env.rb

...


Devise::OmniAuth.test_mode!

Before do
  Devise::OmniAuth.short_circuit_authorizers!
  Devise::OmniAuth.stub!(:facebook) do |b|
    b.post('/oauth/access_token') do
      [200, {}, { :access_token => 'facebook_access_token' }.to_json]
    end

    b.get('/me?access_token=facebook_access_token') do
      [
        200, {},
        {
          :id         => '1111111111',
          :link       => 'http://facebook.com/username',
          :email      => '[email protected]',
          :first_name => 'User',
          :last_name  => 'Name',
          :website    => 'http://relike.com/users/username'
        }.to_json
      ]
    end
  end
end

After do
  Devise::OmniAuth.unshort_circuit_authorizers!
  Devise::OmniAuth.reset_stubs!
end

...

Gemfile

...

gem 'devise',
    :git => 'https://github.com/plataformatec/devise.git',
    :branch => 'omniauth'

gem 'oa-oauth', :require => 'omniauth/oauth'

...

group :development, :test do
  ...
  gem 'cucumber-rails', '0.3.2'
  gem 'cucumber', '0.9.3'
  ...
end

login.feature

...

Scenario: New user click on "Login" and login into relike
  Given I am on the home page
   When I follow "Login"
   Then I should see "Successfully authorized from Facebook account."

...