error

rails g spree:install
      create  config/initializers/spree.rb
      create  config/spree.yml
      remove  public/index.html
      append  public/robots.txt
      create  app/assets/javascripts/store
      create  app/assets/javascripts/admin
      create  app/assets/stylesheets/store
      create  app/assets/stylesheets/admin
      create  app/assets/images/store
      create  app/assets/images/admin
      create  app/assets/javascripts/store/all.js
      create  app/assets/javascripts/admin/all.js
      create  app/assets/stylesheets/store/all.css
      create  app/assets/stylesheets/admin/all.css
      create  app/overrides
      append  config/environment.rb
      append  db/seeds.rb
     copying  migrations
    creating  database
     running  migrations
     loading  seed data
        rake  db:seed 
loading fixture /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree-b622352e49bd/core/db/default/spree/countries.yml
loading fixture /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree-b622352e49bd/core/db/default/spree/roles.yml
loading fixture /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree-b622352e49bd/core/db/default/spree/states.yml
loading fixture /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree-b622352e49bd/core/db/default/spree/zone_members.yml
loading fixture /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree-b622352e49bd/core/db/default/spree/zones.yml
loading ruby /Users/johanbruning/.rbenv/versions/1.9.3-p125/lib/ruby/gems/1.9.1/bundler/gems/spree_auth_devise-a6cdb117a819/db/default/users.rb
rake aborted!
Association named 'spree_roles' was not found; perhaps you misspelled it?

Tasks: TOP => db:load_dir
(See full trace by running task with --trace)
     loading  sample data
      insert  config/routes.rb
**************************************************
We added the following line to your application's config/routes.rb file:
 
    mount Spree::Core::Engine, :at => '/'
**************************************************
Spree has been installed successfully. You're all ready to go!
 
Enjoy!
rails g spree:install  50.52s user 7.53s system 93% cpu 1:02.07 total

Gemfile

source 'https://rubygems.org'

gem 'rails', '3.2.8'

# Bundle edge Rails instead:
# gem 'rails', :git => 'git://github.com/rails/rails.git'

gem 'sqlite3'


# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails',   '~> 3.2.3'
  gem 'coffee-rails', '~> 3.2.1'

  # See https://github.com/sstephenson/execjs#readme for more supported runtimes
  # gem 'therubyracer', :platforms => :ruby

  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

# To use Jbuilder templates for JSON
# gem 'jbuilder'

# Use unicorn as the app server
# gem 'unicorn'

# Deploy with Capistrano
# gem 'capistrano'

# To use debugger
# gem 'debugger'
gem 'spree', :github => 'spree/spree', :branch => '1-2-stable'
#gem 'spree_i18n', :github => 'spree/spree_i18n'
gem 'spree_auth_devise', :github => 'JohanB/spree_auth_devise'

Steps

rails new reproduce # rails 3.2.8
bundle install # after adding to the gemfile 
rails g spree:install # shows error about spree_roles, possible unrelated issue
powder link && powder open # or equivalent
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