From: Felix Natter <felix.natter@...>
Date: 2008-02-11T03:04:59+09:00
Subject: Rails: Problem with has_and_belongs_to_many

hello,

I have an m:n relationsship (has_and_belongs_to_many) between the models
CoreUser and CoreGroup. So from some rails experience I thought I'd
be able to add a (user,group)-relation simply by doing
agroup.core_users << auser. 

Unfortunately the following test-case fails on the last assertion
(unless I include the line that is commented out):

  def test_add_remove
    someuser = CoreUser.create!(:username => 'test2s', ...)
    ag = CoreGroup.find_by_path("/Administrators")
    assert !ag.core_users.include?(someuser)
    assert !someuser.core_groups.include?(ag)

    ag.core_users << someuser
#    someuser.core_groups << ag
    assert ag.core_users.include?(someuser)
    assert someuser.core_groups.include?(ag)
  end

Shouldn't it work with the line being commented out (one direction)?

thanks,

-- 
Felix Natter