Patterns

A draft list of useful Cucumber patterns:

• XPath Sections
  • Description: ability to scope an inspection or webrat step to a part of the html.
  • Motivation: when an element appears at multiple locations in an html page you want the ability to specify which one a step refers to
  • Examples:
    

    Then I should see "logout" in the account section

    
    

    When I follow "next" in the pagination section

  • Implementation:
    • Steps like

      When /^I follow "([^\"]*)" in the (.*)$/

    • A mapping of section names to xpaths that can be used for scoping
    • Webrat needs a patch to allow xpaths to be used
• Easy objects
  • Description: generic step to create objects in a rails app
  • Motivation: when writing cucumber for rails, you often want to create some objects and set their properties
  • Examples:

    • Given the following People exist:
      | name | date of birth |
      | john | 20 Jan 1980   |
      | mary | 10 days ago   |

  • Implementation:
    • Generic step that has a model name and a table as arguments
    • Factory used to create an object for each row with the properties defined in the table
    • Transforms that map the properties to the correct type
• Relative times
• Manual steps
  • Description: have a step that indicates an action that requires a human
  • Motivation: some things can not be automatically tested (JS UI, captcha) and we still want cucumber to describe how the app should behave
  • Examples:
    

    Then /^.* \(manual step\)$/ do
    end

    
    

    And I fill in the captcha correctly (manual step)

  • Implementation: define a step that matches anything and a unique string that denotes a manual step
• Debugger
  • Description: a step to go into the debugger
  • Motivation: because puts statements just don’t cut it
  • Implementation:
    

    When I go to the homepage
    And debugger

    
    

    Then /^debugger$/ do
      debugger
    end

    
    

    
    >: cucumber features/test.feature 
    Feature: Test for debugger
      Scenario: Opening a debugger # features/test.feature:2
        When I go to the homepage  # features/step_definitions/webrat_steps.rb:10
    [23, 32] in /myproject/vendor/plugins/cucumber/bin/../lib/cucumber/core_ext/instance_exec.rb
       23          Thread.critical = old_critical
       24        end
       25        begin
       26          ret = send(mname, *args)
       27        ensure
    => 28          InstanceExecHelper.module_eval{ remove_method(mname) } rescue nil
       29        end
       30        ret
       31      end
       32    end
    /myproject/vendor/plugins/cucumber/lib/cucumber/core_ext/instance_exec.rb:28
    InstanceExecHelper.module_eval{ remove_method(mname) } rescue nil
    (rdb:1) puts response.body.split("\n").select{ |l| l =~ /meta/}
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    nil
    (rdb:1)

• Using tags for managing development progress / continuous integration breakage
• Using tags for linking to feature tracking (lighthouse, pivotal tracker, trac, etc)