active_record_association_spec.rb

require 'spec_helper'

describe "ActiveRecord" do
  describe "association" do
    it "should point to the same object" do
      user = create(:user)
      user.current_location.should == nil

      user.update_location(latitude: 11, longitude: 22)
      user.current_location.should_not == nil

      location = UserLocation.first

      location.id.should == user.current_location.id
      location.object_id.should == user.current_location.object_id #fails on this line
    end
  end
end

user.rb

class User < ActiveRecord::Base

  has_many :locations, :class_name => 'UserLocation', :order => 'created_at DESC'
  has_one :current_location, :class_name => 'UserLocation', :conditions => {:is_active => true}
  has_many :past_locations, :class_name =>  'UserLocation', :conditions => {:is_active => false}, :order => 'created_at DESC'

  def clear_location
    unless current_location.nil?
      current_location.is_active = false
      current_location.save
      reload
    end
  end

  def self.clear_all_locations
    UserLocation.where(:is_active =>  true).each do |user_location|
      user_location.user.clear_location
    end
  end

end

user_location.rb

class UserLocation < ActiveRecord::Base
  geocoded_by nil
  belongs_to :user
end