Accomodating rails' default javascript-driven "delete" link behavior in Cucumber.

auto confirm js popups in cucumber.feature

# web_steps.rb 
When /^I am going to confirm all js popups on this page$/ do
  # hackish, but not unreasonable.
  page.evaluate_script("window.alert = function(msg) { return true; }")
  page.evaluate_script("window.confirm = function(msg) { return true; }")
end

# some_feature.feature
# note that "I am going to confirm..." has to be called after arriving on 
# a page and before pressing links that use confirm (delete, in most cases)
@javascript
Scenario: Admin user should be able to delete an existing category
    Given I am an admin user with the login "admin" and the password "password"
    And  there is a active study
    And  a category exists with name: "Behavioral", category_type: "treatment"
    And  I login as "admin" authenticating with "password"
    When I follow "Categories" within "#treatment_lists_categories_link"
    And  I am going to confirm all js popups on this page
    And  I follow "Delete Behavioral"
    Then I should be on the admin categories page
    And  I should not see "Behavioral" within "#content_panel"