book.rb

class Book
    attr_accessor :title, :author, :category
        def initialize title, author, category
            @title = title
            @author = author
            @category = category
        end
end

book_spec.rb

require 'spec_helper'
 
describe Book do
  before :each do
    @book = Book.new "Title", "Author", :category
  end

  describe "#new" do
    it "takes three parameters and returns a Book object" do
      @book.should be_an_instance_of Book
    end
  end

  describe "#title" do
    it "returns the correct title" do
      @book.title.should eql "Title"
    end
  end

  describe "#author" do
    it "returns the correct author" do
      @book.author.should eql "Author"
    end
  end

  describe "#category" do
    it "returns the correct category" do
      @book.category.should eql :category
    end
  end
  
end

library.rb

class Library
  attr_accessor :books

  def initialize(lib_file = false)
    @lib_file = lib_file
    @books = @lib_file ? YAML::load(File.read(@lib_file)) : []
  end

  def get_books_in_category category
    @books.select do |book|
      book.category == category
    end
  end

  def add_book book
    @books.push book
  end

  def get_book title
    @books.select do |book|
      book.title == title
    end.first
  end

  def save lib_file = false
    @lib_file = lib_file || @lib_file || "library.yml"
    File.open @lib_file, "w" do |f|
      f.write YAML::dump @books
    end
  end

end

library_spec.rb

require 'spec_helper'

describe "Library object" do 
  before :all do
    lib_obj = [
            Book.new("JavaScript: The Good Parts", "Douglas Crockford", :development),
            Book.new("Designing with Web Standards", "Jeffrey Zeldman", :design),
            Book.new("Don't Make me Think", "Steve Krug", :usability),
            Book.new("JavaScript Patterns", "Stoyan Stefanov", :development),
            Book.new("Responsive Web Design", "Ethan Marcotte", :design)
    ]
    File.open "books.yml", "w" do |f|
      f.write YAML::dump lib_obj
    end
  end

  before :each do
    @lib = Library.new "books.yml"
  end
  
  describe "#new" do
    context "with no parameters" do
      it "has no books" do
        lib = Library.new
        lib.should have(0).books
      end
    end

    context "with a yaml file parameter" do
      it "has five books" do
        @lib.should have(5).books
      end
    end
  end

  it "returns all the books in a given category" do
    @lib.get_books_in_category(:development).length.should == 2
  end

  it "accepts new books" do
    @lib.add_book(Book.new("Designing for the Web", "Mark Boulton", :design))
    @lib.get_book("Designing for the Web").should be_an_instance_of Book
  end

  it "saves the library" do
    books = @lib.books.map { |book| book.title }
    @lib.save
    lib2 = Library.new "books.yml"
    books2 = lib2.books.map { |book| book.title }
    books.should eql books2
  end


end

spec_helper.rb

require_relative '../library'
require_relative '../book'
 
require 'yaml'

# This file was generated by the `rspec --init` command. Conventionally, all
# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
# The generated `.rspec` file contains `--require spec_helper` which will cause
# this file to always be loaded, without a need to explicitly require it in any
# files.
#
# Given that it is always loaded, you are encouraged to keep this file as
# light-weight as possible. Requiring heavyweight dependencies from this file
# will add to the boot time of your test suite on EVERY test run, even for an
# individual file that may not need all of that loaded. Instead, consider making
# a separate helper file that requires the additional dependencies and performs
# the additional setup, and require it from the spec files that actually need
# it.
#
# The `.rspec` file also contains a few flags that are not defaults but that
# users commonly want.
#
# See http://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
RSpec.configure do |config|
  # rspec-expectations config goes here. You can use an alternate
  # assertion/expectation library such as wrong or the stdlib/minitest
  # assertions if you prefer.
  config.expect_with :rspec do |expectations|
    # This option will default to `true` in RSpec 4. It makes the `description`
    # and `failure_message` of custom matchers include text for helper methods
    # defined using `chain`, e.g.:
    #     be_bigger_than(2).and_smaller_than(4).description
    #     # => "be bigger than 2 and smaller than 4"
    # ...rather than:
    #     # => "be bigger than 2"
    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
  end

  # rspec-mocks config goes here. You can use an alternate test double
  # library (such as bogus or mocha) by changing the `mock_with` option here.
  config.mock_with :rspec do |mocks|
    # Prevents you from mocking or stubbing a method that does not exist on
    # a real object. This is generally recommended, and will default to
    # `true` in RSpec 4.
    mocks.verify_partial_doubles = true
  end

# The settings below are suggested to provide a good initial experience
# with RSpec, but feel free to customize to your heart's content.
=begin
  # These two settings work together to allow you to limit a spec run
  # to individual examples or groups you care about by tagging them with
  # `:focus` metadata. When nothing is tagged with `:focus`, all examples
  # get run.
  config.filter_run :focus
  config.run_all_when_everything_filtered = true

  # Limits the available syntax to the non-monkey patched syntax that is
  # recommended. For more details, see:
  #   - http://myronmars.to/n/dev-blog/2012/06/rspecs-new-expectation-syntax
  #   - http://teaisaweso.me/blog/2013/05/27/rspecs-new-message-expectation-syntax/
  #   - http://myronmars.to/n/dev-blog/2014/05/notable-changes-in-rspec-3#new__config_option_to_disable_rspeccore_monkey_patching
  config.disable_monkey_patching!

  # This setting enables warnings. It's recommended, but in some cases may
  # be too noisy due to issues in dependencies.
  config.warnings = true

  # Many RSpec users commonly either run the entire suite or an individual
  # file, and it's useful to allow more verbose output when running an
  # individual spec file.
  if config.files_to_run.one?
    # Use the documentation formatter for detailed output,
    # unless a formatter has already been configured
    # (e.g. via a command-line flag).
    config.default_formatter = 'doc'
  end

  # Print the 10 slowest examples and example groups at the
  # end of the spec run, to help surface which specs are running
  # particularly slow.
  config.profile_examples = 10

  # Run specs in random order to surface order dependencies. If you find an
  # order dependency and want to debug it, you can fix the order by providing
  # the seed, which is printed after each run.
  #     --seed 1234
  config.order = :random

  # Seed global randomization in this process using the `--seed` CLI option.
  # Setting this allows you to use `--seed` to deterministically reproduce
  # test failures related to randomization by passing the same `--seed` value
  # as the one that triggered the failure.
  Kernel.srand config.seed
=end
end

zombie.rb

class Zombie
  attr_accessor :name, :brains

  def initialize
    @name = 'Ash'
    @brains = 0
  end

  def hungry?
    true
  end
end

zombie_spec.rb

require "spec_helper"
require "zombie"

describe Zombie do
  it "is named Ash" do
    zombie = Zombie.new
    zombie.name.should == 'Ash'
  end

  xit "has no brains" do
    zombie = Zombie.new
    zombie.brains.should < 1
  end

  it "is hungry" do
    zombie = Zombie.new
    zombie.hungry?.should == true
    #zombie.should be_hungry
  end
end