Levy Carneiro

Here’s a quick tip on how to test those helpers such as ‘new_post_path’ and ‘home_path’. Also those formatted routes such as ‘formatted_posts_path’. And why is important to test those.

Here’s how I test route helper methods.

# spec/controllers/ideas_controller_spec.rb

describe IdeasController do
  describe "GET /ideas/new" do
    it "should have helper method new_idea_path" do
      get :new
      new_idea_path.should_not be_nil
      new_idea_path.should == '/ideas/new'
    end

    it "should have helper method formatted_new_idea_path" do
      get :new, :format => :json
      formatted_new_idea_path.should_not be_nil
      formatted_new_idea_path.should == '/ideas/new.json'
    end

    (...)
  end
end

And why it’s important to test those methods, since they’re already tested by Rails tests?

Rails 2.3 has removed all those formatted_xxx named routes. Turns out these routes ate up a lot of memory and served minimal purpose. Read article here.

So if you use something like formatted_new_user, and you need to upgrade the application to Rails 2.3, it would be broken without test coverage.

Here’s a tip for creating a generic Cucumber step, handling the Webrat visit method.

Imagine you have many Cucumber scenarios, and you have many steps like these:

  Given I am on the new task page
  Given I am on the new project page
  Given I am on the home page

This way you’d have to create mapping between these strings above, to real paths inside the application. You could use the method ‘path_to’, which is already provided with Cucumber, inside features/support/paths.rb. That could lead to something like this:

# features/support/paths.rb

def path_to(page_name)
  case page_name

  when /new task/i
    new_task_path
  when /tasks/i
    tasks_path

  when /new user/i
    new_user_path
  when /users/i
    users_path

  when /home/i
    root_path

  # and so forth...

  else
    raise "Can't find mapping from \"#{page_name}\" to a path."
  end
end

Or you could use something more generic and more maintanable.

So, let’s take advantage of the path helpers already provided by Rails such as new_task_page, tasks_path, home_path, and do this instead:

  Given I am on the new_task page
  Given I am on the new_project page
  Given I am on the home page

And add this to your create_task_steps.rb:

# features/step_definitions/create_task_steps.rb

Given /^I am on the (.+) page$/ do |page_name|
  eval("visit #{page_name}_path")
end

This way Webrat will visit the path: new_page_path, and you won’t have to maintain the paths.rb file.

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Title: The RSpec Book: Behaviour Driven Development with RSpec, Cucumber and Friends

350 pages, Apr 2009

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ISBN: 9781934356371

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On this presentation “How I Learned to Love Testing”, Gregg Polack talks about:

• Why would you test your code?
• When do you test your code?
• The path to developer enlightenment
• Test Driven Development (TDD)
• Behavior Driven Development (BDD)
• Where’d RSpec come from?

The original post here, and the link to download the entire presentation with better quality than Vimeo’s.