person_spec.rb

require 'spec_helper'

describe Person do
  before(:each) { @person = Person.new(name: "John", description: "cool guy") }
  
  it { @person.should be_valid }
  it 'validates name' do
    @person.name = ''
    @person.should_not be_valid
  end
  
  it 'validates description' do
    @person.description = ''
    @person.should_not be_valid
  end
end