Faster tests with Should & FactoryGirl

gistfile1.rb

# Very contrived example of how using class variables to hold expensive models/associations
# can drastically speed up tests when using Shoulda and FactoryGirl.
#
#  One caveat is that your test cases are no longer truly isolated.  That is, if your
#  test case modifies one of the "cached" instances, subsequent test cases may be invalid.
#
#  You should only store models as class variables if:
#     1) Your test cases do not modify their data, and
#     2) The data contained in the cached models isn't vital to your test case.
class TaskTest < ActiveSupport::TestCase
  
  # NOTE: Previous versions of this gist had this chunk of code inside a `setup` block.  Don't do that.  Do this instead.
  # Models that are expensive to create (lots of associations, callbacks, etc)
  # and are not vital to the innards of the tests can be stored as class variables.
  # This prevents them being created before *every single test case*
  @@account ||= Factory(:account)
  @@user ||= Factory(:user, :account => @@account)
  @@project ||= Factory(:project, :account => @@account)
  
  setup do
    # If we weren't passing in @@project and @@user, these factories
    # would create the Project and User associations internally,
    # before every single test case.
    @new_task = Factory(:task, :project => @@project, :assigned_to => @@user)
    @completed_task = Factory(:task, :completed_at => Time.now, :project => @@project, :assigned_to => @@user)
  end
  
  context "A Task" do
  
    should "know if it's been completed" do
      assert !@new_task.completed?
      assert @completed_task.completed?
    end
    
    should "know that a completed task is not blocking it" do
      assert !@new_task.is_blocked_by(@completed_task)
    end
    
  end

end