Rspec helper module that logs in a user and avails that user to scenarios

login_helper.rb

module LoginHelper
  def sign_in(user)
    @signed_in_user = user

    visit root_path
    fill_in "Username", with: user.username
    fill_in "Password", with: user.password

    click_on "Log in"
  end

  def signed_in_user
    @signed_in_user
  end

  RSpec.configure do |config|
    config.before(:each) do |example|
      user_type = example.metadata[:sign_in]
      next unless user_type

      user = FactoryGirl.create(:user, user_type)
      sign_in(user)
    end
  end
end

# usage
# feature "Logs in user", sign_in: :admin do
#   scenario "the user is signed in" do
#     expect(signed_in_user).to be_admin
#   end
# end