factory girl build_stubbed example

user_spec.rb

class User < ActveRecord::Base
  def full_name
    "#{ last_name } #{ first_name }"
  end
end

describe User do

  # in this case a real AR object needless
  # profit => speed up, more test isolation(test does not fail when database connection is broken)
  it "should return full_name like combine last_name && first_name" do
    user = build_stubbed(:user, :last_name => 'Doe', :first_name => 'John')
    user.full_name.should eql 'Doe John'
  end

end