gistfile1.rb

$:.unshift './'
require 'calculator'

describe Calculator do
  describe :constructor do
    it 'should take many arguments' do
      args = [1, 2, 3, 4]
      Calculator.new(*args).values.should eq(args)
    end
  end
  
  describe :calculation do
    describe 'for values: 3, 2' do
      subject { Calculator.new(3, 2) }
      its(:sum)      { should equal(5) }
      its(:subtract) { should equal(1) }
    end

    describe 'for values: 3, 5, 8' do
      subject { Calculator.new(3, 5, 8) }
      its(:sum)      { should equal(16) }
      its(:subtract) { should equal(-10) }
    end
  end
end