Rails3 / Mongoid : many-to-many relation and delete operation - ruby-on-rails

Question

I have the following model :
class User
include Mongoid::Document
include Mongoid::Timestamps
has_and_belongs_to_many :challenged, class_name: "Event", inverse_of: "challengers"
def challenge!(event)
self.challenged << event
self.save!
end
def unchallenge!(event)
self.challenged.where(_id: event.id).destroy_all
self.save!
end
end
class Event
include Mongoid::Document
include Mongoid::Timestamps
has_and_belongs_to_many :challengers, class_name: "User", inverse_of: "challenged"
end
The challenge! method works fine, but the unchallenge! one does not.
If I test it with the following code :
require 'spec_helper'
describe User do
before(:each) do
#user = User.create!
#event = Event.create!
end
it "should unchallenge an event" do
#user.challenge!(#event)
#user.unchallenge!(#event)
#user.challenged.should_not include(#event)
end
end
The test fails ; so it seems that the delete operation did not work.
The application logs are :
MONGODB test_mongo_test['users'].insert([{"challenged_ids"=>[], "_id"=>BSON::ObjectId('4f2d13fdbd028603f7000001')}])
MONGODB test_mongo_test['system.namespaces'].find({})
MONGODB test_mongo_test['events'].insert([{"challenger_ids"=>[], "_id"=>BSON::ObjectId('4f2d13fdbd028603f7000002')}])
MONGODB test_mongo_test['events'].update({"_id"=>BSON::ObjectId('4f2d13fdbd028603f7000002')}, {"$addToSet"=>{"challenger_ids"=>{"$each"=>[BSON::ObjectId('4f2d13fdbd028603f7000001')]}}})
MONGODB test_mongo_test['users'].update({"_id"=>BSON::ObjectId('4f2d13fdbd028603f7000001')}, {"$pushAll"=>{"challenged_ids"=>[BSON::ObjectId('4f2d13fdbd028603f7000002')]}})
MONGODB test_mongo_test['$cmd'].find({"count"=>"events", "query"=>{"$and"=>[{:_id=>{"$in"=>[BSON::ObjectId('4f2d13fdbd028603f7000002')]}}, {:_id=>BSON::ObjectId('4f2d13fdbd028603f7000002')}]}, "fields"=>nil}).limit(-1)
MONGODB test_mongo_test['events'].remove({"$and"=>[{:_id=>{"$in"=>[BSON::ObjectId('4f2d13fdbd028603f7000002')]}}, {:_id=>BSON::ObjectId('4f2d13fdbd028603f7000002')}]})
MONGODB test_mongo_test['events'].find({:_id=>{"$in"=>[BSON::ObjectId('4f2d13fdbd028603f7000002')]}})
MONGODB test_mongo_test['events'].find({:_id=>{"$in"=>[BSON::ObjectId('4f2d13fdbd028603f7000002')]}})

Answer 1

Check your application log
If I'm right self.challenged returns Event criteria, not User criteria, so fix is:
self.challenged.where(_id: event.id).destroy_all
Upd:
I've written same test as you did( just different model names ):
# announcement_list.rb
def challenge!(announce)
self.announcements << announce
self.save!
end
def unchallenge!(announce)
self.announcements.where( _id: announce.id ).destroy_all
self.save!
end
#anouncement_list_spec.rb
context 'stackoverflow#9132596' do
let!( :announcement_list ) { Factory( :announcement_list ) }
let!( :announcement ) { Factory( :announcement ) }
it 'kick announcement out of list on unchallenge! method call' do
announcement_list.challenge!( announcement )
announcement_list.unchallenge!( announcement )
announcement_list.announcements.should_not include( announcement )
end
end
This way i get my tests failed. Then I change:
def unchallenge!(announce)
self.announcements.destroy_all( conditions: { _id: announce.id })
self.save!
end
Yap, little bit tricky, and definitely should be placed in mongoid tracker. Hope this will help you.