
q.update_attributes(title: "How do I delete tags?")
q.tag_list #=> []

So wrong. If I don't touch :tag_list, it shouldn't delete all of the existing tags on this model.

[seuros]

What version are you using ? I can't replicate this with the 3.2.5!

[snitko]

3.2.3
I'll try 3.2.5 and will report. Thank you.

[seuros]

I added a test for it. Just to be sure that it won't break later.

[snitko]

Ok, I figured it out. The problem was validation. I had a validation that checked the number of tags in the tag_list. It didn't allow to save the model unless there were between 3 and 15 tags in this list.

Now, the problem is, that in between the time #update_attributes is called and before the model is actually saved, tag_list stays empty. Therefore, I can't really validate it properly because although the tag_list will eventually not change, at the time of validation it is empty and the validation fails.

In your test that you've added in response to my issue, you can clearly see that problem: you have to #reload the model. Obviously, this is impractical during the validation. Would you recommend any solution to that?

[seuros]

I added reload just to be sure that i'm testing the database data and not the in memory one.
The tests will pass even without the reload.

Can you write a test case ?

[snitko]

Ok, I wrote a test to specifically address the validation issue and it passed: snitko@2d1f238

Which makes me think there is indeed something wrong with my app. If you don't mind, I'll report back if I manage to write a test that fails. And anyway, thank you for making me do it and discovering the problem further.

[seuros]

Ne za chto.
Please let me updated.

[aldosolis]

Any solution to this yet? I got the same problem in the following context:

class User 
  belongs_to :login 
  ...
end

class Login
   # tags
    acts_as_ordered_taggable_on :udfs
end

user = User.find(1)
user.update_attributes(login_attributes: { id: user.login.id, udf_list: "a, b, c", first_name: "Aldo" })

problem: model.login.name is updated but model.logins.udf_list is not updated

Using version 4.0.0