Confirm Alerts using Cucumber with Selenium

gistfile1.rb

# create the following step to confirm the next alert

When /^(?:|I )follow "([^"]*)" and I confirm the next alert$/ do |link|
  page.evaluate_script('window.confirm = function() { return true; }')
  When "I follow \"#{link}\""
end

gistfile2.feature

# you can use it like this

Scenario: Delete user account
  Given I am on the dashboard site
  When I follow "Edit user account"
  When I follow "Delete user account" and I confirm the next alert
  Then I should be signed out
  When I try to sign in as the user
  Then I should see a signin form error