first_cake_spec.rb

require 'rspec'

class FirstCake

  attr_reader :name

  def initialize(name)
    @name = name
  end

  def self.all_da_cakes
    ['New York Cheesecake', 'Birthday Cake', 'Black Forest Cake', 'Ice Cream Cake', 'Fruit Cake' ].map do |name|
      new(name)
    end
    end
  end

  describe 'first cake' do
    subject { FirstCake.all_da_cakes }

    context '.all_da_cakes' do
      specify 'returns all da cakes!' do

        cake_array = []
        subject.each do |cake|
          cake_array << cake.name
        end

        expect(cake_array).to include 'Birthday Cake'
      end
    end

    context  '.first' do
      specify 'returns the first object in the array' do
        expect(subject.first.name).to eql 'New York Cheesecake'
      end

      specify 'does not return the last object in the array' do
        expect(subject.first.name).to_not eql 'Fruit Cake'
      end

      specify 'returns nil if there is no element' do
        expect([].first).to eql nil
      end
    end

    context '.first(n)' do
      specify 'returns the first two objects in the array' do
      array = subject.first(2).map(&:name)
      expect(array).to eql ['New York Cheesecake', 'Birthday Cake']
    end

    specify 'returns the first three objects in the array' do
      array = subject.first(3).map(&:name)
      expect(array).to eql ['New York Cheesecake', 'Birthday Cake', 'Black Forest Cake']
    end

    specify 'does not return moar cake than is available' do
      array = subject.first(100).map(&:name)
      expect(array).to eql ['New York Cheesecake', 'Birthday Cake', 'Black Forest Cake', 'Ice Cream Cake', 'Fruit Cake' ]
    end
  end

end