Factory Girl steps for Cucumber with MongoMapper: what about associations?

Update:

I tried to propagate the fix to Plucky itself, in vain. So far, it's not fixed. Use this patch, if you experience problems migrating your project from ActiveRecord to MongoMapper or MongoMapper problems not properly working with queries, even though the article is about FactoryGirl associations (which might've been changed in FactoryGirl itself by now).

I also came across hidden issues with MongoMapper, such as a method not working, but the test is designed in a way to pass. If it's my decision, I will try MongoId next time.

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If you have an association (an Article belonging to a User) and you write something like that in Cucumber:

Given the following article exists:
 | title      | user                       |
 | My article | email: writer1@example.com |

then the Factory Girl steps will handle this association for you, creating both an Article and a User for your test if they are of the ActiveRecord class. But this will throw an exception with MongoMapper.

Digging into the Factory Girl steps code explains why. Factory Girl steps use User.find(:first, :conditions => attributes) but syntax such as find(:first...) doesn't exist for MongoMapper.

MongoMapper uses Plucky gem for all the find methods. I wrote the following monkey patch to account for the missing attributes:

/config/initializers/plucky_ext.rb
----------------------------------

Plucky::Query.class_eval do
alias_method :find_old, :find
def find_new(*args)
  options = args.extract_options!
  first = args.shift
  args.push(options)

  case first
     when :first
       first(*args)
     when :last
       last(*args)
     when :all
       all(*args)
     else
       args.unshift(first) unless first.nil?
       find_old(*args)
  end
end
alias_method :find, :find_new
end

Now the Factory Girl steps work with associations