snippet.rb

# Validations
validates_presence_of     :email, :unless => Proc.new { |user| user.email.blank? }
validates_presence_of     :username, :unless => :registered_with_email?


def registered_with_username?
  self.username.blank?
end


describe Account, "created" do
  describe "with username and password" do
    subject { Factory.build(:account, :email => nil) }
    it { should be_valid }
  end

  describe "with email and password" do
    subject { Factory.build(:account, :username => nil) }
    it { should be_valid }
  end
end