gistfile1.rb

require 'rspec'

class Node
  attr_accessor :next
  attr_reader :name

  def initialize(name)
    @name = name
  end

  def circular?(start = self, current = self.next)
    puts "\nCircular called with START = #{start} and CURRENT = #{current}"
    if current.nil?
      false
    elsif start == current
      true
    else
      # what does here?
    end
  end

  def to_s
    name
  end
end

describe Node do
  describe "#circular?" do
    before do
      @a = Node.new("Node A")
      @b = Node.new("Node B")
      @c = Node.new("Node C")
      @d = Node.new("Node D")
      @e = Node.new("Node E")

      @a.next = @b
      @b.next = @c
      @c.next = @d
      @d.next = @e
    end

    it "should return true if the list is circular" do
      @e.next = @a
      @a.should be_circular
    end

    it "should return false if the list is not circular" do
      @a.should_not be_circular
    end
  end
end