logbook.rb

require 'rubygems'
require 'active_support'

class Logbook
  
  def initialize
    @entries = {}
  end
  
  
  def add_entry(date, num)
    if @entries.has_key?(date)
      @entries[date] << num
    else
      @entries[date] = [num]
    end
  end
  
  def find(date)
    @entries[date]
  end
  
  def find_for_day(date)
    numbers = []
    @entries.each_key do |time|
      numbers += @entries[time] if time >= date and time < (date + 1.day)
    end
    numbers
  end
  
  def sorted
    
  end
  
end

logbook_spec.rb

require File.dirname(__FILE__) + "/../log_book"
require 'rubygems'
require 'active_support'

describe "Logbook" do
  
  before(:each) do
    @logbook = Logbook.new
  end
  
  it "can return entries for date" do
    curr_time = Time.now
    @logbook.add_entry(curr_time, 4)
    @logbook.find(curr_time).should eql([4])
  end
  
  it "can return multiple entries for same time" do
    curr_time = Time.now
    @logbook.add_entry(curr_time, 10)
    @logbook.add_entry(curr_time, 10)
    @logbook.find(curr_time).should eql([10,10])
  end
  
  it "can return multiple entries for same day" do
    @logbook.add_entry(Date.today, 5)
    @logbook.add_entry((Date.today + 2.hours), 6)
    @logbook.add_entry(Date.tomorrow, 7)
    @logbook.add_entry(Date.yesterday, 8)
    @logbook.find_for_day(Date.today).should eql([5,6])
  end
  
  it "can return entries in date order" do
    @logbook.add_entry(Date.today, 1)
    @logbook.add_entry(Date.today - 1.hour, 2)
    @logbook.add_entry(Date.today + 1.hour, 3)
    @logbook.sorted.should eql([2,1,3])
  end
  
end