ScopedAssociations

ScopedAssociations is able to create multiple has_to and has_many associations between two ActiveRecord models.

Scoped Association works on Rails4+

Add this line to your application's Gemfile:

gem 'scoped_associations'

If you need it on a Rails3.2 project (without .joins support), add this one:

gem 'scoped_association', '0.0.5'

And then execute:

$ bundle

Or install it yourself as:

$ gem install scoped_associations

Just add scoped: true to your relation macro:

class Post < ActiveRecord::Base
  has_one :primary_tag,
    as: :owner,
    class_name: "Tag",
    scoped: true

  has_many :primary_tags,
    as: :owner,
    class_name: "Tag",
    scoped: true
end

Install gems:

$ bundle
$ bundle exec appraisal

Launch tests:

bundle exec appraisal rake

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request