HABTM broken promise

[lukaszx0]

Quoting changelog (https://github.com/rails/rails/blob/master/activerecord/CHANGELOG.md) :

has_and_belongs_to_many is now transparently implemented in terms of has_many :through. Behaviour should remain the same, if not, it is a bug.

It looks like it's not. I wanted to fix issue in AMS yesterday and it turned out it was broken only on edge rails and problem was with HABTM. Here's AMS PR: rails-api/active_model_serializers#404

I'll post proper failing test case for rails & will try to fix this issue later today.

/cc @tenderlove

[lukaszx0]

Forgot to mention. It's broken on master.

[tenderlove]

Any progress on a test case?

[rafaelfranca]

@spastorino @strzalek we will need a test case on the Rails code base. 😉

[lukaszx0]

Yes of course, I can and I will provide that.

@tenderlove sorry for no update on this. Few hours after posting this issue my macbook air died. I'll have it back in 4-5 days with replaced ssd and then I will try to attack this issue if anybody won't fix it before.

[lukaszx0]

@tenderlove thanks a lot! 🤘

[tanelj]

Hi!

It seems that there are still some issues with HABTM.

In Rail 4.1.0.rc1 (and in current 4.1 master) HABTM does not respect validate: false:

has_and_belongs_to_many :languages, validate: false

Currently validation is always called for associated objects.

For example this code is calling validation (on: :create) for language object even when validate: false:

event = Event.new
event.languages << Language.first
event.valid?

Here is minitest about the issue: https://gist.github.com/tanelj/9517608

It works fine in Rails 4.0.3.

[tenderlove]

@tanelj nice, thanks for the test case!

[carlosantoniodasilva]

@tanelj this has been fixed on master bae7f1d and backported to 4.1, should be good to go. Thanks for the test case, was very helpful! ❤️